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Seagrass meadows commonly reside in shallow sheltered coastal environments which are typically safe havens for mooring boats. There is evidence from around the globe that the use of common swinging chain moorings leads to halos of bare sediment in otherwise productive seagrass. These halos reduce animal abundance and diversity and lead to a loss of the carbon stored within sediments. To protect and enhance seagrass ecosystem services, low-cost simple solutions are required that can solve the problems of boating-based disturbance. In the present novel study, we provide evidence that the simple replacement of mooring chains with rope can significantly reduce damage to sensitive benthic habitats such as seagrass. At three locations across a range of environmental conditions, we provide evidence that well-established moorings constructed from rope do not damage seagrass. Overall, there was a significant effect (F1,756 = 299.46, p < 0.001) of the mooring type and distance from the mooring base. This equates to a 44% increase in seagrass cover within areas around a rope mooring relative to a chain one. Most small boat mooring activity happens within the summer months, therefore large heavy-duty winter mooring systems are not required in many situations, opening opportunities for adapted systems that have a reduced environmental impact. The present study suggests that there is a ready-made, low-technology, low-cost solution already in existence for halting the widespread loss of seagrass from small boat mooring damage and allowing recovery and opportunity for restoration.

ispartof: EVOLUTIONARY BIOLOGY vol:49 issue:2 pages:221-238 status: published

The novelty of the present study is to address the durability of corroded anchors for prestressing CFRP laminates. Two types of steel anchors, clamp anchors and wedge anchors, were used to prestress CFRP laminates and then subjected to steel corrosion through a galvanostatic acceleration approach, which was followed by tensile tests. Compared to clamp anchors, wedge anchors showed a superior durability performance in terms of their prestress retention, anchor efficiency, and resistance to the slippage of the CFRP laminate. After accelerated corrosion for 144 h, the clamp anchor exhibited a prestress retention of 79.1% and an anchorage efficiency of 55%, and the percentages became 9.0% and 100% for the wedge anchor. The slippage rates of the clamp anchor and the wedge anchor were 0.036 mm/kN and 0.026 mm/kN, respectively. Therefore, the wedge anchor, which exhibited higher prestress tension and anchorage efficiency, performed better than the clamp anchor. The present work provides an apparatus for exploring the corrosion-induced durability of steel anchors and experimental evidence that helps refine the provision in the guidelines for addressing anchor durability.

International audience; Clustering is inherently a process of exploratory data analysis. It has attracted more attention recently because much real-world data consists of multiple representations or views. However, it becomes increasingly problematic when dealing with large and heterogeneous data. It is worth noting that several approaches have been developed to increase computational efficiency, although most of them have some drawbacks: (1) Most existing techniques consider equal or static weights to quantify importance across different views and samples, so common and complementary features cannot be used. (2) The clustering task is performed by arbitrary initialization without caring about the rich structure of the joint discrete representation, and thus poorly executed. In this paper, we propose a novel approach called “Auto-Weighted Binary Multi-View Clustering Via Deep Initialization” for large-scale multi-view clustering based on two main scenarios. First, we consider the distinction between different views based on the importance of samples, and therefore apply a dynamic learning strategy for the automatic weighting of views and samples. Second, in the context of initializing binary clustering, we develop a new CNN feature and use a low-dimensional binary embedding by exploiting the efficient capabilities of Fourier mapping. Moreover, our approach simultaneously learns a joint discrete representation and performs direct clustering using a constrained binary matrix factorization; the optimization problem is perfectly solved in a unified learning model. Experimental results conducted on several challenging datasets demonstrate the effectiveness and superiority of the proposed approach over state-of-the-art methods in terms of accuracy, normalized mutual information, and purity.

In the paper the numerical modelling of ensuring slope stability and their analysing with using of different numerical methods are presented. We have designed the cutting walls with earth nails and anchors securing for modelling of slope stability ensuring. The calculate and the mechanism of failure process of the reinforced slopes were studied using the different methods for slope stability. The nailing significantly increased the stability level for using Spencer method. The anchors increased the stability level for using Spencer method. Increasing the nail or anchors length improved the stability of the reinforced slopes. The reinforced slope exhibited a significant the stability level.

Live streaming of agricultural products can reduce farmer losses caused by unsalable agricultural products and increase the income of farmers. Live streaming can be especially effective for green product sales as it can increase viewer understanding of and interest in the production and attributes of green products. Using the stimulus, organization, and response theoretical framework, this paper explores the influence of agricultural products anchors’ characteristics on consumers’ purchasing behavior and the mediating effect of green consumption cognition. The data come from surveys distributed online to Chinese shoppers who had participated in an agricultural livestreaming event. A total of 691 valid responses were received. Anchor characteristics of influence, sales promotion, and interactive entertainment were found to positively impact consumers’ purchasing behavior. Green consumption cognition, composed of environmental problem perception and green consumption awareness, has a positive impact on purchasing intent. Furthermore, anchor characteristics of influence and sales promotion can positively influence consumers’ purchasing behavior indirectly through green consumption cognition.

The aim of this study was to develop a physical activity advisory system supporting the correct implementation of sport exercises using inertial sensors and machine learning algorithms. Specifically, three mobile sensors (tags), six stationary anchors and a system-controlling server (gateway) were employed for 15 scenarios of the series of subsequent activities, namely squats, pull-ups and dips. The proposed solution consists of two modules: an activity recognition module (ARM) and a repetition-counting module (RCM). The former is responsible for extracting the series of subsequent activities (so-called scenario), and the latter determines the number of repetitions of a given activity in a single series. Data used in this study contained 488 three defined sport activity occurrences. Data processing was conducted to enhance performance, including an overlapping and non-overlapping window, raw and normalized data, a convolutional neural network (CNN) with an additional post-processing block (PPB) and repetition counting. The developed system achieved satisfactory accuracy: CNN + PPB: non-overlapping window and raw data, 0.88; non-overlapping window and normalized data, 0.78; overlapping window and raw data, 0.92; overlapping window and normalized data, 0.87. For repetition counting, the achieved accuracies were 0.93 and 0.97 within an error of ±1 and ±2 repetitions, respectively. The archived results indicate that the proposed system could be a helpful tool to support the correct implementation of sport exercises and could be successfully implemented in further work in the form of web application detecting the user’s sport activity.

Seagrasses represent an essential part of the coastal environment and are hence the target of many coastal restoration projects. Artificial seagrass (ASG) mats may facilitate seagrass growth, making them a captivating option for restoration projects. However, little is known about the forces occurring on mats deployed in marine environments and especially on how these forces are transmitted to the anchoring points. Here, we present a study of prototype biodegradable coconut-mesh mats as base layer for ASG meadows and investigate the forces that occur at the anchors. We test the performance of three mesh types under wave forcing using two different anchor configurations without ASG and subsequently test ASG mats of one mesh type under wave forcing and a 4-anchor configuration to assess the effect of the ASG on anchor loading as a function of incident orbital velocities. We found that the mat composition plays a more important role than the number of anchors in anchor load reduction. The anchor forces were 2–4 times higher at front anchors compared to rear anchors, relative to wave propagation direction, and were also considerably higher in that direction compared to the opposite direction. With ASG, the forces increased compared to the highest measured forces without ASG. The forces on the anchors were almost fully dominated by the drag on the ASG based on material properties, ASG reconfiguration and flow conditions. We derive a relation between horizontal orbital velocities and expected forcing on the anchor based on ASG properties and the corresponding area of each anchor and discuss relevant criteria for the design of ASG mats. This should help to assess the loading on anchors deployed for restoration under specific site conditions and chosen materials. Copyright © 2022 Villanueva, Paul and Schlurmann.

En aquesta tesi s'aborda el repte de detectar i reconèixer múltiples matrícules de cotxe en una sola imatge. Primer de tot es fa una recerca d'articles previs i es miren opcions factibles per crear un model propi. A partir d'aquí es crea, s'entrena i es testeja el model en un escenari real. A partir dels resultats es conclourà o no la viabilitat del model. En esta tesis se aborda el reto de detectar y reconocer múltiples matrículas de coche en una sola imagen. Primero de todo se hace una búsqueda de artículos previos y se miran opciones factibles para crear un modelo propio. A partir de ahí se crea, entrena y testea el modelo en un escenario real. Con los resultados obtenidos se concluirá o no la viabilidad del modelo. This thesis addresses the challenge of detecting and recognizing multiple car license plates in a single image. First of all, a search of previous articles is made and feasible options are looked at to create a unique model. From here the model is created, trained and tested on a real scenario. Based on the results, it will be concluded whether or not the model is viable.

