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The pullout performance of various pedicle screws after artificial fusion process was investigated in this study. Normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws were tested. Polyurethane foams (Grade 10 and Grade 40) produced by casting method were used as test materials. The instrumentation of pedicle screws has been carried out with production of foams, simultaneously. For cemented pedicle screws, 3D models were prepared with respect to the anteriosuperior and oblique radiographs by using PMMA before casting procedure. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graph was recorded and the ultimate force was defined as the pullout strength sustained before failure of screw. As expected, the pullout strengths of pedicle screws in postfusion are higher than before fusion. Pullout strengths increased significantly by artificial fusion in Grade 10 foams compared to Grade 40 foams. Additionally, while the pullout strengths of normal, cannulated and novel expandable pedicle screws increased by artificial fusion, cemented normal pedicle screws had lower pullout values than before fusion in Grade 40 foams. When the cemented normal pedicle screws are excluded, other screws have almost similar pullout strength level. On the other hand, the pedicle screws have different increasing behaviour also, there is no correlation between each other. As a result, the novel expandable pedicle screws can be used instead of normal and cannulated ones due to their performances in non-cemented usage. © 2020, Acta Orthopædica Belgica., The authors would like to acknowledge to the Efmed (Efspine) Ltd. Sti. for donating the pedicle screws and PMMA.

The pullout performance of various pedicle screws after artificial fusion process was investigated in this study. Normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws were tested. Polyurethane foams (Grade 10 and Grade 40) produced by casting method were used as test materials. The instrumentation of pedicle screws has been carried out with production of foams, simultaneously. For cemented pedicle screws, 3D models were prepared with respect to the anteriosuperior and oblique radiographs by using PMMA before casting procedure. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graph was recorded and the ultimate force was defined as the pullout strength sustained before failure of screw. As expected, the pullout strengths of pedicle screws in postfusion are higher than before fusion. Pullout strengths increased significantly by artificial fusion in Grade 10 foams compared to Grade 40 foams. Additionally, while the pullout strengths of normal, cannulated and novel expandable pedicle screws increased by artificial fusion, cemented normal pedicle screws had lower pullout values than before fusion in Grade 40 foams. When the cemented normal pedicle screws are excluded, other screws have almost similar pullout strength level. On the other hand, the pedicle screws have different increasing behaviour also, there is no correlation between each other. As a result, the novel expandable pedicle screws can be used instead of normal and cannulated ones due to their performances in non-cemented usage. © 2020, Acta Orthopædica Belgica., The authors would like to acknowledge to the Efmed (Efspine) Ltd. Sti. for donating the pedicle screws and PMMA.

Since the Japanese Building Standards Act was revised in 2000, the installation of steel timber connectors (STCs) to reinforce timber frame (TF) connections has been mandated for new-build TF houses in Japan. However, for the TF houses built before then, more than 40% do not have sufficient STCs and are considered earthquake-prone. This study proposed a simple and easy seismic retrofit technique for such earthquake-prone existing houses. The proposed technique can reinforce TF connections using only plywood and common nails and achieve equivalent performance to the benchmark STCs used in Japanese TF houses, such as the CP-T type or the combination of VP type and BP type STCs. Experiments were performed to compare the proposed technique with the STCs using pullout and full-scale in-plane cyclic tests. The experimental results showed that the proposed technique had a higher seismic performance than the STCs, which was particularly excellent in displacement ductility to prevent a collapse of the TF house without damaging the timbers. The proposed technique will be accepted by many carpenters when retrofitting earthquake-prone existing houses because simple and easy.

Since the Japanese Building Standards Act was revised in 2000, the installation of steel timber connectors (STCs) to reinforce timber frame (TF) connections has been mandated for new-build TF houses in Japan. However, for the TF houses built before then, more than 40% do not have sufficient STCs and are considered earthquake-prone. This study proposed a simple and easy seismic retrofit technique for such earthquake-prone existing houses. The proposed technique can reinforce TF connections using only plywood and common nails and achieve equivalent performance to the benchmark STCs used in Japanese TF houses, such as the CP-T type or the combination of VP type and BP type STCs. Experiments were performed to compare the proposed technique with the STCs using pullout and full-scale in-plane cyclic tests. The experimental results showed that the proposed technique had a higher seismic performance than the STCs, which was particularly excellent in displacement ductility to prevent a collapse of the TF house without damaging the timbers. The proposed technique will be accepted by many carpenters when retrofitting earthquake-prone existing houses because simple and easy.

Since the Japanese Building Standards Act was revised in 2000, the installation of steel timber connectors (STCs) to reinforce timber frame (TF) connections has been mandated for new-build TF houses in Japan. However, for the TF houses built before then, more than 40% do not have sufficient STCs and are considered earthquake-prone. This study proposed a simple and easy seismic retrofit technique for such earthquake-prone existing houses. The proposed technique can reinforce TF connections using only plywood and common nails and achieve equivalent performance to the benchmark STCs used in Japanese TF houses, such as the CP-T type or the combination of VP type and BP type STCs. Experiments were performed to compare the proposed technique with the STCs using pullout and full-scale in-plane cyclic tests. The experimental results showed that the proposed technique had a higher seismic performance than the STCs, which was particularly excellent in displacement ductility to prevent a collapse of the TF house without damaging the timbers. The proposed technique will be accepted by many carpenters when retrofitting earthquake-prone existing houses because simple and easy.

