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As an important infrastructure, the floating platform plays a significant role in coastal and oceanic development. The single‐point mooring system anchored by piles has been widely used to support floating offshore platforms. However, few studies in the field of floating structures focused on the dynamic reliability and mechanical analysis of the mooring pile foundation under wind and wave vibration. A Monte Carlo‐based mooring pile reliability analysis method was introduced in this paper, which could consume the calculation source significantly. Based on the Monte Carlo simulation, the dynamic reliability of the mooring pile system of the floating platform was analyzed and discussed. Finally, considering the material cost, the design of the mooring pile of floating platform was optimized. The simulation work presented here also will contribute to a deeper understanding of civil engineering works' pile foundation. [ABSTRACT FROM AUTHOR]

The primary objective of this case study is to evaluate the effectiveness of drone-based ground penetrating radar (GPR) in detecting and mapping underground water levels and soil-to-rock boundaries. This knowledge is crucial for accurate structural engineering analyses, including foundation engineering and site-specific response evaluations. The paper also considers drone-based GPR to overcome common urban obstacles, topographic variations, and environmental factors by simply flying over them, offering a promising solution to these challenges. The research utilized drone-based GPR equipped with an unshielded 150 MHz dipole antenna and employed filtering procedures to diminish the effect of above-ground obstacles on the interpretation of our results. The study unequivocally demonstrated the feasibility and effectiveness of drone-based GPR in these applications, reassuring the civil engineering community. The findings of this study significantly advance our understanding of drone-based GPR technology for mapping disturbed soil boundaries and water table levels in foundation engineering and site response applications and provide valuable recommendations for optimizing its performance in complicated terrains, thereby inspiring and guiding future research and practice in this field. [ABSTRACT FROM AUTHOR]

AbstractNowadays, the use of deep foundations in various civil engineering projects, especially in marine and coastal structures, has been increasing. One type of deep foundations are helical pile foundations, which have gained significant attention in recent decades. This research investigates the load–displacement behavior of different helical pile configurations regarding geometry, i.e., helix diameter and spacing ratio (S/D) in two different soil densities under pullout and compressive loading conditions via the FCV-AUT device. Babolsar sand from the southern coast of the Caspian Sea was utilized for advancing this study. Additionally, four full-scale pile tests were conducted on the Caspian Sea coast under both grouted and non-grouted conditions for pullout and compressive loading. The results indicate that increasing the helix diameter, soil density, and S/D ratio enhances the compressive load-bearing capacity. However, in tensile loading, the ultimate load decreases with an increase in the spacing ratio. Furthermore, the grouting process in the three-helix pile exhibits better performance compared to the two-helix pile, potentially increasing the pile capacity up to 30%. In conclusion, the results obtained from the FCV device, utilizing scale theory, have been generalized to the large-scale pile test results in the field, are representative of in agreement and compatible. [ABSTRACT FROM AUTHOR]