In recent years, ultra-high performance concrete (UHPC) has been introduced in the design of orthotropic steel decks (OSD) to reduce the risk of fatigue cracking. To investigate the fatigue behaviour and fatigue damage process of the orthotropic steel-UHPC composite bridge deck, a full- scale specimen was designed and tested under cyclic loading. Test results show that the fatigue resistance of orthotropic steel-UHPC composite bridge deck satisfies the requirements of the designed vehicle load up to 2 million cycles with no cracks occurred in this phase. Rib-to-crossbeam weld and U-rib butt-welded connection are the two most vulnerable details to crack in OSD under cyclic loading. The fatigue resistance of U-rib bolted connection was investigated, and it is concluded that it performs better than that of U-rib butt-welded connection. The short-headed studs fractured under excessive cyclic loading and 5 types of the fatigue failure modes are identified. And the UHPC layer above the crossbeam exhibited limited number of cracks with the maximum crack width less than 0.05mm at the end of the cyclic, much beyond the requirements.

International audience; In externally prestressed structures, anchors and deviators are used to connect tendons to the main structure. Those reinforced concrete blocks are exposed to large stress concentration and in many cases need 3D non-linear computation to be assessed properly, especially when they are beyond the standard framework. This local stress computation remains a great challenge for externally prestressed bridge design or large span girders design and is often poorly evaluated. This paper presents the results of a nonlinear 3D analysis of an anchor block belonging to an 80 meters long externally prestressed box girder. This analysis has been done for an actual engineering study (Roissy Charles de Gaulle Airport, Paris) to understand the concrete stress behaviour and cracking causes at the anchorage zone. Each reinforcing bar is modelled, plain concrete is described by the Rankine criterion, and finite elements are 10-nodes tetrahedrons. Then, a yield design computation is performed to assess the safety factor on the ultimate state loading. For the collapse load, an elastoplastic analysis is computed thanks to a static approach and a kinematic approach. This dual approach gives an error estimation in constitutive law. Eventually, stress flaws and rebars constrains are analysed in order to understand the general behaviour of the anchor. © 2022 IABSE Symposium Prague, 2022: Challenges for Existing and Oncoming Structures - Report. All rights reserved.

In this work, we elaborate on the concept of process authenticity, which intuitively corresponds to the validity of all process steps and their proper binding. It represents the most exciting forefront of distributed ledger technology research concerning the primary challenge of reliably connecting distributed ledger networks to the physical context it must operate. More in detail, the paper describes a novel methodological approach to ensure the authenticity of business processes through blockchain and several security mechanisms applied to the digital twins of the actual processes. We illustrate difficulties and opportunities deriving from implementing process authenticity in concrete case studies in which we were involved as software designers belonging to three critical application domains: document dematerialization, e-voting, and healthcare.

Learning Analytics (LA) refers to the use of students’ interaction data within educational environments for enhancing teaching and learning environments. To date, the major focus in LA has been on descriptive and predictive analytics. Nevertheless, prescriptive analytics is now seen as a future area of development. Prescriptive analytics is the next step towards increasing LA maturity, leading to proactive decision-making for improving students’ performance. This aims to provide data-driven suggestions to students who are at risk of non-completions or other sub-optimal outcomes. These suggestions are based on what-if modeling, which leverages machine learning to model what the minimal changes to the students’ behavioral and performance patterns would be required to realize a more desirable outcome. The results of the what-if modeling lead to precise suggestions that can be converted into evidence-based advice to students. All existing studies in the educational domain have, until now, predicted students’ performance and have not undertaken further steps that either explain the predictive decisions or explore the generation of prescriptive modeling. Our proposed method extends much of the work performed in this field to date. Firstly, we demonstrate the use of model explainability using anchors to provide reasons and reasoning behind predictive models to enable the transparency of predictive models. Secondly, we show how prescriptive analytics based on what-if counterfactuals can be used to automate student feedback through prescriptive analytics.

Challenges of weak economic growth, population decline, and labour shortages led many countries across the world to introduce immigration policy changes in order to attract foreign migrants. This paper focuses on Japan (Tokyo) and the UK (Birmingham, Edinburgh and Glasgow) given common concerns over long term demographic trends and the burgeoning lack of labour supply in particular sectors of the economy through use of foreign labour. The paper shifts the focus from efforts focused on attracting and selecting foreign labour to the retention of such individuals. Drawing on research with EU migrants in Japan and the UK, the paper highlights how staying may occur after a period of mobility, rather than only being of relevance to those who never left their home region. The paper develops a new conceptual framework, which helps to identify different dimensions that shape migrant staying as a temporal process. It is highlighted how staying is shaped incrementally and facilitated or undermined over time in relation to the reciprocal importance of diverse assets, anchors and the changing biographies of migrants and the places in which they live – as well as the relational aspects of migrants’ ‘linked lives’.

Currently, data generated by smart devices connected through the Internet is increasing relentlessly. An effective and efficient paradigm is needed to deal with the bulk amount of data produced by the Internet of Things (IoT). Deep learning and edge computing are the emerging technologies, which are used for efficient processing of huge amount of data with distinct accuracy. In this world of advanced information systems, one of the major issues is authentication. Several techniques have been employed to solve this problem. Face recognition is considered as one of the most reliable solutions. Usually, for face recognition, scale-invariant feature transforms (SIFT) and speeded up robust features (SURF) have been used by the research community. This paper proposes an algorithm for face detection and recognition based on convolution neural networks (CNN), which outperform the traditional techniques. In order to validate the efficiency of the proposed algorithm, a smart classroom for the student's attendance using face recognition has been proposed. The face recognition system is trained on publically available labeled faces in the wild (LFW) dataset. The system can detect approximately 35 faces and recognizes 30 out of them from the single image of 40 students. The proposed system achieved 97.9% accuracy on the testing data. Moreover, generated data by smart classrooms is computed and transmitted through an IoT-based architecture using edge computing. A comparative performance study shows that our architecture outperforms in terms of data latency and real-time response.

El proyecto está enfocado en realizar el diseño de los Elementos No Estructurales para una edificación de seis pisos en la ciudad de Bogotá, analizándola en una zona de amenaza sísmica alta y un perfil de suelo tipo E. Los elementos a diseñar serán los antepechos y los muros divisorios en cada uno de los niveles de la estructura, esto con el fin de evaluar el comportamiento de cada uno al momento de someterse a diferentes fuerzas sísmicas y solicitaciones. Además, comprende un software, el cual permitirá diseñar los Elementos No Estructurales previamente mencionados de manera automática, optimizando para cada uno de los niveles de la estructura la distancia entre los anclajes a la estructura y su respectivo acero de refuerzo. This project aims to design the Non-Structural Elements of a six-story building, located in Bogotá D.C. The study object lies in a high seismic risk and E-type soil profile zone. The specific objects to be designed are the parapets and the dividing walls for each of the stories. This will be done in order to evaluate their behavior under different seismic forces and physical stress. In order to achieve this goal, an Excel-Visual Basic software has been developed. This tool will allow previously mentioned Non-Structural Elements to be designed automatically. Furthermore, it calculates and optimizes the distance between the anchorages, the structure and its respective reinforcing steel, for each of the levels of the building. http://unidadinvestigacion.usta.edu.co Pregrado

The notion of anchor plays a major role in modern detection algorithms such as the Faster-RCNN [1] or the SSD detector [2]. Anchors relate the features of the last layers of the detector with bounding boxes containing objects in images. Despite their importance, the literature on object detection has not paid real attention to them. The motivation of this paper comes from the observations that (i) each anchor learns to classify and regress candidate objects independently (ii) insufficient examples are available for each anchor in case of small-scale datasets. This paper addresses these questions by proposing a novel hierarchical head for the SSD detector. The new design has the added advantage of no extra weights, as compared to the original design at inference time, while improving detectors performance for small size training sets. Improved performance on PASCAL-VOC and state-of-the-art performance on FlickrLogos-47 validate the method. We also show when the proposed design does not give additional performance gain over the original design.

