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The design of cantilever pile walls (CPWs) presents several common challenges. These challenges include soil variability, groundwater conditions, complex loading conditions, construction considerations, structural integrity, uncertainties in design parameters and construction and monitoring costs. Accordingly, this paper is to provide a detailed literature review on the design criteria of CPWs, specifically in cohesionless soil. This study aims to present a comprehensive overview of the current state of knowledge in this area.

The paper uses a literature review approach to gather information on the design criteria of CPWs in cohesionless soil. It covers various aspects such as excavation support systems (ESSs), deformation behavior, design criteria, lateral earth pressure calculation theories, load distribution methods and conventional design approaches.

The review identifies and discusses common challenges associated with the design of CPWs in cohesionless soil. It highlights the uncertainties in determining load distribution and the potential for excessive wall deformations. The paper presents various approaches and methodologies proposed by researchers to address these challenges.

The paper contributes to the field of geotechnical engineering by providing a valuable resource for geotechnical engineers and researchers involved in the design and analysis of CPWs in cohesionless soil. It offers insights into the design criteria, challenges and potential solutions specific to CPWs in cohesionless soil, filling a gap in the existing knowledge base. The paper draws attention to the limitations of existing analytical methods that neglect the serviceability limit state and assume rigid plastic soil behavior, highlighting the need for improved design approaches in this context.

This paper aims to investigate single pile and pile group responses due to deep braced excavation-induced soil movement in soft clay overlying dense sand. The analysis focuses first on the response of vertical single pile in terms of induced bending moment, lateral deflection, induced axial force, skin resistance distribution and pile settlement. To better understand the single pile behaviour, a parametric study was carried out. To provide further insights about the response of pile group system, different pile group configurations were considered.

Using the explicit finite element code PLAXIS 3 D, a full three-dimensional numerical analysis is carried out to investigate pile responses when performing an adjacent deep braced excavation. The numerical model was validated based on the results of a centrifuge test. The relevance of the 3 D model is also judged by comparison with the 2 D plane strain model using the PLAXIS 2 D code.

The results obtained allowed a thorough understanding of the pile response and the soil–pile–structure interactions phenomenon. The findings reveal that the deep excavation may cause appreciable bending moments, lateral deflections and axial forces in nearby piles. The parametric study showed that the pile responses are strongly influenced by the excavation depth, relative pile location, sand density, excavation support system and pile length. It also showed that the response of a pile within a group depends on its location in relation to the other piles of the pile group, its distance from the retaining wall and the number of piles in the group.

Unlike previous studies which investigated the problem in homogeneous geological context (sand or clay), in this paper, the pile response was thoroughly studied in a multi-layered soil using 3 D numerical simulation. To take into account the small-strain nonlinear behaviour of the soil, the Hardening soil model with small-strain stiffness was used in this analysis. For a preliminary design, this numerical study can serve as a practical basis for similar projects.

Deep excavation in soft clay often causes additional deformations to surroundings. Then, if deformations cannot be predicted reasonably, the adjacent buildings may be threatened by the deep excavation. Based on the good field observations from ten deep excavations in Hangzhou, this paper aims to thoroughly investigate the characteristics of wall deflections and ground settlements induced by deep excavations.

On the basis of good field observation of ten deep excavations, the performances of excavations, supported by contiguous pile in Hangzhou, were studied, and also compared with other case histories.

The maximum wall deflections (dhm) rang mostly from 0.7 to 1.2 per cent H_e, where He is the final excavation depth, larger than those in Taipei and Shanghai. The observed maximum ground settlement in the Hangzhou cases generally ranges from 0.2 to 0.8 per cent H_e. Then, the settlement influence zone extends to a distance of 2.0-4.0 H_e from the excavation. The relatively large movements and influence zones in Hangzhou may be attributed to low stability numbers, large excavation widths and the creep effect. The excavation width is justified to have a significant influence on the wall deflection. Therefore, to establish a semi-empirical formula for predicting the maximum wall deflection, it is necessary to include the factor of excavation width.

The relevant literature concentrated on the characteristics of deep excavations supported by the contiguous pile wall in Hangzhou soft clay can rarely be found. Based on the ten deep excavations with good field observation in Hangzhou, the characteristics of wall deflection and ground settlements were comprehensively studied for the first time, which can provide some theoretical support for similar projects.

Urban excavations are a cause for concern in terms of the probability of damage to nearby structures. In this study, various structural and excavation parameters were investigated to determine the probability of building damage during excavations.

Finite-element analysis software was used to develop a set of valid three-dimensional models. Models were developed to assess the effects of structural parameters (building height and position relative to the excavation site) and excavation parameters (depth and support system type) on the responses of the adjacent buildings.

The new design charts estimated the damage to reinforced concrete frame buildings during excavation by focusing on the angular distortion of the building, additional shear strain on the masonry walls and additional strain and stress on columns. This study showed that the probability of damage decreased as the distance between the building and the excavation increased. By contrast, it increased when the building was located at a distance equal to the excavation depth at its edge. According to this study, the axial stress caused by the excavation of building columns does not exceed 10.9% of the compressive strength of the concrete.

The proposed design charts can replace comparable charts and provide a deeper understanding of damage potential based on key parameters. These charts are more practical than previous charts with limited parameters.

Anchorage with concrete bearing pad is commonly used in Iran for stabilization of excavations because of the ease of construction, less costs and less time consumption than the soldier pile method. In this method, a wall facing which includes the concrete bearing pads at the location of the anchors and a shotcrete layer between the bearing pads is constructed parallel to the excavation operation similar to the nailing method.

In this paper, using the finite element software Abaqus, a three-dimensional model of the above-mentioned type of wall is constructed, and the effect of spacing and size of bearing pads on the wall behavior is discussed.