As the scale of underground rail transit construction in urban areas continues to expand, the tunnel construction environment has become progressively more complex. In recent years, an emerging artificial intelligence (AI) method in the civil engineering field, called the Random Forest (RF) method, has been widely used. In the construction of Zhengzhou Metro Line 7, the RF method was used to predict and control the vertical displacement of the bridge pier pile foundation. Such displacement can indicate the deformation of the structure, particularly under long-term utilization and strenuous circumstances that could sink or lift the pier body. Moreover, the vertical displacement of the bridge pier can affect the stiffness and bearing capacity of the bridge, thus impacting driving safety and the bridge's service life. Therefore, the vertical displacement of bridge piers has become the main prediction and control indicator for research. In the Zhengzhou Metro Line 7 tunnel, the tunnel continuously passes through 78 bridge pier foundations, among which the pile foundations of 4 key bridge piers are less than 0.5 times the tunnel diameter with a clear distance planned for the tunnel. However, limitations such as surface traffic and environmental conditions prevent the reinforcement of the bridge pier foundation in advance. Therefore, determining and setting sensible shield construction parameters is crucial to effectively controlling the vertical displacement of these essential bridge piers. This project can serve as a model for future endeavors. The study combines Random Forest with Particle Swarm Optimization Algorithm (PSO) to upgrade the technology of shield tunneling through Pier 2, introduces the Bayesian principle for statistical analysis, and optimizes various main construction variables. Random Forest is an ensemble learning method based on decision trees, which has high flexibility and predictive performance. It can automatically filter out important features from a large number of input features, thereby establishing an effective prediction model. The primary research objective is to enhance tunnel construction by accurately predicting and controlling the vertical displacement of pier foundations. To achieve this objective, the study utilizes the PSO to optimize the parameters and structure of the RF model. By doing this, the model's ability to predict the pier's vertical displacement accuracy can be improved. By combining these two methods, the accuracy of the prediction model and the optimization effect of construction parameters can be improved. In addition, the reliability of the model is further improved by using the Bayesian principle for statistical analysis. The paper compares and evaluates the engineering data objectively, presenting the evaluation index and feature selection method. This approach is innovative and purposeful, aiming to enhance the predictive ability, construction efficiency, and quality. This method can provide support for decision-making and optimization of engineering projects and promote sustainable development of the project. After the construction was completed, the model was established, and the results were predicted. The actual engineering measurement data of Pier Two was taken for comparison with it. Two parameters, Root-Mean-Square Error (RMSE) and Linear Curvature (R² ), were introduced to evaluate the prediction results, and the results were subjected to Correlation-based Feature Selection (CFS). The test sets for the downstream and the upstream tunnel were extracted, in which R² for the three extracted comparisons of the downstream were 0.83, 0.82, and 0.89, respectively, while R² for the upstream was 0.88, 0.86, and 0.86, respectively. From this, it can be seen that the optimized model has good predictive performance. In the construction process of other projects, the model can be used to predict the vertical displacement of bridge piers, which has real-time performance in preventing accidents. [ABSTRACT FROM AUTHOR]

Piled raft foundations are composite foundations that combine piles and raft to support civil engineering structure and to reduce the settlement. The data were obtained from Addis Ababa, Ethiopia. In this study, the effects of raft thickness, number of piles, pile length, spacing of piles, and pile diameter on the response of piled-raft foundations were investigated using the finite element-based program Plaxis 3D for layered soils (medium to very stiff high plastic silty clay and medium to very dense silty sand soil) subjected to uniform vertical loading. The results showed that increasing the thickness of the raft from 0.7 m to 1.7 m reduced the differential settlement by 78.21% when there were 16 piles. However, the maximum settlement also increased by 2.81%. Increasing the number of piles from 4 to 16 reduced the maximum settlement by 22.09% for a pile spacing of 4D. Moreover, increasing the pile length from 9 m to 15 m contributed to a 19.49% reduction in the total settlement for a pile spacing of 5D. Therefore, the current study provides a useful framework for analyzing and designing large piled-raft foundations. [ABSTRACT FROM AUTHOR]

The article discusses the S-LINK project, which aims to create a railway connection in the city center of Salzburg. The construction methods being considered include cut and cover construction and conventional tunnel construction with the use of jet grouting. The article also discusses the geological and hydrogeological conditions of the area and the challenges and solutions for implementing the construction methods. The document provides information about the construction of a tunnel in the city center of Salzburg. The tunnel is being built using a top-down construction method, with a jet grouting block being created to stabilize the surrounding soil. The document also mentions the use of Building Information Modeling (BIM) for the project and the challenges posed by existing buildings and utilities. The article discusses the S-LINK tunnel construction project in the city center of Salzburg. It highlights the challenges faced during the project and the solutions implemented. The paper emphasizes the collaboration between all parties involved in the project, which allowed for efficient investigation of the route and preparation of the necessary documents for the environmental impact declaration. [Extracted from the article]