Background: Over the past years, the role of the acetabular labrum in hip joint biomechanics and its relations with joint health has been of particular interest. There is a good clinical improvement of patients in whom the acetabular labrum is preserved during arthroscopic hip surgery. The purpose of this study is to report the results of arthroscopic repair of labral tears at a medium term follow up. Materials and methods: We performed a retrospective review of all cases that underwent hip arthroscopy at our Institution from January 2013 until December 2018. There were 24 patients, 13 males and 11 females, and their mean age at the time of surgery was 29, 42 years (range, 19 to 43 years). All patients were treated by the same surgeon with an extracapsular OUT-IN approach. Suture was performed using a non-absorbable suture anchor all-suture. Clinical assessment was performed at December 2019 using a modified Harris hip score (mHHS), hip outcomes score activities of daily living (HOS ADL), hip outcomes score activities of sport scale (HOS SS). All patients with acetabular labrum injury had femoro-acetabular impingement. Results: The mean overall values in the preoperative period were 67.21 ± 10.31 for mHHS, 70.04 ± 12.11 for HOS-ADL and 60.06 ± 14.58 for HOS –SS. The results obtained in the re-evaluations of patients in December 2019 with a mean follow-up of 38, 3 months (minimum 1 year) are on average 82.17 ± 11.36 for mHHS, 83.00 ± 12.80 for HOS-ADL and 76.09 ± 18.52 for HOS-SS. Conclusions: The progress of knowledge and the advancement of diagnostic and therapeutic skills has led to a greater awareness of the importance of treating acetabular labrum tears. Arthroscopic treatment with suture appear to be a good option for these patients and we had encouraging results in our center. (www.actabiomedica.it)

Ongoing developments in genome sequencing have caused a fundamental paradigm shift in the field in recent years. With ever lower sequencing costs, projects are no longer limited by available raw data, but rather by computational demands. The high complexity of eukaryotic genomes in concordance with increasing data sizes creates unique demands on methods to assemble full genomes. We describe a new approach to assemble genomes from a combination of low-coverage short and long reads. LazyB starts from a bipartite overlap graph between long reads and restrictively filtered short-read unitigs, which are then reduced to a long-read overlap graph G. Instead of the more conventional approach of removing tips, bubbles, and other local features, LazyB stepwisely extracts subgraphs whose global properties approach a disjoint union of paths. First, a consistently oriented subgraph is extracted, which in a second step is reduced to a directed acyclic graph. In the next step, properties of proper interval graphs are used to extract contigs as maximum weight paths. These are translated into genomic sequences only in the final step. A prototype implementation of LazyB, entirely written in python, not only yields significantly more accurate assemblies of the yeast and fruit fly genomes compared to state-of-the-art pipelines but also requires much less computational effort. Our findings demonstrate a new low-cost method that enables the assembly of even large genomes with low computational effort.

Modern society is dependent on offshore cables and consequently cable faults lead to major disruption and economic loss. The most effective way to protect offshore cables from anchor damage is to bury them in the seabed, but current guidance is ambiguous. This paper attempts to produce more rational design guidance for anchor penetration in sand based on centrifuge modelling, allowing suitable burial depths for cables to be calculated based on the more useful metrics of anchor or ship size. A miniature anchor was dragged through sand of different densities within a centrifuge with maximum anchor penetration being measured. The most significant factor that influences anchor penetration depth is the size of the anchor, investigated by completing centrifuge tests at different g-levels. A linear relationship was recorded between anchor size and penetration depth which was used to develop new guidelines for cable burial. The new chart is clear and easy to use, with the cable burial depths given in relation to anchor size, anchor mass and ship mass. Use of this chart will enable the safe and economic burial of cables, and lead to a decrease in the impact of anchor damage to offshore cables.

As offshore energy developments move towards deeper water, moored floating production facilities are increasingly preferred to fixed structures. Anchoring systems are therefore of great interest to engineers working on deep water developments. Suction embedded plate anchors (SEPLAs) are rapidly becoming a popular solution, possessing a more accurate and predictable installation process compared to traditional alternatives. In this paper, finite element analysis has been conducted to evaluate the ultimate pullout capacity of SEPLAs in a range of post-keying configurations. Previous numerical studies of anchor pullout capacity have generally treated the soil as an elastic-perfectly plastic medium. However, the mechanical behaviour of natural clays is affected by inter-particle bonding, or structure, which cannot be accounted for using simple elasto-plastic models. Here, an advanced constitutive model formulated within the kinematic hardening framework is used to accurately predict the degradation of structure as an anchor embedded in a natural soft clay deposit is loaded to its pullout capacity. In comparison with an idealised, non-softening clay, the degradation of clay structure due to plastic strains in the soil mass results in a lower pullout capacity factor, a quantity commonly used in design, and a more complex load–displacement relationship. It can be concluded that clay structure has an important effect on the pullout behaviour of plate anchors.

This Thesis examines the mechanical response of large objects -called intruders or anchors that are embedded into a granular packing and subjected to dynamic loadings. By using a numerical approach based on a discrete element method, the study focuses on a canonical test comprising a plate-shaped intruder, placed horizontally and being uplifted vertically. The research is articulated into three projects. The first project considers steady and quasi-static loading conditions, whereby the intruder is uplifted at a constant velocity. Its purpose is to validate the numerical method against previously established models for the maximum drag force, also known as uplift capacity. Incidentally, this project establishes to what extent it is possible to downscale/upscale the size of the intruder relative to the grain size. This result is important as most laboratory and numerical tests, starting from those presented in this study, are performed with object-to-grain size ratios much smaller than real applications. The second project considers the mobility response under cyclic loading, whereby the object is subjected to a cyclic uplift force. A series of numerical tests exploring a range of loading frequency and magnitude reveals the existence of three possible mobility responses. The object can either move up steadily, not move up at all or exhibit a creep trajectory. Furthermore, this study points out a phenomena of elasto-inertial resonance inducing a fluidisation of the packing even at low loading magnitudes. The third project considers loading patterns including some acceleration of the object. This reveals a new contribution to the drag force, which we named “inertial drag”. We show that this contribution results from gradual mobilisation and acceleration of grains in the packing above the object. We further find that achieving a complete grain mobilisation takes a finite period of time, controlled by the elasto-inertial stress propagation from the object to the free surface. These three projects highlight fundamental differences between the drag force in quasi-static loading and dynamic loading conditions. A number of analytical models, built from identified micro-mechanical processes, are proposed to rationalise these effects

Máster en Ingeniería de Caminos, Canales y Puertos

The presence of dark pigment spots associated with primary tentacles (or structures derived from them, i.e., rhopalioids) in Staurozoa was recently overlooked in a study on the evolution of cnidarian eyes (defined as a “region made of photoreceptor cells adjacent to pigment cells”, irrespective of image formation, i.e., including all photoreceptive organs). Review of old and recent literature on Staurozoa shows that dark pigment spots are present in virtually all species of Manania, as well as some species of Haliclystus, Stylocoronella, and probably Calvadosia. The known ultrastructure of ocelli seems to be compatible with light perception, but no immediate response to changes in light intensity have been observed in the behavior of staurozoans. Therefore, although further studies addressing photic behavior are required, we discuss an earlier hypothesis that the dark spots in some stauromedusae may be related to synchronous spawning, as well as the possible sensorial function of rhopalioids. Observations summarized here suggest a possible ninth independent origin of eyes in Cnidaria, within a lineage of benthic medusae. Alternatively, documented similarity across medusae of Cubozoa, Scyphozoa, and Staurozoa – with eyes being topologically associated with primary tentacles in each of these taxa – could indicate shared ancestry and a single origin of eyes in this clade known as Acraspeda. Information on Staurozoa, one of the least studied groups within Cnidaria, is often neglected in the literature, but correctly recognizing the characters of this class is crucial for understanding cnidarian evolution.

Bulgaria is a country with a relief of various elevations. This is a precondition for appearance of landslides of different types. The present study deals with stabilizing approaches for a landslide on the road between two towns in Bulgaria. The landslide covers 63 m of the main road connecting the Bulgarian Black Sea capital of Burgas and the border between Bulgaria and Turkey. This road, I-9, is a first-class road which coincides with European Road E87 and passes through Bulgarian territory from north to south. In the spring of the year 2010 two parallel cracks appeared in the road near the km 282+000 mark and the road sank 2,5 m. The terrain of the landslide is steep with an inclination of 36° - 42°. The geological survey shows back filling, slope washed gravels and weathered bedrock to a depth of 12 m. Bed rock of marls is found below this depth. The sliding surface is a polygonal line. Stability calculations are made and an uncompensated landslide load is determined. Different approaches are used for stabilizing of the landslide – piles, anchors, drainage ribs and retaining walls, geo grids as well as their combinations. The typical anchors construction was not possible to be used because of the steep terrain and joint work of two rows of piles was designed instead. The road has been restored and under exploitation.

WOS: 000367635900005, In this study, an experimental investigation was conducted on normal strength concrete to examine the pullout capacity variation of cast in place anchors with the embedded circular surrounding studs around the anchored rebar under monotonic loading. Keeping constant the compressive strength of concrete, diameter and embedment length of anchored rebar, influence of number of embedded studs and distance between the circular surrounding studs and anchored rebar were chosen as the experimental parameters. Studs were embedded circularly around the anchored rebar with 10 and 20 cm diameter and number of studs was 4, 6 and 8 in each layer. For control purpose, anchored rebar without embedded studs were also tested. Unconfined tension test was performed according to the guideline of European technical approval of metal anchors for use in plain concrete. Test results revealed that embedded studs increased the pullout capacity of cast in place anchored rebar, increasing the number of studs increased the pullout capacity gradually; however, there was no meaningful difference in the pullout capacity of anchored rebar with the increase of stud layer. (C) 2015 Elsevier Ltd. All rights reserved.