Steel-strip reinforced earth walls stabilize through the pullout resistance of the reinforcements. Soil dilation during the pullout of ribbed reinforcements may contribute to the evolution of pullout resistance; however, few studies have clarified this mechanism by investigating how soils behave with increasing pullout displacement. The ribs of the reinforcements enhance the pullout resistance, although the influence of the rib dimensions on the evolution of pullout resistance with increasing pullout displacement has not been sufficiently revealed. In the present study, a triaxial pullout apparatus is developed and pullout tests are conducted using ribbed reinforcements with different rib-inclination angles under isotropic stress. The displacement and strain fields in the soils during the pullout of the reinforcements are investigated by X-ray micro CT and a digital image correlation technique. It is found that larger rib-inclination angles provide higher pullout resistance at an early stage of the pullout because of the higher bearing resistance related to the more significant soil densification above the ribs. With increasing pullout displacement, the reinforcements with different rib-inclination angles come to behave as almost one in the same since a rigid soil wedge related to the passive soil failure is generated above the ribs. This tendency results in similar soil deformation characteristics and pullout resistance levels for every reinforcement beyond the soil failure state, although the rib-inclination angles are different.

There are uncertainties related to the mechanical behaviour of highway embankments where frozen soil is used as fill material and experience natural thawing and settlements during the first thawing season following construction. Side slope sloughing, fill cracking, and development of localized thaw settlements underneath the embankment shoulders and side slopes typically occur due to thawing of the frozen soil and permafrost foundation. Test sections were constructed and instrumented with temperature and displacement sensors along the Inuvik-Tuktoyaktuk Highway in the Northwest Territories, Canada to assess the thermal and mechanical performance of frozen fill embankments. One of the test sections was reinforced with layers of wicking woven geotextiles at its side slopes to provide reinforcement against lateral movements and instabilities during the thawing season. This is the first research where woven geotextiles were used for slope reinforcement of initially frozen fill in Arctic regions. Significant lateral displacements occurred in the summer following end-of-construction for the control (unreinforced) and reinforced test sections, with the reinforced section showing reduced lateral movements. Temperatures in the embankment and permafrost foundation have also been increasing due to warming air temperatures, leading to additional displacements as the previously compacted frozen fill thaws. Large-scale direct shear and pullout tests were conducted on the soil and woven geotextiles, respectively, under different moisture contents and environmental conditions to quantify their influence on embankment performance. The most critical condition, based on the tests conducted, occurs during the onset of the first thawing when the ice bonding in the soil matrix melts. The interface properties obtained from the pullout tests showed that the wicking geotextile has higher interface friction properties compared to a non-wicking geotextile at comparable strain levels. Thermal

There are uncertainties related to the mechanical behaviour of highway embankments where frozen soil is used as fill material and experience natural thawing and settlements during the first thawing season following construction. Side slope sloughing, fill cracking, and development of localized thaw settlements underneath the embankment shoulders and side slopes typically occur due to thawing of the frozen soil and permafrost foundation. Test sections were constructed and instrumented with temperature and displacement sensors along the Inuvik-Tuktoyaktuk Highway in the Northwest Territories, Canada to assess the thermal and mechanical performance of frozen fill embankments. One of the test sections was reinforced with layers of wicking woven geotextiles at its side slopes to provide reinforcement against lateral movements and instabilities during the thawing season. This is the first research where woven geotextiles were used for slope reinforcement of initially frozen fill in Arctic regions. Significant lateral displacements occurred in the summer following end-of-construction for the control (unreinforced) and reinforced test sections, with the reinforced section showing reduced lateral movements. Temperatures in the embankment and permafrost foundation have also been increasing due to warming air temperatures, leading to additional displacements as the previously compacted frozen fill thaws. Large-scale direct shear and pullout tests were conducted on the soil and woven geotextiles, respectively, under different moisture contents and environmental conditions to quantify their influence on embankment performance. The most critical condition, based on the tests conducted, occurs during the onset of the first thawing when the ice bonding in the soil matrix melts. The interface properties obtained from the pullout tests showed that the wicking geotextile has higher interface friction properties compared to a non-wicking geotextile at comparable strain levels. Thermal

Aim of this study is to assess the pullout performance of various pedicle screws in different test materials. Polyurethane foams (Grade 10 and Grade 40) produced in laboratory and bovine vertebrae were instrumented with normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws. Test samples were prepared according to the ASTM F543 standard testing protocols and surgical guidelines. To examine the screw placement and cement distribution, anteriosuperior and oblique radiographs were taken from each sample after insertion process was completed. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graphs were recorded and the ultimate pullout force was defined as the maximum load (pullout strength) sustained before failure of screw. Student's t-test was performed on each group whether the differences between pullout strength of pedicle screws were significant or not. While normal pedicle screws have the lowest pullout strength in all test materials, normal pedicle screws cemented with polymethylmethacrylate exhibit significantly higher pullout performance than others. For all test materials, there is a significant improvement in pullout strength of normal screws by augmentation. While novel expandable pedicle screws with expandable poly-ether-ether-ketone shells exhibited lower pullout performance than normal screws cemented with polymethylmethacrylate, their pullout performances in all groups were higher than the ones of normal and cannulated pedicle screws. For all test materials, although cannulated pedicle screws exhibit higher pullout strength than normal pedicle screws, there are no significant differences between the two groups. The novel expandable pedicle screws with expandable poly-ether-ether-ketone shells may be used instead of normal and cannulated pedicle screws cemented with polymethylmethacrylate due to their good performances.