The building industry faces a number of prominent challenges in the coming period. In this article, we focus on productivity in construction, which lags behind other industries despite technological developments. There is an urgent need for more efficient production methods. In other words, the potential for increasing productivity in construction is enormous. As in other industries, the key to this lies in process orientation, process standardization, and digitization. Lean construction approaches offer innovative solutions here by aiming to maximize customer value while minimizing waste, applying the principles of lean production to construction processes. However, building products are distinct in nature. Efforts to standardize them have achieved partial success, but only within specific product categories and for certain customer needs. Most construction activities remain highly unique. An alternative solution lies in standardizing work processes and not the final product. By adopting this method, one can considerably decrease individuality in production without compromising the essential uniqueness of the building product. Consequently, it is crucial to gain a deeper understanding of the standardization of production processes and the dynamics within the construction sector. This article introduces a modular construction toolkit designed to standardize production processes at construction sites. This toolkit consists of a series of consistent process steps, each linked to a standard time metric. Using this classification, a production model is constructed from a select number of recurring processes, leading to an ontological representation of production. This modular approach allows diverse production processes to be compared based on productivity, as they are composed of consistent and comparable sub-processes. Such a comparison is crucial for continuous production optimization. This method also enables the pinpointing of the most wasteful processes across various construction sites. While the primary data generation use case is centred on special civil engineering (special foundation engineering), the core concepts can be applied to general building construction. [ABSTRACT FROM AUTHOR]

Foundation plays a vital role in weight transfer from the superstructure to substructure. However, foundation characteristics such as pile group, piled raft, and footing remain unfolded due to their highly non-linear behaviour in different soil types. Bibliography analysis using VOSvierwer algorithm supported the significance of the research. Hence, this study investigates the load-bearing capacity of different types of foundations, including footings, pile groups, and piled rafts, by analyzing experimental data using finite element tools such as PLAXIS 2D and GEO5. The analysis involves examining the impact of various factors such as the influence of surcharge and the effect of different soil types on the load-bearing capabilities of the different types of foundation. For footing, parametric investigations using PLAXIS 2D are conducted to explore deformational changes. Pile groups are analyzed using GEO5 to assess their factor of safety (FOS.) and settling under various criteria, such as pile length and soil type. The study also provides insight into selecting the right type of foundation for civil engineering practice. Findings showed that different soil types have varying deformational behaviours under high loads with sandy soil having less horizontal deformation than clayey soil. Also, it was observed that increasing the pile thickness by 50% resulted in a reduction of 13.88% in settlement and an improvement of 16.66% in the FOS. In conclusion, this study highlights the importance of professionalism, exceptional talent, and outstanding decision-making when assessing the load-bearing capabilities of various foundation types for building structures. [ABSTRACT FROM AUTHOR]

Paper [[14]] proposed a response surface method to further improve the accuracy of alignment prediction for large-span steel-concrete composite beam track cable-stayed bridges. Paper [[5]] investigated the effect of pile foundation cutting and under-pinning processes on the stability of bridge substructures during shield tunneling. They utilized numerical simulations and on-site monitoring to study how the active underpinning process of shield tunneling pile foundations affected bridge substructure deformations. [Extracted from the article]

The degradation of concrete structures is often due to the continuous application of compressive fatigue loads. Understanding of concrete behaviour in different environmental conditions and under especial fatigue loading arrangements, particularly in cases where the loaded area is smaller than loaded element, herein referred to as partially loaded area, is of utmost importance to make a realistic prediction of the concrete fatigue life for a reliable design of civil engineering infrastructure. This paper focuses on investigating the fatigue performance of reinforced concrete specimens subjected to partially loaded areas, considering the influences of steel fibres, reinforcement arrangement, and the environmental factor of water submergence. A typical example of a partially loaded concrete component subjected to fatigue loading is circular spread footings used as concrete foundations for typical wind turbines. In these types of elements, the compressive strength of the concrete can be enhanced due to the confinement provided by way of lateral restraint stemming from surrounding concrete and reinforcement. However, design codes primarily address static loading and lack specific criteria for fatigue loading in these partially loaded regions. To address this research gap, results from a comprehensive experimental study, which in total included 111 concrete specimens subjected to monotonic loading and 25 specimens tested under cyclic loading, were used to study this problem. The investigation aimed to evaluate the effects of steel fibres and reinforcement arrangement on both static and fatigue capacity. Additionally, the impact of submerging concrete structures in water on their fatigue performance was examined, revealing a decrease in their fatigue life. The experimental results demonstrated that the presence of steel fibres and splitting reinforcement significantly increased both static and fatigue capacity. Most current design codes neglect the environmental factor of water submergence, leading to reduced fatigue capacity in concrete structures. Consequently, the validity of the design codes DNV-OS-C502 and fib Model Code 2010 was evaluated, and a new environmental factor for partially loaded areas subjected to cyclic loading is proposed. To evaluate the experimental results and understand the mechanical response, nonlinear finite element analyses were conducted using a smeared-crack continuum modelling procedure coupled with high cycle fatigue material models to assess its applicability for estimating fatigue performance of partially loaded reinforced concrete elements. It was found that a plane stress modelling procedure was capable of estimating fatigue capacity for dry concrete components, however, overestimated the fatigue capacity of wet concrete components. • Fatigue of reinforced concrete specimens under partially loaded conditions. • Effect of steel fibres, reinforcement arrangement, and water submergence on fatigue. • Reduction in fatigue life due to the environmental impact of water submergence. • Proposing a new environmental factor for fatigue of concrete structures. • Utilizing NFEA with smeared-crack continuum modeling for numerical fatigue assessment. [ABSTRACT FROM AUTHOR]