In this study, we analyzed the methods and technologies used for constructing earthworks and military engineering in the latter period before the industrial revolution in Poland. The research object, the Warsaw Citadel, is a source of knowledge about military heritage from the aspect of conservation and protection of specific engineering achievements, which were dictated by early Russian geopolitical doctrine. Within the framework of the ongoing project of material heritage protection and popularization of history, the fortress has been transformed into a modern museum building. The new symbolic message of architecture was redefined, leaving behind the gloomy dominance elements in the scenery of the nearby city. In this study, reception tests of ground anchors were used for analysis. They were treated as a tool to determine the heterogeneity of fortification of historical earthworks. In the presented calculation procedure, limitations in the availability of geotechnical tests were overcome. Geological terrain layout and embankment excavation technology significantly impacted their quality and reliability. Currently, the embankments are slashed with anchored retaining walls. Ground anchors were used at short distances and were tested according to the national standard procedures. The results of the load tests are based on the physical properties of the subsoil, the conditions of contact with the supporting elements of the anchors, and the material properties. The soil interaction with the anchors is described using a rheological model, the constants of which were obtained using a fractional derivative model. The spatial variability of the rheological model parameters is presented using theoretical semivariograms matching the empirical data. The semivariograms explain the spatial correlation of the tested constants of the rheological model of the substrate with the anchors. The results of non-destructive testing were influenced by factors such as time and consolidation processes. The obtained results allowed us to directly draw conclusions about the repetitiveness of embankment features and indirectly about the quality of their construction.

[EN] Headed studs are key components of structures which facilitate composite behavior between steel and concrete elements. In steel building structures, reinforced concrete infill walls surrounded by a stiff steel frame is a common example of a composite structure used to resist horizontal loads such as those produced by earthquakes or wind. To this end, these types of concrete walls need to be anchored to the steel frame with headed studs which must withstand shear and tensile forces (AISC 360). To properly design headed stud anchors in concrete walls, it is first necessary to understand their behavior when subjected to monotonic shear forces considering edge conditions and reinforcing details that may influence the stud strength. Few tests have examined headed studs subjected to monotonic shear with typical boundary effects in reinforced infill walls, so a new experimental study on 17 specimens explores the behavior of headed studs exposed to monotonic shear loading with group effects. The experiments showed that the strength of studs installed in infill walls with edge conditions is well predicted (average error in prediction is smaller than 10%) by ACI 318, AISC 360 and EC-4. However, when group effects of anchors are included in the analysis of infill walls, only the ACI 318 is able to predict the behavior., The present study was funded by the Universitat Politecnica de Valencia (UPV) and the Spanish Ministry of Economy and Competitiveness through the Project BIA2015-70651-R. The authors would like to express their gratitude to Debra Westall for revising the manuscript.

This protocol describes the measurement of greenhouse gas (GHG) emissions from paddy soils using the static closed chamber technique. This method is based on the diffusion theory. A known volume of air overlaying a defined soil area is enclosed within a parallelepiped cover (named "chamber"), for a defined period of time. During this enclosure period, gases (methane (CH4) and nitrous oxide (N2O)) move from soil pore air near their microbial source (i.e., methanogens, nitrifiers, denitrifiers) to the chamber headspace, following a natural concentration gradient. Fluxes are then estimated from chamber headspace concentration variations sampled at regular intervals throughout the enclosure and then analyzed with gas chromatography. Among the techniques available for GHG measurement, the static closed chamber method is suitable for plot experiments, as it does not require large homogenously treated soil areas. Furthermore, it is manageable with limited resources and can identify relationships among ecosystem properties, processes, and fluxes, especially when combined with GHG driving force measurements. Nevertheless, with respect to the micrometeorological method, it causes a minimal but still unavoidable soil disturbance, and allows a minor temporal resolution. Several phases are key to the method implementation: i) chamber design and deployment, ii) sample handling and analyses, and iii) flux estimation. Technique implementation success in paddy fields demands adjustments for field flooding during much of the cropping cycle, and for rice plant maintenance within the chamber headspace during measurements. Therefore, the additional elements to be considered with respect to the usual application of non-flooded agricultural soils consist of devices for: i) avoiding any unintended water disturbance that could overestimate fluxes, and ii) including rice plants within the chamber headspace to fully consider gases emitted through aerenchyma transportation.

Within a risky choice framework, we examine how multiple reference points and anchors regulate pay perception and turnover intentions in real organizational contexts with actual employees. We hypothesize that the salary range is psychologically demarcated by three reference points into four regions, the minimum requirement (MR), the status quo (SQ), and the goal (G). Three studies were conducted: Study 1 analyzed the relationship between turnover intention and the subjective likelihood of falling into each of four expected salary regions; Study 2 tested the mediating effect of pay satisfaction on salary reference point-dependent turnover intention; and Study 3 explored the anchoring effect of estimated peer salaries. The results show that turnover intention was higher in the region below MR or between SQ and G but lower in the region above G or between MR and SQ. That is, turnover intention can be high even in situations of salary raise, if the raise is below a salary goal (i.e., leaving for a lack of opportunity) and low even in situations of salary loss, if the expected salary is still above the MR (i.e., staying for security). In addition, turnover intention was regulated by pay satisfaction and peer salaries. In conclusion, turnover intention can be viewed as a risky choice adapted to salary reference points.

У дисертацији је разматран проблем носивости анкера на чупањеи смицање у бетону веома високих чврстоћа. Издвојена су трипараметра који имају значајан утицај на носивост анкера.Реализовано је обимно експериментално истраживање, које јеконципирано тако да се даље може користити у нумеричкиманализама. Закључци су изведени на основу нумеричке анализе идефинисања утицаја варираних параметара помоћу неуронскихмрежа и факторијалног експеримента., U disertaciji je razmatran problem nosivosti ankera na čupanjei smicanje u betonu veoma visokih čvrstoća. Izdvojena su triparametra koji imaju značajan uticaj na nosivost ankera.Realizovano je obimno eksperimentalno istraživanje, koje jekoncipirano tako da se dalje može koristiti u numeričkimanalizama. Zaključci su izvedeni na osnovu numeričke analize idefinisanja uticaja variranih parametara pomoću neuronskihmreža i faktorijalnog eksperimenta., The dissertation discusses the problem of load anchors topulling out and shearing in ultra high strength concrete. Allocatethree parameters that have a significant impact on the loadcapacity of anchors. Realized an extensive experimentalresearch, which is designed so that could be used in numericalanalysis. Conclusions are drawn on the basis of a numericalanalysis, and defining the influence of varying the parametersusing the neural network and the factorial experiment.

In this paper we discussed a method to carry out a roughness inspection on the surface of fuel injection nozzle of ship engines. The nozzles are manufactured using hot isostatic pressing (HIP) technology. Microscopic blowholes are likely to be created during the process of manufacturing the nozzles, which causes the roughness on the surface even after fine machining. The objective of this research is to develop a technique to detect these microscopic blowholes. Digital image processing and a computational system are used to measure the roughness level. Length and breadth of the blowhole is measured using edge detection technique associated with a Gaussian filter and then edge drawing algorithm is used to draw fine edges along the detected edges. Based on the difference of intensity gradient along x-and y-direction, the edges of the blowholes are drawn. These detected edges are used to measure the size of blowhole.

The absence of appropriate structural connections is known to be one of the main factors contributing to the activation of out-of-plane mechanisms of masonry walls that can compromise the entire stability of a building. The high vulnerability of historical unreinforced masonry buildings to these types of mechanisms imposes the necessity to develop engineered strengthening solutions capable of ensuring positivewall-diaphragm anchorage to work in tension.A design methodology was developed covering aspects related to the estimation of the seismic demand and the design of a retrofit solution studied experimentally. The procedure proposed relies on the assessment of the resistant capacity associated with several possible failure modes and the estimation of the seismic demand considering the existing recommendations found on Eurocode 8 (CEN/TC 250 2010), ASCE/SEI 41-13, and NZSEE (2006)., The authors would like to acknowledge Professor Jason Ingham for providing essential information and technical expertise concerning the NZSEE (2006) application. This work was partially funded by project FP7-ENV-2009-1-244123-NIKER of the 7th Framework Program of the European Commission, and by FCT, within ISISE, project UID/ECI/04029/2013, which are gratefully acknowledged.