Aim of this study is to assess the pullout performance of various pedicle screws in different test materials. Polyurethane foams (Grade 10 and Grade 40) produced in laboratory and bovine vertebrae were instrumented with normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws. Test samples were prepared according to the ASTM F543 standard testing protocols and surgical guidelines. To examine the screw placement and cement distribution, anteriosuperior and oblique radiographs were taken from each sample after insertion process was completed. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graphs were recorded and the ultimate pullout force was defined as the maximum load (pullout strength) sustained before failure of screw. Student's t-test was performed on each group whether the differences between pullout strength of pedicle screws were significant or not. While normal pedicle screws have the lowest pullout strength in all test materials, normal pedicle screws cemented with polymethylmethacrylate exhibit significantly higher pullout performance than others. For all test materials, there is a significant improvement in pullout strength of normal screws by augmentation. While novel expandable pedicle screws with expandable poly-ether-ether-ketone shells exhibited lower pullout performance than normal screws cemented with polymethylmethacrylate, their pullout performances in all groups were higher than the ones of normal and cannulated pedicle screws. For all test materials, although cannulated pedicle screws exhibit higher pullout strength than normal pedicle screws, there are no significant differences between the two groups. The novel expandable pedicle screws with expandable poly-ether-ether-ketone shells may be used instead of normal and cannulated pedicle screws cemented with polymethylmethacrylate due to their good performances.

Installation of drilled-in epoxy-bonded reinforcing bars is generally an effective strengthening method to increase the flexural and shear capacities of deficient concrete structures. However, most of the available studies characterizing the bond behavior of epoxy bonded bars in concrete have been carried out on sound concrete elements—that is, without any pathological material damage. This raises the question of bond capacities in existing damaged elements. This study investigates the influence of alkali-silica reaction (ASR) on the capacity of post-installed reinforcing bars. ASR is a deleterious mechanism that causes expansion and cracking in the affected concrete elements. Pullout tests on post-installed reinforcing bars having embedded lengths of 2db, 4db, and 5db with 15M reinforcing bars (db = 15.9 mm [0.626 in.]) have demonstrated a drop-in bond strength when concrete is affected by ASR. In addition, the study revealed that the progression of concrete expansion due to ASR may lead to some confinement of the post-installed reinforcing bar and possibly increases the bond strength.

Steel reinforced ordinary Portland cement (OPC) concrete is a successful construction material due to its affordability, strength, and ease of construction. However, its success comes at a great risk to the environment because of the large carbon dioxide emissions associated with the cement production. Moreover, the steel bars, especially when the concrete is exposed to aggressive environments, are susceptible to corrosion. This high environmental footprint of reinforced concrete and its durability issues have inspired scientists and engineers to look for alternatives solutions. Glass fibre reinforced polymer (GFRP) bars, a corrosion resistant substitute to steel bars, and alkali activated cement (AAC) concrete, an environmentally friendly alternative to OPC concrete, stand out as ideal replacement materials. Different aspects of their individual properties have already been studied and their great potential has been reported. However, not much has been done on their bond properties. This research investigated the bond property between sand coated GFRP bars and fly ash based AAC concrete. The experimental program included pullout, beam-end, and beam splice tests. Bond stress-slip curves, factors affecting bond behaviour and tensile and bond stress distributions along the bar were studied.The results showed the comparable bond performance of AAC and OPC concretes with GFRP bars. A similar bond stress-slip behaviour was obtained for both AAC and OPC concretes in the sense that they display similar stages consisting of initial stiffening, nonlinear behaviour before peak stress, and softening when pullout failure takes place. The tensile and bond stress distributions along the embedment length were found to be nonlinear and the nonlinearity changes with the load. The experimental results were used to generate a constitutive bond stress-slip law. A good agreement was obtained between the numerical bond stress-slip curves and the experimental ones. Using the parameters of

This paper presents the 2D and 3D numerical analysis of pullout tests on steel anchorages in concrete blocks using standard and mixed finite elements. A novel (stabilized) mixed formulation in the variables of total strain 8 and displacements u is introduced to overcome the intrinsic deficiencies of the standard displacement-based one in the context of localization of strains, such as mesh dependency. The quasi brittle behavior of concrete is described through an elastoplastic constitutive law with a local Rankine yielding criterion. The proposed formulation is shown to be a reliable and accurate tool, sensitive to the physical parameters of the pullout tests, but objective with respect to the adopted FE mesh. Furthermore, the mixed epsilon/u finite element is able to capture the correct failure mechanism with relatively coarse discretizations. At the same time, the spurious behavior of the standard formulation is not alleviated by mesh-refinement., Peer Reviewed, Postprint (author's final draft)

Installation of drilled-in epoxy bonded reinforcing barsis generally an effective strengthening method for deficient concretestructures. However, this method of rehabilitation has largely been studied and tested on sound concrete elements, i.e. without any pathological damage, which raisesthe question of bond capabilities inexisting damaged elements. This investigation studies the influence of alkali-silica reaction (ASR) onthe capacity of epoxy bonded anchors. ASR, which is very common in eastern Canada, results from the chemical reaction between the alkali hydroxides in the concrete’s pore solution and some siliceous mineral phases inthe aggregates. Pull-out tests on epoxy bonded anchors havingembedded lengths offourtimes the bar diameter(Ø= 16 mm)have demonstrated a drop in bond strength when concrete is affected by ASR. In addition, the study revealed that the progression of concrete expansion due to ASR, leads to a confinement of the epoxy bonded anchor and increases the bond strength. These conclusions are therefore considered for the development of a model for the design of epoxy bonded anchors in existing concrete infrastructure affected by ASR.