• A new seismic barrier for underground structures is proposed to control the Rayleigh waves. • The soil acceleration response is reduced within the frequency range of 0.5–5 Hz. • The maximum layer drift of the subway station is reduced by over 40 %. • The internal forces of structural components are reduced by 70 % on average. • A novel index is proposed to evaluate the performance of seismic barriers. This research introduces a novel seismic mitigation approach for civil engineering constructions, utilizing seismic metamaterials, and particularly studies its application to underground structures. This approach involves the implementation of a regional seismic barrier, designed in the form of piles periodically clamped to a concrete foundation. The efficacy of this seismic barrier is explored through comprehensive numerical simulations. A wave propagation study is conducted to investigate the attenuation efficiency for Rayleigh waves in the frequency domain. Besides, dynamic analysis is performed on a two-layer and three-span subway station subjected to actual seismic recordings. The results from the wave propagation study reveal a notable reduction in acceleration response within the frequency range of 0.5 Hz–5 Hz when employing the seismic barrier, in contrast to the free-field scenario. Dynamic analysis demonstrates that the implementation of the proposed seismic barrier leads to a significant decrease in both the maximum layer drift and the structural internal forces of the subway station. Moreover, the relative displacement of soil proves to be a pertinent metric for evaluating the seismic control efficacy of the proposed barrier for underground structures. [ABSTRACT FROM AUTHOR]

S21 PfA 1.3a – construction planning of the airport connection The construction project "S21 airport connection PfA 1.3a" is part of the major project Stuttgart–Wendlingen–Ulm and includes about 5 km of the high‐speed line along the A8 motorway as well as the connection to Stuttgart Airport. The construction work includes, among other things, 1.4 km of troughs and tunnels in open construction, 3.5 km of tunnels in mining construction, twelve bridges and culvert structures as well as the incision and dam structures of the new line. With the execution of the excavation pits as well as the special foundation engineering work, numerous interfaces to the civil engineering, the railway construction and the existing structures are created. In the transition area between tunnels in open construction and mining construction, complex combined pit systems with ground anchors, rock nailing, bracings and "Totmann" constructions result due to the construction process. The railway line is based on the backfilling and the engineering structures of the troughs and tunnels in open construction. The challenging task in the production of the piles for the foundation of the railway overpass on the B312 was the immediate proximity of the foundation piles to the existing trough. The transfer of horizontal bedding forces to the trough is prevented by the creation of an annular gap between the foundation pile and the subsoil. Essentially, the following report will reflect the planning of the excavation pits and the associated interfaces within the framework of the S21 PfA 1.3a airport tunnel project. For this purpose, a holistic view of the execution planning is required. [ABSTRACT FROM AUTHOR]