Background: Recent data suggest that inaccurate suture passage during remplissage may contribute to a loss of external rotation, with the potential to cause posterior shoulder pain because of the proximity to the musculotendinous junction. Purpose: To evaluate the accuracy of suture passage during remplissage and identify surface landmarks to improve accuracy. Study Design: Descriptive laboratory study. Methods: Arthroscopic remplissage was performed on 6 cadaveric shoulder specimens. Two single-loaded suture anchors were used for each remplissage. After suture passage, position was recorded in reference to the posterolateral acromion (PLA), with entry perpendicular to the humeral surface. After these measurements, the location of posterior cuff penetration was identified by careful surgical dissection. Results: Twenty-four sutures were passed in 6 specimens: 6 sutures (25.0%) were correctly passed through the infraspinatus tendon, 12 (50%) were through the infraspinatus muscle or musculotendinous junction (MTJ), and 6 (25%) were through the teres minor. Suture passage through the infraspinatus were on average 25 ± 5.4 mm inferior to the PLA, while sutures passing through the teres minor were on average 35.8 ± 5.7 mm inferior to the PLA. There was an odds ratio of 25 (95% CI, 2.1-298.3; P < .001) that the suture would be through the infraspinatus if the passes were less than 3 cm inferior to the PLA. Sutures passing through muscle and the MTJ were significantly more medial than those passing through tendon, measuring on average 8.1 ± 5.1 mm lateral to the PLA compared with 14.5 ± 5.5 mm ( P < .02). If suture passes were greater than 1 cm lateral to the PLA, it was significantly more likely to be in tendon ( P = .013). Conclusion: We found remplissage suture passage was inaccurate, with only 25% of sutures penetrating the infraspinatus tendon. Passing sutures 1 cm lateral and within 3 cm inferior of the PLA improves the odds of successful infraspinatus tenodesis. We recommend this “safe zone” to improve the odds of infraspinatus tenodesis during remplissage. These results may help improve remplissage techniques and prevent previously reported complications, including external rotation loss and pain from myodesis.

The uplift capacity of shallow horizontal strip anchors embedded in cohesionless soil has been obtained under seismic conditions. The limit equilibrium approach with log spiral failure surface together with modified pseudodynamic seismic forces has been adopted. In this modified pseudo dynamic approach, the soil is assumed to behave as a viscoelastic material overlying a rigid stratum and subjected to harmonic horizontal acceleration. This modified methodology satisfies the zero-stress boundary condition at the free ground surface. In the present methodology, the amplification of seismic acceleration depends on the soil properties and can be evaluated; hence, there is no need for assumption of any amplification value as is usually done in the literature. It is observed that the seismic acceleration distribution along the depth is highly nonlinear. The net seismic vertical uplift capacity factor for a unit weight component of soil (Fd) is estimated. The results under static and seismic conditions are determined for various combinations of input parameters, such as soil friction angle, embedment ratio, and seismic acceleration. It is observed that the design value of Fd decreases significantly with an increase in seismic acceleration. As expected, the seismic uplift capacity increases with an increase in embedment ratio and soil friction angle. Results in terms of nondimensional net seismic uplift capacity factor are presented in graphical form. In addition, the present results are compared and found to be in good agreement with a very few available similar results in literature. The present study reveals the lowest critical design values of seismic uplift capacity factor that may be used in seismic design of shallow strip anchors.

WOS:000370678700053 Here we present the first account of conductive polymer/colloidal nanoplatelet hybrids. For this, we developed DEH-PPV-based polymers with two different anchor groups (sulfide and amine) acting as surfactants for CdSe nanoplatelets, which are atomically flat semiconductor nanocrystals. Hybridization of the polymers with the nanoplatelets in the solution phase was observed to cause strong photoluminescence quenching in both materials. Through steady-state photoluminescence and excitation spectrum measurements, photoluminescence quenching was shown to result from dominant exciton dissociation through charge transfer at the polymer/nanoplatelet interfaces that possess a staggered (i.e., type II) band alignment. Importantly, we found out that sulfide-based anchors enable a stronger emission quenching than amine-based ones, suggesting that the sulfide anchors exhibit more efficient binding to the nanoplatelet surfaces. Also, shorter surfactants were found to be more effective for exciton dissociation as compared to the longer ones. In addition, we show that nanoplatelets are homogeneously distributed in the hybrid films owing to the functional polymers. These nanocomposites can be used as building blocks for hybrid optoelectronic devices, such as solar cells.

The signature is an important structural characteristic of a coherent system. Its computation, however, is often rather involved and complex. We analyze several cases where this complexity can be considerably reduced. These are the cases when a ‘large’ coherent system is obtained as a series, parallel, or recurrent structure built from ‘small’ modules with known signature. Corresponding formulae can be obtained in terms of cumulative notions of signatures. An algebraic closure property of families of homogeneous polynomials plays a substantial role in our derivations.

Generalized solutions for uplift capacity of inclined shallow strip anchors embedded in general c–ϕ soils with inclined slope carrying a uniform surcharge is developed in this paper for seismic condition. The individual effects of unit weight, surcharge and cohesion components on the computation of uplift capacity of anchors are considered. Limit equilibrium method with logspiral failure surface is adopted in the analysis and the effects of seismic forces are considered as pseudo-static forces. The results have been presented in the form of seismic uplift capacity factors as functions of anchor inclination, ground inclination, embedment ratio, soil friction angle and seismic acceleration coefficients both in the horizontal and vertical directions. Both the seismic accelerations change significantly the uplift capacity of anchors. Effect of the vertical seismic acceleration coefficient has been found to always reduce the uplift capacity whereas the effect of horizontal seismic acceleration coefficient has been found to reduce the uplift capacity in most of the cases. Results are presented in graphical and tabular forms. Estimation of error while using the principle of superposition to compute the seismic uplift capacity is also conducted. A comparative study between the present theory and available results in literature shows the merits and requirement of the present analysis.

The construction of reinforced concrete diaphragm walls under Encarnación Square comes after the demolition in 1972 of the antique “Mercado de Abastos”. Those works were included into the administrative concession of the Sevilla City Council for the constructions of a new market and underground parking. As the project annex, were made the calculation of the building’s diaphragm walls would contain 3 levels underground, with the conditioning factors to avoid damages on the buildings and roads around. The wall’s execution started on July and finished on November 2002. A total of 8835 m2 and 1840 m2 were built with 80 cm and 100 cm of thickness respectively. Once the containment structure was finished, the anchorages works begin between May and September 2003. This investigation exposes the calculation method used for the walls and anchors and shows the graphic of deformation obtained by inclinometers. La construcción de las pantallas en el solar de la plaza de la Encarnación, surge tras la demolición en 1972 del Antiguo Mercado de Abastos. Esta actuación estaba englobada dentro de la concesión administrativa que el Ayuntamiento de Sevilla adjudicó para la construcción de un nuevo Mercado y Aparcamiento Subterráneo. Como anejo del proyecto, se calcularon las pantallas que albergarían 3 niveles bajo rasante, con los condicionantes de minimizar la afección a los edificios y viales circundantes. Las pantallas se realizaron entre Julio y Noviembre de 2002. Se construyeron un total de 8.835 m2 y 1.840 m2 de pantalla de espesor 80 y 100 cm respectivamente. Con la estructura de contención ejecutada, comienzan a realizarse los anclajes provisionales entre mayo y septiembre de 2003. La investigación expone el método de cálculo utilizado para las pantallas y anclajes, los gráficos de deformación y la comprobación con lo realmente medido con los inclinómetros.