The objective of this research was to develop and test high performance concrete mixtures, made of locally available materials, having durability characteristics that far exceed those of conventional concrete mixtures. Based on the results from the development of high performance concrete, guidelines for a high performance concrete bridge over Burnett Creek on SR 43, just north of I-65 near West Lafayette, Indiana, will be prepared. In addition, the effects of different curing conditions, with respect to temperature and moisture conditions, were evaluated. The use of 15.2 mm (0.6 in) prestressing strand in girders made of 69 MPa (10 ksi) concrete was also evaluated with respect to pullout resistance and transfer and development lengths.

Steel Fiber Reinforced Concrete (SFRC) allows overcoming brittleness and weakness in tension, the main drawbacks of plain concrete. The goal of the present presentation is to present an ad-hoc numerical strategy to account for the contribution of the fibers in the simulation of the mechanical response of SFRC. In the model presented, the individual fibers immersed in the concrete bulk are accounted for in their actual location and orientation. The selected approach is based on the ideas introduced in the Immersed Boundary (IB) methods. These methods were developed to account for 1D (or 2D) solids immersed in 2D (or 3D) fluids. Here, the concrete bulk is playing the role of the fluid and the cloud of steel fibers is acting as the immerse boundary (that is a 1D structure in a 2D or 3D continuous). Thus, the philosophy of the IB methodology is used to couple the behavior of the two systems, the concrete bulk and the fiber cloud, precluding the need of matching finite element meshes. In the proposed approach, the meshes of the concrete bulk and fiber cloud are independent and the models are coupled imposing displacement compatibility and equilibrium of the two systems. The concrete bulk is modeled using any nonlinear model. The constitutive model for the fibers is designed to account for the complex interaction between fibers and concrete. The fiber models are based on previous investigations describing the concrete-fiber interaction and its dependence on the factors identified to be relevant: shape of the fiber (straight or hooked) and angle between the fiber and the crack plane. 3D examples with fibers distributed and oriented randomly are reproduced using the proposed approach., Postprint (published version)

The objective of this research was to develop and test high performance concrete mixtures, made of locally available materials, having durability characteristics that far exceed those of conventional concrete mixtures. Based on the results from the development of high performance concrete, guidelines for a high performance concrete bridge over Burnett Creek on SR 43, just north of I-65 near West Lafayette, Indiana, will be prepared. In addition, the effects of different curing conditions, with respect to temperature and moisture conditions, were evaluated. The use of 15.2 mm (0.6 in) prestressing strand in girders made of 69 MPa (10 ksi) concrete was also evaluated with respect to pullout resistance and transfer and development lengths.

A large number of waste tires are generated each year throughout the world. Instead of disposing these tires in landfills, they can be used beneficially in road construction, MSE walls or structural fills that require large quantities of material. Such use of tires not only saves the costs of landfilling, but also provides certain desirable mechanical properties. The focus of this research was on determining important geotechnical properties of tire shred-sand mixtures required for their use as a lightweight backfill for MSE walls. Accordingly, the shear strength and pullout characteristics of tire shred-sand mixtures at various mixing ratios were determined through laboratory experiments. These properties are needed in the design of MSE walls with tire shred-sand mixtures as backfill material.

[EN] The positive effect of fibers on the bond of reinforcing bars in concrete is widely recognized. Different authors, however, come to different conclusions regarding particular points. This research analyzes the results of a series of pullout tests to obtain statistically supported conclusions regarding the bond performance of normal-strength steel fiber-reinforced concrete (SFRC). To do so, the experimental program was conceived by observing statistical criteria (design of experiments [DOE] technique), and the results were studied using the analysis of variance (ANOVA). It has been shown that the role fibers play in the bond of reinforcing bars in concrete is of the same importance as that of concrete cover or reinforcing bar diameter. It is especially remarkable that the mere fact of adding fibers¿regardless of the amount¿considerably increases the ductility of the bond failure, thus underlining the role of fibers in bond performance as passive confinement.

A large number of waste tires are generated each year throughout the world. Instead of disposing these tires in landfills, they can be used beneficially in road construction, MSE walls or structural fills that require large quantities of material. Such use of tires not only saves the costs of landfilling, but also provides certain desirable mechanical properties. The focus of this research was on determining important geotechnical properties of tire shred-sand mixtures required for their use as a lightweight backfill for MSE walls. Accordingly, the shear strength and pullout characteristics of tire shred-sand mixtures at various mixing ratios were determined through laboratory experiments. These properties are needed in the design of MSE walls with tire shred-sand mixtures as backfill material.