According to the obtained results, the size of the concrete bearing pads has little effect on wall deformations, but the internal forces and bending moments developed in the shotcrete layer between the bearing pads are greatly influenced by the bearing pads dimensions and spacing.

Owing to the discrete elements of the wall facing, the behavior of this system is completely three-dimensional.

The purpose of this paper is to timely control of a construction collapse accident effectively during its development process by constructing a stage model and then aligning IT with each stage to help provide the information for decision making.

Through comprehensive literature review, this paper first identifies the various IT applications in on-site construction monitoring and analyzes the existed disaster/crisis stage models, also the stage models are compared with the causation models to illustrate the strengths. Then, a three-step methodology was conducted to develop and apply the conceptual framework, including the construction of the four-stage model; the establishment of the conceptual framework of information technology (IT) support for management of construction accidents (ITSMCA); and a building collapse accident used to illustrate the proposed framework.

The accident is divided into four stages, which are incubation stage, outbreak stage, spreading stage and final stage. The real-time staged information to support decision making, such as the contributing factors of on-site workers, materials, equipment and workplace, can be provided by emerging IT. Therefore, IT is aligned with the variations of contributing factors’ attributes in the four stages and ITSMCA is constructed to help accidents management.

The focus of the framework presented in this paper is that the stage model is effective for it catches the variations of the attributes whose values can be provided by IT rather than research on the practical application of the IT system. The construction and application of the IT system will be the research focus in the future.

This paper presents a stage model of a building collapse accident and gives a comprehensive conceptual framework of ITSMCA, which align the IT with different stages of the collapse accident. The ITSMCA proposes a feasible ideology and practical method for real-time management of the collapse accident during the process.

To predict the real behavior of the full-scale model using a scale model, optimized simulation should be achieved. In reinforced concrete (RC) models, scaling can be substantially more critical than in single-material models because of multiple reasons such as insufficient bonding strength between small-diameter steel bars and concrete, and excessive aggregate size. Overall, there is a shortfall of laboratory and field-testing studies on the behavior of secant pile walls under lateral and axial loads. Accordingly, the purpose of this study is to investigate the validity and the performance of the 1/10th scaled RC secant pile wall under the influence of different types of loading.

The structural performance of the examined models was evaluated using two types of tests: bending and axial compression. A self-compacting concrete mix was suggested, which provided the best concrete mix workability and appropriate compressive strength.

Under axial and bending loads, the failure modes were typical. Where the plain and reinforced concrete piles worked in tandem to support the load throughout the loading process, even when they failed. The experimental results were relatively consistent with some empirical equations for calculating the modulus of elasticity and critical buckling load. This confirmed the validity of the proposed model.

According to the analysis and verification of experimental tests, the proposed 1/10th scaled RC secant pile model can be used for future laboratory purposes, especially in the field of geotechnical engineering.

The purpose of this study is to present a diagram for the lateral earth pressure of c–φ soils exerted on anchored walls in presence of surcharge.

To this end, two-dimensional plane strain modeling of anchored wall was carried out in Plaxis software. To validate the numerical model, two excavations with different specifications were simulated and the model results were compared with the available results. Subsequently, a parametric analysis was done and based on its results, a diagram was proposed for the lateral earth pressure of c–φ soils including the surcharge effects.

The proposed diagram without the surcharge and cohesion effects is a trapezoidal with zero value at the ground surface that is linearly approaching the apparent earth pressure of sand according to Terzaghi and Peck (1967) at 0.1H (H: wall height). The surcharge and cohesion effects at the ground level is 4 Ka*q and 0, respectively, and below 0.1H, they are treated as the same way for lateral earth pressure of a retaining wall. It should be emphasized that the apparent pressure diagram for design does not resemble the real distribution of earth pressure against the wall and it is for calculating the values of the anchors loads.

The available diagrams to determine the earth pressure exerted on the anchored walls are related to sandy or clayey soils and do not take the presence of surcharge into account. Thus, the proposed diagram is quite original and different from the previous ones.

A quantitative approach for construction pollution control that is based on construction resource levelling is presented. The parameters of construction pollution index (CPI) and hazard magnitude (hi) are treated as a pseudo resource and integrated with a project’s construction schedule. When the level of pollution for site operations exceeds the permissible limit identified by a regulatory body, a Genetic Algorithm (GA) enhanced levelling technique is used to re‐schedule project activities so that the level of pollution can be re‐distributed and thus reduced. The GA enhanced resource levelling technique is demonstrated using 20 on‐site construction activities in a project. Experimental results indicate that the proposed GA enhanced resource levelling method performs better than the traditional resource levelling method used in MS Project©. The proposed method is an effective tool that can be used by project managers to reduce the level of pollution at a particular period of time; when other control methods fail.

In the construction sector, site excavation is one of the most dangerous and challenging activities. Proper training can be an effective way to mitigate excavation hazards. Virtual reality (VR) has been used as an effective training tool to enhance safety performance in various industries. However, little attention has been paid to the potential of this technology for construction excavation safety training.

This study proposes an immersive VR training system for excavation safety and hazard identification. The proposed VR training system was compared with a health and safety manual via a controlled experiment.

Results based on scores obtained immediately after training indicate that VR training significantly enhanced practical performance, knowledge acquisition and self-efficacy. Results also show that knowledge was retained four weeks after training. In addition, VR training outperformed health and safety manuals regarding knowledge retention.

This study measures the practical performance to evaluate the effectiveness of the proposed VR training system. Also, this study compares the VR training system with a traditional training method by measuring knowledge acquisition and retention. The results demonstrate the potential of VR as a training tool for excavation safety and hazards.