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2014, Thesis (M.Sc.) -- İstanbul Technical University, Instıtute of Science and Technology, 2014, Geoteknik mühendisliğinin en önemli inceleme alanlarından biri de derin kazı destekleme sistemleridir. Temel inşaatı sırasında güvenli bir çalışma ortamı sunabilmek ve çevre yapıları kazı esnasında oluşabilecek olan etkilerden koruyabilmek amacıyla derin kazı destek sistemleri kullanılmaktadır. Bu destekleme sistemleri kalıcı ya da geçici olarak inşa edilebilirler. Bu tez kapsamında, ülkemizde de oldukça yaygın olarak kullanılan öngermeli ankrajlı destek sistemleri üzerinde durulmuştur. Bu tezin konusu, önemli bir yapı kenarında gerçekleştirilen bir derin kazının desteklenmesi amacı ile inşa edilen bir iksa sisteminin araştırılması ve bazı parameterelerin iksa sisteminin davranışı üzerindeki etkilerinin araştırılmasıdır. İnşaat süresinin kısa olması sebebi ile inşa edilen iksa sistemi geçici özelliktedir. Bu tezde, Plaxis 8.2 sonlu elemanlar programı kullanılarak bir vaka analizi yapılmıştır. Bu çalışma kapsamında tarihi bir bina önünde oluşturulan iksalı kazı geoteknik mühendisliği uygulamalarında yaygın olarak kullanılan bir sonlu elemanlar programında modellenmiş ve çeşitli parametrelerin iksa sistemi üzerindeki etkileri araştırılmıştır. İlk bölümde derin kazı destekleme sistemlerinin önemine değinilmiş ve bu tezin kapsamı hakkında bilgi verilmiştir. Yanal toprak basınçları ikinci bölüm kapsamında detaylı bir şekilde incelenmiştir. Klasik toprak basıncı hesaplama metotlarına ek olarak destekli kazılarda ön tasarım hesapları için geliştirilen çeşitli toprak basıncı dağımlarına da detaylı olarak verilmiştir. Derin temel çukurlarını desteklemek amacıyla oluşturulan iksa sistemlerinin boyutlandırılması sisteme etkiyen bütün yüklerin belirlenmesi ve zemin cinsine ve destekleme sistemine en uygun görünür basınç diyagramının belirlenmesi ile gerçekleştirilir. Belirlenen toprak yükleri ile sisteme etkiyen sürşarj yüklerinin birlikte etkisi göz önünde bulundurularak iksa sistemi elemanlarına gelecek kesit tesirleri hesaplanır ve buna göre iksa elemanlarının boyutlandırılması yapılır. Üçüncü bölümde öngermeli ankrajlı duvarlar hakkında geniş bir literatür çalışmasına yer verilmiştir. Öngermeli ankrajlı iksa duvarını oluşturan yatay ve düşey destek elemanları, bu elemanların seçimi ve boyutlandırılması ve öngermeli ankrajlı duvarların imalat aşamaları, imalat süresince ankraj elemanlarının korunması ve uygulanan testler hakkında geniş kapsamlı bir literatür çalışması yapılmıştır. Öngermeli ankrajlarla oluşturulmuş bir iksa duvarında yenilme şekillerinin çoğu, elemanların yanlış boyutlandırılmaları sonucu meydana gelmektedir. Bu nedenle bu bölümde, ankraj elemanlarının boyutlandırılması hakkında standartlara atıfta bulunularak geniş yer verilmiştir. Derin kazılarda meydana gelebilecek deplasmanların sınırlandırılması amacıyla kullanılan öngermeli ankrajların tasarımında güvenli ankraj boyunun tayini oldukça önemlidir. Öngermeli ankrajlarda xxvi ankraj kök boyu ve serbest boyunun tayininde ankrajların boyutlandırılması potansiyel kayma düzleminin yeterli miktarda gerisinde kalacak şekilde yapılmalıdır. Bununla birlikte bu bölümde, öngermeli ankrajların kök boyunun belirlenmesinde zemin sürtünmesinin ve zeminin kohezyon durumunun da belirleyici olmasına değinilmiştir. Öngermeli ankrajlı bir iksa duvarının inşaası öncelikle toprak basıncı, sürşarj yükleri, yeraltı suyunun mevcut olduğu durumlarda hidrostatik basınç ve deprem kuvvetleri gibi duvara etkiyecek olan yanal kuvvetlerin belirlenmesi ile başlar. Genel olarak, geçici iksa sistemleri söz konusu olduğunda daha ekonomik bir tasarım açısından deprem kuvvetleri dikkate alınmamaktadır. Yine üçüncü bölüm kapsamında, öngermeli ankrajlı bir iksa duvarının oluşturulmasında kazı aşamaları ve ankrajların yerleştirilmesi sırasıyla verilmiştir. Temel çukurunun desteklenmesi için yapılmış olan bir derin kazı destek sisteminin, kazı çukuru açık kaldığı sürece dış etkilere maruz kalabileceği düşünülüp sistem elemanlarının korozyona karşı korunması önemlidir. Bu nedenle, öngermeli ankrajlı bir perde duvar elemanlarının korozyona uğramaması için alınacak önlemler üçüncü bölüm kapsamında yer bulmuştur. Bir derin kazı destekleme sisteminin özellikle de yakınlarında tünel, bina gibi önemli bir yapı bulunuyorsa büyük deformasyonlar yapmaması istenir ve tasarım buna göre yapılır. Derin kazı boyunca kazının her kademesinde deneyimli mühendislerce belirlenen zaman aralıklarında kazıda oluşan deformasyonların izlenmesi gerekmektedir. Böylece sistemin periyodik olarak gözlenmesi sağlanarak, kazı boyunca meydana gelebilecek herhangi bir sorunun önceden tespit edilip gerekli önlemlerin alınması sağlanır. Bu amaçla iksa duvarının arkasına deplasmanların izlenmesi için birtakım gözlem aletleri yerleştirilmelidir. Bu tez kapsamında incelenen alana ait yanal deplasman takibi inklinometre cihazlarıyla gerçekleştirilmiş olduğu için bu bölümde inklinometre gözlem aletlerinden bahsedilmiştir. İnklinometre kuyularının tesis edilmesi ve ölçüm alınması hakkında kısa bir bilgi verilmiştir. Öngermeli ankrajlı kazıklı duvar aktif bir iksa sistemi olup, her kademede oluşturulan ankrajlar belirlenen yüklerde yüklenerek sistem aktif hale getirilmektedir. Son olarak bu bölümde, öngermeli ankrajları aktif hale getirmek için uygulanan yükler ve testler ile de ilgili bilgiye yer verilmiştir. Öngermeli ankrajlı sistemlerde her bir ankrajın aldığı yük, yükleme deneyleri ile kanıtlanır. Diğer pek çok mühendislik probleminde olduğu gibi geoteknik mühendisliğinde de incelenen bir problemin daha basit ve anlaşılır bir hale getirilmesi için sonlu elemanlar ya da sonlu farklar metotlarından faydalanılmaktadır. Basit zemin yapıları için çoğunlukla bir boyutlu modeller yeterli olurken, çok tabakalı zemin profillerinin incelenmesi, istinat yapıları ve derin kazılar gibi daha karmaşık problemlerin çözülmesinde modelleme, iki veya üç boyutlu modelleme teknikleri kullanılarak gerçekleştirilmektedir. Bu tez çalışması kapsamında tarihi bir bina önünde gerçekleştirilen derin kazının modellenmesi Plaxis iki boyutlu sonlu elemanlar programı düzlemsel gerilme koşullarında kullanılarak gerçekleştirilmiştir. Bu nedenle dördüncü bölüm dahilinde, geoteknik mühendisliğinde sonlu elemanlar metodu ve modelleme tekniği hakkında bilgi verilmiştir. Daha sonra bu tez kapsamında yapılan çalışmalar boyunca kullanılan Plaxis 2 boyutlu sonlu elemanlar programı hakkında geniş bir bilgiye yer verilmiştir. Ayrıca tez kapsamında ele alınan vaka analizinin modellenmesinde kullanılan gelişmiş zemin modeli Hardening Soil Model hakkında da detaylı bilgi verilmiştir. Hardening Soil Model’de zemin rijitliği gerilme seviyesine bağlı olarak artan basınçla birlikte artmaktadır. Ayrıca bu modelde, zemini tanımlamak için programa girilen zemin mukavemet parametreleri ve elastisite modülü Mohr Coulomb Model’den farklı olarak derinlik boyunca artırılarak kullanılmaktadır. xxvii Önceki bölümlerde yapılan literatür çalışmalarının ardından, beşinci bölümde bir vaka analizine yer verilmiştir. Vaka analizi olarak Hilton İstanbul Bomonti Hotel ve Konferans Merkezi Projesi içinde yer alan tarihi bina önünde konumlandırılacak 7 katlı otoparkın temel inşaatı için yapılan destekli kazı sistemi ele alınmıştır. Bu tez kapsamında, başlıca tasarım ilkeleri ve ilgili standartlar göz önünde bulundurularak nümerik bir çalışma yapılmıştır. Bu bölüm kapsamında öncelikli olarak incelenen kesitin yer aldığı proje tanıtılmış, daha sonra proje için hazırlanmış geoteknik değerlendirme raporunda yer alan sondaj bilgileri, arazi ve laboratuvar deneyleri ile arazi için oluşturulan idealize zemin profiline yer verilmiştir. Geoteknik değerlendirme raporundan elde edilen bilgiler ışığında, yapılan ön tasarım çalışmaları sonucunda kazı destek sistemi olarak öngermeli ankrajlı mini kazıklı iksa duvarının uygun olduğuna karar verilmiş ve yatay toprak basıncına göre her bir ankraj noktasındaki kesit tesirleri hesaplanmıştır. Elde edilen maksimum kesit tesirlerine göre, sistemin ön boyutlandırılması yapılmıştır. Daha sonra, uygun iksa sistemi olarak kararlaştırılan derin kazı destekleme sistemin modeli, iki boyutlu Plaxis versiyon 8.2 sonlu elemanlar programında oluşturulmuştur. Tasarım parametreleri olarak geoteknik raporda önerilen idealize zemin profiline ait parametreler kullanılmış ve zemin modeli olarak da Hardening Soil Model seçilmiştir. Kazı süresince, inceleme konusu arazide her bir kazı kademesini takiben yerinde gözlemler ve aletsel okumalar yapılmıştır. Kazı süresince çevre ile etkileşimin iyi gözlenmesi ve düzenli olarak aletsel okumaların alınması sonucu, oluşabilecek problemler önceden tespit edilmiş ve projede revizyon yapılmasına karar verilmiştir. Revize edilmiş projenin modeli de Plaxis sonlu elemanlar programı versiyon 8.2 ile yapılmış olup sonuçlar beşinci bölümde verilmiştir. Daha sonra eski ve yeni projeler arasında birim fiyat tablosundan yararlanılarak bir maliyet karşılaştırılması yapılmıştır. Ayrıca bu bölümde, sonlu elemanlar programında girilen bazı parametrelerin iksa sistemi üzerindeki etkisi de araştırılmıştır. Bu amaçla, zemin mühendislik özelliklerinin, zemin/yapı arayüz elemanının ve yatay destek elemanları olarak kullanılan öngermeli ankrajların özelliklerinin iksa sisteminin rijitliği üzerindeki etkileri diğer parametrelerin sabit tutulması koşulu ile aynı geometri model üzerinde araştırılmıştır. İlk olarak zeminin elastisite modülü ve içsel sürtünme açısı değerleri değiştirilerek, Plaxis sonlu elemanlar programı ile geri analizler yapılmış ve elde edilen sonuçlara göre; bu mühendislik parametrelerinin iksa sisteminde meydana gelen deplasmanlar üzerindeki etkileri araştırılmıştır. Daha sonra arayüz azaltma faktörünün yanal yüke maruz kazık elemanındaki deplasmanlar üzerindeki etkisi Plaxis sonlu elemanlar programı kullanılarak araştırılmış; elde edilen sonuçlar sunularak arayüz elemanının kazığın yapıldığı malzeme ve zeminin cinsine göre karakteristik bir değer aldığı anlaşılmıştır. Son olarak ankraj kök boyunun, ankraj yerleştirme açısının, ankraj tendon çapının, ankraj yatay aralığının yanal deplasmanlar üzerindeki etkisi yine Plaxis sonlu elemanlar programı kullanılarak araştırılmış ve elde edilen sonuçlar grafikler ile sunulmuştur. Son bölümde, tez kapsamında yapılan çalışma özetlenmiş; ileriki çalışmalar için yararlanılması açısından sonuç ve önerilere yer verilmiştir. İksa sistemi tasarımında, sistemde oluşabilecek deplasmanların önceden tahmin edilmesinde sonlu elemanlar metodunun önemine değinilmiş ve kazı boyunca yapılan aletsel gözlemlerin tasarımın yeniden değerlendirilmesi ve gerektiği takdirde revize edilmesine olanak sağladığına değinilmiştir. Ayrıca derin kazıların modellenmesinde, zemin ve yapısal özelliklerin değişiminin sistemdeki etkileri de ileriki çalışmalara ışık tutması açısından neden-sonuç ilişkisi çerçevesinde verilmiştir., One of the most significant research subjects in geotechnical engineering is deep excavation support systems. Deep excavation support systems are used to provide a safety work area and to prevent the failure of surrounding structures during foundation construction. These excavation support systems can be built as permanent structures or temporary structures. Within the scope of this thesis, it is dwelled on prestressed anchored walls that are widely used also in our country. The subject of this thesis is the investigation of a shoring system that will be built to support a deep excavation near an adjacent structure and see the effect of some parameters on the behavior of the shoring system. The shoring system was built as a temporary system due to time of the construction. In this thesis, an actual case study was examined by using a finite element method program Plaxis 8.2. A prestressed anchored pile wall used as an excavation support system for the foundation construction of 7-storey car park as a part of Hilton Istanbul Bomonti Hotel and Conference Center. The depth of the excavation was 26 m and there was a historic building adjacent to excavation. Plaxis 8.2 software was used to model the behavior of the wall and the ground during the staged excavation. In the first chapter, a general information about the importance of deep excavation systems is given and the scope of the study is described. A detailed review of lateral earth pressures is presented in the second chapter. Different types of calculation methods for lateral earth presssures acting on braced cuts and anchored walls are given in detail in addition to classical lateral earth pressure calculation methods. In the third chapter, a detailed literature review of prestressed anchored wall is given. All elements forming a prestressed anchors are firstly represented. The determination criterias for sizing a prestressed anchored pile wall is given in detail according to the standards and codes. The failure mechanisms that may occur in prestressed anchored walls are also given in this chapter. The failure of a prestressed anchored wall may occur as a result of wrong sizing of the structural elements so that the sizing criterias are given in detail. The creation of a prestressed anchored pile wall starts with the determination of the lateral forces acting on the wall due to the lateral earth pressure, surcharge loads, water loads if ground water exists and earthquake loads. Mostly, earthquake loads are ignored while supporting the deep excavation with temporary systems to avoid unnecessary high costs. Moreover, the contruction stage and installation phases of a prestressed anchored pile wall is given step by step in chapter three. During a deep excavation, as long as the foundation works started, the deep excavation support elements must be protected to corrosion. The requirements for corrosion protection of prestressed ground anchors are also given in this chapter. It is xxiv wanted that a shoring system does not make large deformations especially if it is built near an important structure. Therefore, the shoring system must be observed until reaching the bottom of the deep excavation. For this purpose, some instruments were placed just behind the shoring wall to observe the lateral movements that will occur during the deep excavation. The investigated area given in this thesis was observed with inclinometers, thus a a detailed information about the inclinometers is given in this chapter as well. A prestressed anchored pile wall is an active retaining system which means that the ground anchors are loaded at the end of each construction stages. The anchor loading criterias are summarized at the end of chapter three. Finite element modelling in geotechnical engineering was elucidated in the fourth chapter. Moreover, it was given a detailed information about the finite element software Plaxis 2D in this chapter and also the Hardening Soil Model that was used to model the behavior of the ground in front of historic building is given. Following the literature research done in the previous sections, a case study is given in chapter five. In the case study, deep excavation for the foundation of 7-storey car park located in front of historic building included in Hilton Istanbul Bomonti Hotel and Conference Center is discussed. During this study, major design considerations are conceived. The deep excavation support system was selected as mini piled prestressed anchored wall according to the preliminary design and a numerical analysis was carried out by using finite element software Plaxis version 8.2. The idealized soil profile recommended in the geotechnical evaluation report was used in the design and the Hardening Soil Model was used for modeling. During the deep excavation, instrumental measurements and regular observations were carried out carefully and it was decided to the revise the shoring system project to prevent the occurance of some problems. The revised project was remodelled by Plaxis 8.2 and the outputs for the calculations were also given in this chapter. After that a cost analysis was done to compare the old and the revised projects. As well as in the fifth chapter, influence of some soil strength properties, structural properties and soilstructure interface properties were also investigated and the results were interpreted by graphs obtained from Plaxis calculations. First of all, back-calculations were carried out by changing the modulus of elasticity and the internal friction angle values and lateral displacements obtained for each model were given with graphs. After that for the same geometry model, back-calculations were done according to different interface reduction factor values and it was seen that the interface reduction factor is a characterictic property that takes different values according to the type of soil and structure. Also in this chapter, the effect of anchor bonded length, the inclination of the anchor with horizontal, the effect of nominal strand diameter and the horizontal spacing of ground anchors were investigated and the Plaxis results were given with graphs. In last chapter, the work carried out in the thesis was summarized with specific conclusions and recommendations for future studies were given as well., Yüksek Lisans, M.Sc.