[EN] The positive effect of fibers on the bond of reinforcing bars in concrete is widely recognized. Different authors, however, come to different conclusions regarding particular points. This research analyzes the results of a series of pullout tests to obtain statistically supported conclusions regarding the bond performance of normal-strength steel fiber-reinforced concrete (SFRC). To do so, the experimental program was conceived by observing statistical criteria (design of experiments [DOE] technique), and the results were studied using the analysis of variance (ANOVA). It has been shown that the role fibers play in the bond of reinforcing bars in concrete is of the same importance as that of concrete cover or reinforcing bar diameter. It is especially remarkable that the mere fact of adding fibers¿regardless of the amount¿considerably increases the ductility of the bond failure, thus underlining the role of fibers in bond performance as passive confinement.

A large number of waste tires are generated each year throughout the world. Instead of disposing these tires in landfills, they can be used beneficially in road construction, MSE walls or structural fills that require large quantities of material. Such use of tires not only saves the costs of landfilling, but also provides certain desirable mechanical properties. The focus of this research was on determining important geotechnical properties of tire shred-sand mixtures required for their use as a lightweight backfill for MSE walls. Accordingly, the shear strength and pullout characteristics of tire shred-sand mixtures at various mixing ratios were determined through laboratory experiments. These properties are needed in the design of MSE walls with tire shred-sand mixtures as backfill material.

The use of fly ash in concrete has received significant attention over recent years due to environmental concerns regarding its disposal and on the other hand its potential use as a cementitious material, with its ability to provide significant benefits to concrete. While a fly ash content less than 25% of total cementitious content is routinely used in concrete, high-volume fly ash (HVFA) contents are not common used due to perceived lower early-age strengths. The objective of this research was to demonstrate that the beneficial effects of high in-place hydration might be able to compensate the slower rate strength gain of HVFA concrete that is typically observed when tested in standard laboratory conditions, in this effort, the maturity-based technique was used. In addition, different methods (match-cured cylinders and pullout testing) were used to estimate the early-age in-place strength of HVFA concrete to confirm the maturity predicted strengths. The results have shown that the standard and field-cured cylinder strengths underestimate the in-place concrete strength. Higher in-place temperatures due to the mass characteristics of structural elements resulted in increased early age in-place strengths, adequate for construction scheduling, as measured by match-cured cylinders,pullout testing, and the maturity approach. Furthermore, an extensive investigation on the use of the traditional and alternative maturity principles was examined in order to first identify it's applicability to these types of mixtures and, then identify potential adjustments to the maturity modeling as applicable to HVFA concrete mixtures. Two primary directions were followed, the constant and variable ultimate strength (Su) for multiple curing temperatures. Another objective of the study was to examine alternative methods of predicting activation energies (AE) for these cementitious systems, as compared to the traditional method identified by the maturity process. Among them, the setting ti

Cílem této bakalářské práce byla sumarizace dostupných informací o zemině vyztužené rozptýlenými vlákny. V minulosti bylo po celém světě provedeno velké množství studií zabývajících se tímto tématem. Práce srovnává přístup jednotlivých řešitelů k tomuto problému co se týče vlastností výztuže – její materiál, rozměry a podíl v zemině. Všechny tyto parametry se ukázaly velmi různorodé, zatímco některé zdroje hovoří o vláknech malých rozměrů, jiné naopak o velkých rozměrech. Nejčastěji používaným materiálem se ukázal polypropylen, ačkoliv nebyl zdaleka jediným. Lze hovořit o různých přírodních, syntetických a dokonce i odpadních, jinak nevyužitelných, materiálech. Podíl vláken v zemině je v dostupných pracích uváděn několika způsoby, zde jsou tyto způsoby zhodnoceny a porovnány. Na zemině vyztužené rozptýlenými vlákny je také nutné provádět laboratorní zkoušky pro zjištění vlivu výztuže na inženýrské chování zeminy. Tyto zkoušky se ovšem od zkoušení nevyztužených zemin v některých parametrech liší, proto je na rozdíly upozorněno. Dále jsou shrnuty přístupy konkrétních řešitelů k testování. Z prováděných laboratorních zkoušek lze uvést triaxiální smykovou zkoušku, smykovou krabicovou zkoušku a pro zeminu vyztuženou vlákny specifickou zkoušku vytržení výztuže. V závěru jsou uvedeny a zhodnoceny materiálové modely dostupné pro navrhování zeminy vyztužené vlákny., The goal of this thesis was the summarization of available information about Fiber-reinforced soil. In the past, many of the previous works were published around the world. This thesis compares what type of fibres are in previous studies used – especially material, their size and amount in the Fiber-reinforced soil. All of these parameters were quite various, some of the sources used small-sized fibres, some used large-sized fibres. The most common material was polypropylene, although it was not the only one. For example, natural fibres, other synthetic materials, and waste materials can be mentioned. The amount of the fibres in the soil is measured in a few different ways, so in this thesis are these ways compared. It is necessary to run laboratory tests to quantify the effect of the fibres on the mechanical engineering properties of the soil. These tests are quite different compared to tests run on the unreinforced soil, so these differences are mentioned. The ways, how Fiber-reinforced soil was tested in different studies, are compared. From laboratory tests can be mentioned triaxial shear test, direct shear test and for Fiber-reinforced soil typical pullout test. At the end of this thesis are said and compared material models available for Fiber-reinforced soil design.