Vibrating technological equipment for the introduction of piles and columns into the ground of construction foundations (named vibratory piling machines) is crucial in the process of building stable and resilient foundations for civil engineering, hydrotechnical construction, special construction (e.g., military constructions), bridges, roads and industrial platforms. During the works carried out by the construction companies in various geographical areas of Romania, particularities of the dynamic technological regimes influenced by the nature of the land were identified at the deep introduction of the construction elements in the form of piles or circular (tubular) columns. The results of applied research, rheological modeling and optimization of vibrating equipment, highlight the need for an analytical approach that takes into account the parametric variations of the elastic and damping characteristics of some categories of soils on the depth of piles or foundation columns. In this context, the paper presents the calculation model with the dynamic response for the vibrating equipment of insertion with disturbing forces of 200–1250 kN for piles or columns with lengths of 10–30 m. The novelty of the research study consists in the linear rheological model, which was adopted in the form of a Maxwell–Voigt–Kelvin schematic of the type (E-V)–(E|V), with a discrete variation in four values for stiffness and damping of the soil, as the piles or columns vibrate and advance in the ground foundation. Practical experience of the authors in the field of using vibrogenerators for the introduction of piles in various types of ground foundations led to the adoption of the rheological model with variable damping coefficients depending on the depth of penetration into the soil. The curves of the dissipated power confirm the experimental data obtained in situ, in accordance with the rheological indoor tests of the different types of soil foundations. [ABSTRACT FROM AUTHOR]

In many civil engineering projects, Piled Raft Foundations (PRFs) are usually preferred where the incoming load from the superstructures is very high. In geotechnical engineering practice, the settlement of soil layers is a critical issue for the serviceability of the structures. Thus, assessment of risk associated with the structures corresponding to the maximum allowable settlement of soils needs to be carried out in the design phase. In this study, reliability analysis of PRF based on settlement criteria is performed using a high-performance hybrid soft computing model. The new approach is an integration of the artificial neural network (ANN) and a recently developed meta-heuristic algorithm called equilibrium optimizer (EO). The concept of reliability index was used to explore the feasibility of a newly constructed hybrid model of ANN and EO (i.e., ANN-EO) against the conventional approach of calculating the probability of failure of PRF. Experimental results show that the proposed ANN-EO attained the most accurate prediction with R2 = 0.9914 and RMSE = 0.0518 in the testing phase, which are significantly better than those obtained from conventional ANN, multivariate adaptive regression splines, and genetic programming, including the ANN optimized with particle swarm optimization developed in this study. Based on the experimental results of different settlement values, the newly constructed ANN-EOis very potential to analyze the risk associated with civil engineering structures. Also, the present study would significantly contribute to the knowledge pool of reliability studies related to piled raft systems because the works of literature on reliability analysis of piled raft systems are relatively scarce. [ABSTRACT FROM AUTHOR]

Zhu, R.; Wang, Q.; Zheng, J.; Su, J., and Wang, N., 2021. Damage detection of pile foundations in marine engineering based on a multidimensional dynamic signature. Journal of Coastal Research, 37(3), 576–588. Coconut Creek (Florida), ISSN 0749-0208. Compared with land engineering, pile foundations in marine engineering have the characteristics of long, free lengths in water and bad service environments. The traditional methods of pile foundation damage detection have considerable limitations in the application in marine engineering. In this paper, a new method for pile foundation damage detection is developed. The method constructs a multidimensional dynamic signature space by fusing multivariate information, uses the Mahalanobis distance to define the difference between the damaged and undamaged units of the structure, and detects damage based on a robust outlier identification method in multidimensional space to realize reliable and automatic damage detection under high noise and complex conditions. The effectiveness and reliability of the method are verified using a finite element model (FEM) of a high-pile wharf under different damage degrees and different intensities of Gaussian white noise. The applicability of the method is then experimentally validated on a physical experimental model of a high-pile wharf. Both the FEM and the experimental results show that the method is capable of detecting pile foundation damage and has strong application potential. [ABSTRACT FROM AUTHOR]

On February 6, 2023, two devastating earthquakes occurred on the East Anatolian Fault, Turkiye. The earthquakes had severe impacts on civil engineering structures in Iskenderun, Hatay. Reconnaissance studies were performed in Iskenderun to document and evaluate the performances of the different foundation systems and improved ground. Several soil liquefaction cases, including a boulevard, a mosque complex, fishing shelter, and military quarters were observed and documented along with the ground conditions and surface ejecta characteristics. The site observations during the reconnaissance study showed that the application of the unreinforced concrete piles was not a proper foundation solution against seismic loading and did not perform well. Whereas foundation systems including reinforced barrette piles and improved sites with jet grout columns were observed to perform quite well with negligible/no deformations. Observations at several structures indicate that conventional pile foundations also performed well, however structures built on deep foundation systems together with prior jet grout improved sites performed notably better. • February 6 earthquakes had severe impacts on engineering structures in Iskenderun. • This is a reconnaissance study which discusses liquefaction cases in Iskenderun. • Additionally, seismic performance of various foundation systems were evaluated. • 28 buildings were evaluated in-terms of foundation type and the observed damage. • Structures supported by deep foundations and ground improvement performed notably better. [ABSTRACT FROM AUTHOR]