The resistance of the anchors to the facade of collective protection (CP) or building aids (MAE) is an essential point of the stability of these elements, which in many cases is unknown. There have been numerous studies on resistance and behavior of the braces to concrete structures. But hardly any studies analyzing the strength of masonry anchors, much less masonry with decades of service in real situations: buildings that have to intervene and must anchor CP and MAE to its factories. In this study we have evaluated the pullout resistance of cancer plastic plugs inserted into staying in masonry building already built. The results were compared with those of other investigators and allowed to assess the requirements of the standard UNE-EN 12810-1 regarding the disposition and removal of scaffolding anchors to the facade. La resistencia de los anclajes a fachada de las protecciones colectivas (PC) o de los medios auxiliares de edificación (MAE) constituye un punto esencial de la estabilidad de esos elementos, que en muchos casos se desconoce. Se han realizado numerosos estudios acerca de la resistencia y del comportamiento de los anclajes metálicos a estructuras de hormigón. Sin embargo apenas existen trabajos que analicen la resistencia de anclajes a fábricas de albañilería y mucho menos a fábricas de albañilería con decenios de antigüedad en situaciones reales: edificios en los que hay que intervenir y es preciso anclar PC y MAE a sus fábricas. En este trabajo se ha evaluado la resistencia a arrancamiento de cáncamos insertados en tacos de plástico alojados en fábricas de albañilería de edificación ya construidas. Los resultados obtenidos se han comparado con los de otros investigadores y han permitido valorar las prescripciones de la norma UNE-EN 12810-1 relativas a la disposición y separación de anclajes de los andamios a fachada.