Diplomová práce se zabývá statickou analýzou spojenou s výtokovým kanálem plavební komory. Podkladem pro práci byl návrh zesílení pomocí celozávitových předpínacích tyčí a výkresová dokumentace stávajícího stavu. Cílem práce bylo představení problematiky spojené s kotvením předpínacích tyčí soudržností ve stávající betonové konstrukci, zejména pak testování na zkušebních blocích v laboratoři pro ověření vhodného řešení. V návaznosti na získaná data provést analýzu a porovnání na modelech řešených nelineárním výpočtem v programu ATENA Science. Následně je provedena analýza modelu stávajícího stavu výseku výtokového kanálu rovněž nelineárním výpočtem s vyhodnocením jeho chování na extrémní zatížení. Tento model je následně doplněn o zesílení pomocí předpínacích tyčí s aplikací poznatků spojených s modely zkoušky vytržení. Model předepnutého výseku výtokového kanálu tak přestavuje simulaci provedení na samotné plavební komoře. Práce je doplněna o výkresy zkušebního bloku a zesílení výtokového kanálu., The thesis deals with the static analysis associated with the outlet channel of the lock chamber. The basis for the work was the design of reinforcement using full-threaded prestressing bars and the drawing documentation of the existing condition. The aim of the work was to present the issues associated with the anchoring of the prestressing bars by cohesion in the existing concrete structure, in particular testing on test blocks in the laboratory to verify a suitable solution. Following the data obtained, to perform an analysis and comparison on models solved by nonlinear computation in ATENA Science software. Subsequently, the analysis of the model of the existing condition of the outlet channel section is also carried out by nonlinear calculation with the evaluation of its behaviour to extreme loads. This model is then supplemented with reinforcement using prestressing bars with application of the knowledge associated with the pullout test models. The model of the pre-stressed outlet channel section is thus a simulation of the design on the lock itself.

Diplomová práce se zabývá statickou analýzou spojenou s výtokovým kanálem plavební komory. Podkladem pro práci byl návrh zesílení pomocí celozávitových předpínacích tyčí a výkresová dokumentace stávajícího stavu. Cílem práce bylo představení problematiky spojené s kotvením předpínacích tyčí soudržností ve stávající betonové konstrukci, zejména pak testování na zkušebních blocích v laboratoři pro ověření vhodného řešení. V návaznosti na získaná data provést analýzu a porovnání na modelech řešených nelineárním výpočtem v programu ATENA Science. Následně je provedena analýza modelu stávajícího stavu výseku výtokového kanálu rovněž nelineárním výpočtem s vyhodnocením jeho chování na extrémní zatížení. Tento model je následně doplněn o zesílení pomocí předpínacích tyčí s aplikací poznatků spojených s modely zkoušky vytržení. Model předepnutého výseku výtokového kanálu tak přestavuje simulaci provedení na samotné plavební komoře. Práce je doplněna o výkresy zkušebního bloku a zesílení výtokového kanálu., The thesis deals with the static analysis associated with the outlet channel of the lock chamber. The basis for the work was the design of reinforcement using full-threaded prestressing bars and the drawing documentation of the existing condition. The aim of the work was to present the issues associated with the anchoring of the prestressing bars by cohesion in the existing concrete structure, in particular testing on test blocks in the laboratory to verify a suitable solution. Following the data obtained, to perform an analysis and comparison on models solved by nonlinear computation in ATENA Science software. Subsequently, the analysis of the model of the existing condition of the outlet channel section is also carried out by nonlinear calculation with the evaluation of its behaviour to extreme loads. This model is then supplemented with reinforcement using prestressing bars with application of the knowledge associated with the pullout test models. The model of the pre-stressed outlet channel section is thus a simulation of the design on the lock itself.

Cílem této bakalářské práce byla sumarizace dostupných informací o zemině vyztužené rozptýlenými vlákny. V minulosti bylo po celém světě provedeno velké množství studií zabývajících se tímto tématem. Práce srovnává přístup jednotlivých řešitelů k tomuto problému co se týče vlastností výztuže – její materiál, rozměry a podíl v zemině. Všechny tyto parametry se ukázaly velmi různorodé, zatímco některé zdroje hovoří o vláknech malých rozměrů, jiné naopak o velkých rozměrech. Nejčastěji používaným materiálem se ukázal polypropylen, ačkoliv nebyl zdaleka jediným. Lze hovořit o různých přírodních, syntetických a dokonce i odpadních, jinak nevyužitelných, materiálech. Podíl vláken v zemině je v dostupných pracích uváděn několika způsoby, zde jsou tyto způsoby zhodnoceny a porovnány. Na zemině vyztužené rozptýlenými vlákny je také nutné provádět laboratorní zkoušky pro zjištění vlivu výztuže na inženýrské chování zeminy. Tyto zkoušky se ovšem od zkoušení nevyztužených zemin v některých parametrech liší, proto je na rozdíly upozorněno. Dále jsou shrnuty přístupy konkrétních řešitelů k testování. Z prováděných laboratorních zkoušek lze uvést triaxiální smykovou zkoušku, smykovou krabicovou zkoušku a pro zeminu vyztuženou vlákny specifickou zkoušku vytržení výztuže. V závěru jsou uvedeny a zhodnoceny materiálové modely dostupné pro navrhování zeminy vyztužené vlákny., The goal of this thesis was the summarization of available information about Fiber-reinforced soil. In the past, many of the previous works were published around the world. This thesis compares what type of fibres are in previous studies used – especially material, their size and amount in the Fiber-reinforced soil. All of these parameters were quite various, some of the sources used small-sized fibres, some used large-sized fibres. The most common material was polypropylene, although it was not the only one. For example, natural fibres, other synthetic materials, and waste materials can be mentioned. The amount of the fibres in the soil is measured in a few different ways, so in this thesis are these ways compared. It is necessary to run laboratory tests to quantify the effect of the fibres on the mechanical engineering properties of the soil. These tests are quite different compared to tests run on the unreinforced soil, so these differences are mentioned. The ways, how Fiber-reinforced soil was tested in different studies, are compared. From laboratory tests can be mentioned triaxial shear test, direct shear test and for Fiber-reinforced soil typical pullout test. At the end of this thesis are said and compared material models available for Fiber-reinforced soil design.