Nowadays, the environmental assessment becomes more and more of interest as an additional tool for the decision-makers. The researchers in civil engineering focus on building materials, structures as well as whole buildings environmental evaluation. Analysis of the environmental impact of particular structures may be helpful for selecting building materials, with regard to the environmental performance of buildings in the early project phase. The aim of this paper is presentation of an environmental evaluation of the rarely assessed particular structures – building foundations and the analysis of the share of the building foundations to the overall environmental impact of building as well. The obtained data point to the need to include the environmental impacts of foundations when assessing the buildings, because of it is a necessary part of any type of family house. One kilogram of built-in foundations materials was responsible for emissions of 0.092 kg of greenhouse gases expressed by carbon dioxide (CO2). Embodied energy was calculated as equal to 1.14 MJ per 1kg of foundations materials and 832.2 MJ/m2 per building floor area. The foundation materials of houses contributed to the total environmental impact of the whole buildings by, on average, 15.0 and 22.8 % for embodied energy and global warming potential, respectively. [ABSTRACT FROM AUTHOR]

Problematic soils exist almost everywhere on the globe. State-of-the-art solutions to make civil engineering infrastructures built on them are still highly sought. The CFG (cement-fly ash-gravel) pile composite foundation system has been widely used in buildings, highways, railways, and bridge transition sections owing to its proven engineering characteristics in soft ground treatment. This paper discusses about the development and achievements of its engineering applications, along with possible future research directions. The remarkable evolution took place in the past to address projects' strict differential and postconstruction settlement control requirements including embedding the geosynthetic layer into the load transfer platform and combining it with rigid slabs, as seen implemented in few CFG pile-supported embankments. It was also observed that the interaction of the existing CFG pile composite foundation with an adjacent new foundation pit excavation inevitably presents a complex soil-structure interaction mechanism among the fundamental components—the retaining wall, mat, piles, cushion, and soil. [ABSTRACT FROM AUTHOR]

The aim of this paper is to show the influence of the subgrade reaction coefficient modelling on the simple 3D frame subjected to horizontal symmetrical static load. Since the work represents a continuation of the research on this topic, it was decided that the construction, in this case too, was built on the square foundations on granular soil. Different values of subgrade reaction coefficient obtained for the square foundation are the consequence of using different expressions defined by individual authors. Thus, one diagram shows each author's relation between the width of the foundations and the value of the subgrade reaction coefficient. The response of the characteristic structural framework additionally loaded with horizontal static force is then described further in the paper. [ABSTRACT FROM AUTHOR]

Foundation strengthening/new foundations to the historically sensitive structure of the Pergamon Museum on the Museum Island in central Berlin. The three‐wing building for the presentation of mostly large classical objects was built between 1910 and 1936 and after 100 years requires thorough refurbishment. In order to regain complete museum functionality and provide the correct climatic conditions for the exhibited objects, extensive strengthening measures, new foundations and lowering of the basement inverts are unavoidable. The extensive archived documents showed that the Pergamon Museum is founded at several levels at a depth of between 6 and 18 m below ground level. The deep geological scouring in the foundation formation led to great problems with the planned raft foundation after soil exchange under the protection of dewatering. The available results of the soil survey from 1912 in the area of the south wing, which until then had been built over, showed that the organic scouring extended down to about –12 m below sea level. This demanded a fundamental alteration of the foundation in this building section. Neither the dewatering plant nor the deep foundation elements available in 1912 were capable of reaching the loadbearing ground about 45 m below ground level. The stringent requirements for the deformation behaviour of the existing structures and in particular the south wing of the Pergamon Museum, which remained in use during the refurbishment works, required appropriate monitoring of reactions, which had to be constantly compared during the construction works. Both vibration and settlement curves were recorded and used as a decisive criterion for the selection of possible refurbishment technologies from specialised civil engineering. The solutions selected on site, both in the completion phase and in the current refurbishment phase, are described and discussed in this article. [ABSTRACT FROM AUTHOR]