In the field of ocean engineering, a beginning has been made in the use of large-sized suction anchors for safe anchoring of large compliant structures. Suction anchors derive most of their uplift resistance from passive suction developed during the pullout movement. This article describes a set of laboratory tests on model suction anchors of three different embedment ratios to estimate the pullout behavior of suction anchors in soft clays typical of Indian marine clays. Tests were conducted on model anchors installed in soil beds prepared at four different consistencies in a test tank. This study shows the influence of soil consistency and embedment ratio (L/D) on the pullout behavior of suction anchors and on the variation of suction pressure at the top of the soil plug. The test results reveal that the behavior of suction anchors is much better than the behavior of open-ended anchors from the considerations of both capacity and deformation. The consistent development of suction inside the anchor top confirms the plug formation and significant breakout resistance in the form of suction-induced reversed end bearing. The results are further analyzed in terms of suction breakout factors. Further, the effect of burial depth of suction anchor on pullout behavior is shown.

Premature debonding of externally bonded FRP laminate from retrofitted reinforced concrete (RC) members can lead to inefficient use of FRP and can limit the level of strength increase that can be achieved. In this investigation, novel carbon FRP anchors were used in an attempt to delay the onset of premature debonding and to achieve superior strength. Nine double shear tests were performed on small scale concrete prisms to determine the most suitable epoxy for bonding the anchors to the laminate and the concrete. One type of epoxy increased the ultimate load of the prism retrofitted with two anchors at each end of the laminate 83.7% over the control specimens without anchors. The second phase of the investigation consisted of testing six large scale T-beams with a 4500 mm span, 400 mm height and 500 mm flange width under four point bending. Two beams were tested without FRP reinforcement as control beams, one beam was tested with FRP only epoxy bonded and the remaining three beams were tested with the FRP epoxy bonded and anchored. One of the beams with 30 anchors exhibited a 46% increase in the debonding load over the beam without anchors while the FRP laminate attained a maximum strain equal to 80% of its ultimate strain capacity, a 94% increase over the beam strengthened with only epoxy bonded FRP. The results demonstrate the anchoring system’s effectiveness and a feasible way to efficiently utilize the FRP laminate.

En la actual sociedad red, el uso de las tecnologías se han insertado en gran parte de las actividades sociales y la educación no ha quedado exenta de esta vinculación. El aporte de este artículo se enfoca en reflexionar como las narrativas digitales podrían posibilitar la configuración de didácticas de enseñanza que faciliten la transferencia del conocimiento y establecer estrategias de aprendizaje que permitan mejores desempeños en la asimilación y retención de los motivos educativos. // In today’s society network, using technologies have been inserted in many of the social activities and education has not been exempt from this link. The contribution of this article focuses on digital narratives reflect as may enable the configuration of didactic education to facilitate knowledge transfer and establish learning strategies that enable best performance in the assimilation and retention of educational reasons.

Economists have traditionally treated preferences as exogenously given. Preferences are assumed to be influenced by neither beliefs nor the constraints people face. As a consequence, changes in behaviour are explained exclusively in terms of changes in the set of feasible alternatives. Here the authors argue that the opposition to explaining behavioural changes in terms of preference changes is ill-founded, that the psychological properties of preferences render them susceptible to direct social influences, and that the impact of"society"on preferences is likely to have important economic and social consequences.

Two dimensional plane strain finite element analysis has been conducted to simulate the pullout behavior of vertical anchors of different shapes when embedded in clay. These shapes include plate anchors, anchors with irregular base shapes, and plate anchors with rectangular openings. For the first two types, the effects on the pullout behavior of embedment depth, overburden pressure, soil-anchor interface strength, anchor thickness, base shape and size, rate of clay strength increase, anchor and load inclination, point of load application and soil disturbance due to anchor installation were all studied. The anchor pullout capacity is shown to be strongly affected by embedment depth, overburden pressure, load inclination angle, rate of clay shear strength increase per depth and soil-anchor interface strength. Similarly, disturbed clay strengths adjacent to the anchor following installation were found to cause a significant reduction in the anchor capacity. The effect of other parameters, such as the anchor thickness and the load application point, were found to be less significant. Among the studied base shapes, the triangular based anchors were found to have the greatest vertical pullout resistance, while the lateral pullout was not significantly improved for any of the studied shapes. This form of anchor was also shown to be the most efficient shape in terms of cross-sectional steel area compared to the pullout capacity. Normal and inclined load vertical and horizontal plate anchors with rectangular openings were studied at different embedment depths for no-breakaway and immediate breakaway conditions. For this anchor type, the embedment depth showed a significant effect on the efficiency for fully bonded conditions, but only a negligible effect for immediate breakaway conditions. The results suggest the feasibility of this anchor type as an alternative to regular plate anchors, especially for shallow offshore conditions, where limitations on cranage capacity exist.

The construction of reinforced concrete diaphragm walls under Encarnación Square comes after the demolition in 1972 of the antique “Mercado de Abastos”. Those works were included into the administrative concession of the Sevilla City Council for the constructions of a new market and underground parking. As the project annex, were made the calculation of the building’s diaphragm walls would contain 3 levels underground, with the conditioning factors to avoid damages on the buildings and roads around. The wall’s execution started on July and finished on November 2002. A total of 8835 m2 and 1840 m2 were built with 80 cm and 100 cm of thickness respectively. Once the containment structure was finished, the anchorages works begin between May and September 2003. This investigation exposes the calculation method used for the walls and anchors and shows the graphic of deformation obtained by inclinometers., La construcción de las pantallas en el solar de la plaza de la Encarnación, surge tras la demolición en 1972 del Antiguo Mercado de Abastos. Esta actuación estaba englobada dentro de la concesión administrativa que el Ayuntamiento de Sevilla adjudicó para la construcción de un nuevo Mercado y Aparcamiento Subterráneo. Como anejo del proyecto, se calcularon las pantallas que albergarían 3 niveles bajo rasante, con los condicionantes de minimizar la afección a los edificios y viales circundantes. Las pantallas se realizaron entre Julio y Noviembre de 2002. Se construyeron un total de 8.835 m2 y 1.840 m2 de pantalla de espesor 80 y 100 cm respectivamente. Con la estructura de contención ejecutada, comienzan a realizarse los anclajes provisionales entre mayo y septiembre de 2003. La investigación expone el método de cálculo utilizado para las pantallas y anclajes, los gráficos de deformación y la comprobación con lo realmente medido con los inclinómetros.

BackgroundSecure tendon-to-bone fixation is essential for successful rotator cuff repair. Biomechanical properties of devices used in rotator cuff repair should be better understood.PurposeTo evaluate the response to incremental cyclic loading of 6 different anchor-suture complexes commonly used in rotator cuff repair.Study DesignControlled laboratory study.MethodsTwo absorbable anchors 5 mm and 6.5 mm in diameter and 1 metallic anchor, coupled with Ethibond or FiberWire, were tested on 5 pairs of fresh-frozen human cadaveric shoulders. An incremental cyclic load was applied until failure using a Zwich-Roell Z010 electromechanical testing machine. The ultimate failure load and mode of failure were recorded. An analysis of variance model was used for statistical analysis.ResultsThe FiberWire suture coupled with both absorbable and metallic anchors provided statistically significantly stronger fixation. However, although the metallic anchors in most cases failed because of slippage of the anchor, absorbable anchors failed because of rupture of the eyelet.ConclusionsThe FiberWire seems to increase the strength of fixation devices under cyclic load using both absorbable and metallic anchors, with relevant differences in failure mode (slippage of the metallic anchor and eyelet failure in the absorbable anchor).Clinical RelevanceUse of the FiberWire suture might change the mode of failure of the suture-anchor complexes.