Cílem této bakalářské práce byla sumarizace dostupných informací o zemině vyztužené rozptýlenými vlákny. V minulosti bylo po celém světě provedeno velké množství studií zabývajících se tímto tématem. Práce srovnává přístup jednotlivých řešitelů k tomuto problému co se týče vlastností výztuže – její materiál, rozměry a podíl v zemině. Všechny tyto parametry se ukázaly velmi různorodé, zatímco některé zdroje hovoří o vláknech malých rozměrů, jiné naopak o velkých rozměrech. Nejčastěji používaným materiálem se ukázal polypropylen, ačkoliv nebyl zdaleka jediným. Lze hovořit o různých přírodních, syntetických a dokonce i odpadních, jinak nevyužitelných, materiálech. Podíl vláken v zemině je v dostupných pracích uváděn několika způsoby, zde jsou tyto způsoby zhodnoceny a porovnány. Na zemině vyztužené rozptýlenými vlákny je také nutné provádět laboratorní zkoušky pro zjištění vlivu výztuže na inženýrské chování zeminy. Tyto zkoušky se ovšem od zkoušení nevyztužených zemin v některých parametrech liší, proto je na rozdíly upozorněno. Dále jsou shrnuty přístupy konkrétních řešitelů k testování. Z prováděných laboratorních zkoušek lze uvést triaxiální smykovou zkoušku, smykovou krabicovou zkoušku a pro zeminu vyztuženou vlákny specifickou zkoušku vytržení výztuže. V závěru jsou uvedeny a zhodnoceny materiálové modely dostupné pro navrhování zeminy vyztužené vlákny., The goal of this thesis was the summarization of available information about Fiber-reinforced soil. In the past, many of the previous works were published around the world. This thesis compares what type of fibres are in previous studies used – especially material, their size and amount in the Fiber-reinforced soil. All of these parameters were quite various, some of the sources used small-sized fibres, some used large-sized fibres. The most common material was polypropylene, although it was not the only one. For example, natural fibres, other synthetic materials, and waste materials can be mentioned. The amount of the fibres in the soil is measured in a few different ways, so in this thesis are these ways compared. It is necessary to run laboratory tests to quantify the effect of the fibres on the mechanical engineering properties of the soil. These tests are quite different compared to tests run on the unreinforced soil, so these differences are mentioned. The ways, how Fiber-reinforced soil was tested in different studies, are compared. From laboratory tests can be mentioned triaxial shear test, direct shear test and for Fiber-reinforced soil typical pullout test. At the end of this thesis are said and compared material models available for Fiber-reinforced soil design.

Cílem této bakalářské práce byla sumarizace dostupných informací o zemině vyztužené rozptýlenými vlákny. V minulosti bylo po celém světě provedeno velké množství studií zabývajících se tímto tématem. Práce srovnává přístup jednotlivých řešitelů k tomuto problému co se týče vlastností výztuže – její materiál, rozměry a podíl v zemině. Všechny tyto parametry se ukázaly velmi různorodé, zatímco některé zdroje hovoří o vláknech malých rozměrů, jiné naopak o velkých rozměrech. Nejčastěji používaným materiálem se ukázal polypropylen, ačkoliv nebyl zdaleka jediným. Lze hovořit o různých přírodních, syntetických a dokonce i odpadních, jinak nevyužitelných, materiálech. Podíl vláken v zemině je v dostupných pracích uváděn několika způsoby, zde jsou tyto způsoby zhodnoceny a porovnány. Na zemině vyztužené rozptýlenými vlákny je také nutné provádět laboratorní zkoušky pro zjištění vlivu výztuže na inženýrské chování zeminy. Tyto zkoušky se ovšem od zkoušení nevyztužených zemin v některých parametrech liší, proto je na rozdíly upozorněno. Dále jsou shrnuty přístupy konkrétních řešitelů k testování. Z prováděných laboratorních zkoušek lze uvést triaxiální smykovou zkoušku, smykovou krabicovou zkoušku a pro zeminu vyztuženou vlákny specifickou zkoušku vytržení výztuže. V závěru jsou uvedeny a zhodnoceny materiálové modely dostupné pro navrhování zeminy vyztužené vlákny., The goal of this thesis was the summarization of available information about Fiber-reinforced soil. In the past, many of the previous works were published around the world. This thesis compares what type of fibres are in previous studies used – especially material, their size and amount in the Fiber-reinforced soil. All of these parameters were quite various, some of the sources used small-sized fibres, some used large-sized fibres. The most common material was polypropylene, although it was not the only one. For example, natural fibres, other synthetic materials, and waste materials can be mentioned. The amount of the fibres in the soil is measured in a few different ways, so in this thesis are these ways compared. It is necessary to run laboratory tests to quantify the effect of the fibres on the mechanical engineering properties of the soil. These tests are quite different compared to tests run on the unreinforced soil, so these differences are mentioned. The ways, how Fiber-reinforced soil was tested in different studies, are compared. From laboratory tests can be mentioned triaxial shear test, direct shear test and for Fiber-reinforced soil typical pullout test. At the end of this thesis are said and compared material models available for Fiber-reinforced soil design.