Vp/Vs and Poisson's ratio (σ) of subsurface strata are important parameters in the foundation study for the assessment of lithology, quality and strength of the rock, structural disturbances and saturation condition prior to the construction of huge civil structure like Nuclear Power Plant. The present work in this paper, showing the evaluation of overburden thickness, assessing quality and compactness of rock and identifying structural disturbance using Vp/Vs and Poisson's ratio, is based on the fact that Vp/Vs is a better indicator of lithology (Mokhtar et al. in Porosity and heterogeneity effect on Vp/Vs ratio in carbonate rocks from a reservoir in the Middle East, Milan, 2012) than individual velocity values i.e. Vp and Vs. Moreover Vp/Vs and Poisson's ratio both indicate the quality of rock (Bahremandi et al. in J Sci Res Rev 12:015-019, 2012) and structural disturbances within rock in terms of cracks, fractures or joints (Barton in Rock quality, seismic velocity, attenuation, and anisotropy, Taylor & Francis, London, 2006) etc., which is helpful in deciding the load bearing capacity of the foundation. The value of Vp and Vs, used in this paper, are taken from four research papers where Vp and Vs as a function of depth are studied with examples of Kalpakkam Nuclear Power Project, Tamilnadu (Boominathan in Curr Sci 87(10):1388-1397, 2004), Kakrapar Atomic Power Plant, Gujarat (Wadhwa et al. in J Ind Geophys Union 13(1):9-16, 2009), Kaiga Atomic Power Plant, Karnataka (Wadhwa et al. in J Ind Geophys Union 14(1):21-30, 2010) and Tarapur Atomic Power Plant, Maharashtra (Wadhwa et al. in J Ind Geophys Union 9(2):137-146, 2005) in Indian subcontinent. [ABSTRACT FROM AUTHOR]

The lower bound depth of the self-weight collapse of loess is used to determine the type and grade of a collapsible loess foundation. It is important to select a reasonable foundation treatment depth and to determine negative skin friction neutral points of the pile. This study comprehensively analyses the differences between laboratory and full-scale field testing in determining the lower bound depth of the self-weight collapse of loess. Although this lower bound depth tends to be a unique value, obvious differences were obtained in the test results obtained by the two methods. Generally, the laboratory test results were 1·25-2·90 times greater than those of the field test, mainly owing to differences in saturation, test pressure, the sample stress state and soil non-uniformity. Evaluation of the lower bound depth of the self-weight collapse of loess should therefore be based on field testing and the results from laboratory tests need to be modified. This paper puts forward a new theoretical modification method for this purpose, which could reduce the differences between laboratory and field test results. [ABSTRACT FROM AUTHOR]

The present research aims to measure and analyze the most reliable stress and strain distributions transferred in bored piles embedded within multilayer site conditions. Extensive data are summarized to measure changes in the stresses and strains in a bored pile. The effect of weak geological zones on multilayer site conditions can significantly change the design criteria since most of the dominant factors change with depth. [ABSTRACT FROM AUTHOR]

In the last decade piled raft foundations have been widely used around the world as intermediate foundation systems between piles and rafts to control the settlement of foundations. However, when those piles are structurally connected to rafts, relatively high axial stresses develop in relatively small numbers of piles, which are often designed to fully mobilize their geotechnical capacities. To avoid a concentration of stress at the head of piles in a traditional piled raft foundation, the raft is disconnected from the piles, and a cushion is introduced between them. Also, to tackle an unfavourable soil profile for a piled raft foundation, the conventional piled raft has been modified into a cushioned composite piled raft foundation, where piles of different materials are used. In the current study the behavior of cushioned foundation components, which transfer the load from the structure to the subsoil, are analyzed in detail, i.e., the thickness of the raft, the length of a long pile and the modulus of a flexible pile. [ABSTRACT FROM AUTHOR]

SUMMARY The present study addresses a layout design of rockbolts for reinforcing natural ground structures applying a special optimization method, called multiphase layout optimization. Rockbolts are used to tighten loosed natural ground, and the layout of rockbolts are determined without sufficient information about the physical properties of the ground materials. Because of this uncertainty, unexpected deformation often occurs at the excavation surface of natural ground. In that case, it is requested to determine an effective layout of the additional rockbolts promptly with respect to the actual deformation at the construction site. However, it is not easy to determine the optimal layout because of its complexity, and consequently, it has no choice but to determine the layout in an empirical way. This study introduces a numerical approach to determine an optimal layout of rockbolts with respect to arbitrarily possible deformation of natural ground. The objective is to maximize the stiffness of the overall ground structure reinforced with rockbolts. For optimization, a gradient-based optimization scheme is applied because of its numerical efficiency. It was verified from a series of numerical examples that this method has great potential to improve the stiffness of the overall ground structure and shows a certain applicability to a practical design. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highlights: [•] The obtained equation is very useful to build a structure above tunnels. [•] The equation is S =(−0.06A −1 CD 3)+(0.0116A −1 B 3 C)+(16AD −2)−12.12. [•] The influence radius at a point close to the tunnel is about 2.3D. [•] Increasing the number of stories from 4 to 6 causes the settlement to be doubled. [Copyright &y& Elsevier]

Creep settlement is an important aspect to consider where development is planned over deep compacted fill. This paper presents a case study of an earthworks design for infilling a quarry pit with sandstone and shale derived material and a comparison of predicted and monitored creep settlements. Laboratory testing was carried out during filling to assess the creep characteristics of available infilling materials. Based on the laboratory testing the influence of saturation on creep rates is discussed. Settlement monitoring points across the infilled quarry were monitored for up to 455 days. Predicted creep rates based on the results of the testing are compared with predictions based on monitoring. Monitored settlements within a few years of fill placement were variable and substantially greater than predictions based on the laboratory testing. Longer term monitoring data indicates that settlements are likely to be less than predictions based on laboratory testing. The results suggest that predictions over 30 years based on laboratory testing are conservative and lie within the normal range of accuracy of geotechnical predictions. [ABSTRACT FROM AUTHOR]

Laws governing formation of the stress-strain state of a "horizontally loaded foundation/ bed" system are examined. Results of experimental investigation of combined foundations with inclined precast piles sunk into a tamped-in pit are presented, and proposals are given for formulation of a computational scheme. [ABSTRACT FROM AUTHOR]

Abstract: This paper explains the basic principles related to design prediction for stress-and-strain state of load-bearing structures taken into account the stage-wise closing of the load-bearing structures system and changing the stiffness properties for members of the design model, external constraints, time histories of the pattern and values of loadings, time histories of nature of interaction between foundation- mounted load-bearing structures and foundation structures. [Copyright &y& Elsevier]

Abstract: Load-settlement relationships of shallow foundation models with different vertical cross-sectional shapes on different modeled subsoil conditions are presented. Model of shallow foundations with rectangular, wedge and T-shape vertical cross-sections were studied. The study generally shows that bulk of the load resistance of subsoil bases at the instance of shallow foundations with rectangular vertical cross-sectional shapes is mostly associated with the soil beneath the foundation base, while at the instances of those with wedge and T-shape vertical cross-sectional shape, both soil beneath the foundations’ bases and along their vertical stems, is actively involved in the resistance of structural loads. [Copyright &y& Elsevier]

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Abstract: A theoretical solution is developed for calculating the consolidation of foundations reinforced by geosynthetic-encased stone columns (GESC). The elastic volumetric strains of the column and the surrounding soil previously obtained by the authors are adopted, and both the horizontal and vertical flows within the column and the soil are considered in this solution. The solution for calculating the consolidation of the type-column composite foundation without geosynthetics is obtained by degenerating the present solution to this special case and compared it with existing solutions. The comparisons show that, as underestimating the volumetric strains of the column and the surrounding soil, the average degree of consolidation calculated by the previous studies are greater than the present model and the differences are noted. Finally, the influence of geosynthetics on the consolidation of composite foundation is analyzed. The results show that the geosynthetics encasement has negligible effect on accelerating the consolidation of the composite foundation in the elastic phase. [Copyright &y& Elsevier]