Cílem této bakalářské práce byla sumarizace dostupných informací o zemině vyztužené rozptýlenými vlákny. V minulosti bylo po celém světě provedeno velké množství studií zabývajících se tímto tématem. Práce srovnává přístup jednotlivých řešitelů k tomuto problému co se týče vlastností výztuže – její materiál, rozměry a podíl v zemině. Všechny tyto parametry se ukázaly velmi různorodé, zatímco některé zdroje hovoří o vláknech malých rozměrů, jiné naopak o velkých rozměrech. Nejčastěji používaným materiálem se ukázal polypropylen, ačkoliv nebyl zdaleka jediným. Lze hovořit o různých přírodních, syntetických a dokonce i odpadních, jinak nevyužitelných, materiálech. Podíl vláken v zemině je v dostupných pracích uváděn několika způsoby, zde jsou tyto způsoby zhodnoceny a porovnány. Na zemině vyztužené rozptýlenými vlákny je také nutné provádět laboratorní zkoušky pro zjištění vlivu výztuže na inženýrské chování zeminy. Tyto zkoušky se ovšem od zkoušení nevyztužených zemin v některých parametrech liší, proto je na rozdíly upozorněno. Dále jsou shrnuty přístupy konkrétních řešitelů k testování. Z prováděných laboratorních zkoušek lze uvést triaxiální smykovou zkoušku, smykovou krabicovou zkoušku a pro zeminu vyztuženou vlákny specifickou zkoušku vytržení výztuže. V závěru jsou uvedeny a zhodnoceny materiálové modely dostupné pro navrhování zeminy vyztužené vlákny., The goal of this thesis was the summarization of available information about Fiber-reinforced soil. In the past, many of the previous works were published around the world. This thesis compares what type of fibres are in previous studies used – especially material, their size and amount in the Fiber-reinforced soil. All of these parameters were quite various, some of the sources used small-sized fibres, some used large-sized fibres. The most common material was polypropylene, although it was not the only one. For example, natural fibres, other synthetic materials, and waste materials can be mentioned. The amount of the fibres in the soil is measured in a few different ways, so in this thesis are these ways compared. It is necessary to run laboratory tests to quantify the effect of the fibres on the mechanical engineering properties of the soil. These tests are quite different compared to tests run on the unreinforced soil, so these differences are mentioned. The ways, how Fiber-reinforced soil was tested in different studies, are compared. From laboratory tests can be mentioned triaxial shear test, direct shear test and for Fiber-reinforced soil typical pullout test. At the end of this thesis are said and compared material models available for Fiber-reinforced soil design.

Diplomová práce se zabývá statickou analýzou spojenou s výtokovým kanálem plavební komory. Podkladem pro práci byl návrh zesílení pomocí celozávitových předpínacích tyčí a výkresová dokumentace stávajícího stavu. Cílem práce bylo představení problematiky spojené s kotvením předpínacích tyčí soudržností ve stávající betonové konstrukci, zejména pak testování na zkušebních blocích v laboratoři pro ověření vhodného řešení. V návaznosti na získaná data provést analýzu a porovnání na modelech řešených nelineárním výpočtem v programu ATENA Science. Následně je provedena analýza modelu stávajícího stavu výseku výtokového kanálu rovněž nelineárním výpočtem s vyhodnocením jeho chování na extrémní zatížení. Tento model je následně doplněn o zesílení pomocí předpínacích tyčí s aplikací poznatků spojených s modely zkoušky vytržení. Model předepnutého výseku výtokového kanálu tak přestavuje simulaci provedení na samotné plavební komoře. Práce je doplněna o výkresy zkušebního bloku a zesílení výtokového kanálu., The thesis deals with the static analysis associated with the outlet channel of the lock chamber. The basis for the work was the design of reinforcement using full-threaded prestressing bars and the drawing documentation of the existing condition. The aim of the work was to present the issues associated with the anchoring of the prestressing bars by cohesion in the existing concrete structure, in particular testing on test blocks in the laboratory to verify a suitable solution. Following the data obtained, to perform an analysis and comparison on models solved by nonlinear computation in ATENA Science software. Subsequently, the analysis of the model of the existing condition of the outlet channel section is also carried out by nonlinear calculation with the evaluation of its behaviour to extreme loads. This model is then supplemented with reinforcement using prestressing bars with application of the knowledge associated with the pullout test models. The model of the pre-stressed outlet channel section is thus a simulation of the design on the lock itself.