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In the past decades, as the world has placed emphasis on green energy, solar energy has become a favorable option. Different piled foundations have been designed to strengthen the structure supporting the solar panels. These piled foundations include rectangular and circular hollow section piles, as well as H-shaped piles. With various environmental loadings, lateral soil displacement will be encountered when large solar panels are installed on the supporting structure at an inclined angle. Presently, helical pipe piles are widely used in solar farms as part of the supporting structure. In this paper, the pile–soil interaction of steel pipe piles and helical pipe piles with wind loads is analyzed using ABAQUS. The Finite Element Method (FEM) models are assessed with varying strength moduli and cohesions of clay. Further, this paper examines the pile soil system, considering different clay stiffnesses, including very soft, soft, firm, stiff, very stiff, and hard. It is found that the helical piles' horizontal capacity increases with soil strength and Young's modulus, but the capacity increment rate reacts differently. This study has a guiding effect on the construction of solar farms using the "tracker" solar system. [ABSTRACT FROM AUTHOR]

There is currently a pressing need for rental housing to be built and the Build-to-Rent (BTR) market is growing to address such housing demands. Existing research focuses on the financial and planning aspects of existing BTR markets. However, more research is needed to clarify the responsibilities and strategies of key stakeholders to achieve success in BTR developments. Moreover, as an emerging topic, identifying the key themes of research and future directions may be beneficial for the body of knowledge. This study critically analyses the existing research published on BTR and aims to identify their key themes and recommend strategies, via a conceptual framework, for achieving success in BTR developments. Systematic literature review methodology was employed to identify recent publications on the topic of BTR, utilising the databases Web of Science and Scopus. A total of 58 research publications from 2013 to 2023 were identified. Using Leximancer software, the identified literature was systematically and thematically analysed. The analysis identified four themes: (1) stakeholders' influences on the uptake of the BTR model; (2) BTR as a viable model for addressing soaring rental housing demand; (3) tenant-oriented BTR development; and (4) design and construction management of BTR. This research combines these themes into a conceptual framework, provides useful recommendations to facilitate the implementation of BTR developments, and identifies future research directions for this topic. [ABSTRACT FROM AUTHOR]

The study of the mechanical properties between the pile and soil is limited when an enlarged head is added at the bottom of the pile foundation, which acts as anchor stabilization. This study investigates the blade pile foundation used in a solar panel project, which is subjected to lateral wind load action. The parametrical study is performed through the numerical simulation of the blade pile that is embedded in clay soil. The study considers both the soil modulus and the strength parameter of cohesion and concludes that the blade pile foundation capacity has a positive correlation with both. Moreover, when adding blades to a normal circular hollow section (CHS) pile, if the clay cohesion is less than 35 MPa, the capacity improvement rate will be greater. It analyzes the simulated load versus the soil displacement by considering clay in the soil states of very soft, soft, firm, stiff, very stiff and hard. This study finds that the blade application increases the lateral capacity of the pile foundation. In addition, when the soil is very soft to firm, adding blades results in a higher percentage of capacity improvement, which is up to 14.8% for the standard 1.5-m CHS pile with an outside diameter of 76.1 mm. [ABSTRACT FROM AUTHOR]

A bi-directional static load test (BDSLT) is one of the most effective methods for accurately estimating pile bearing capacity, in which the test pile is divided into two portions by activating the single-loading device welded along the pile shaft. BDSLT, thus, eliminates the safety concerns and space limitations imposed by the reaction system, as compared to conventional static load tests (kentledge). Based on this study's project requirements, two loading devices (supercells) were welded along the pile shaft to provide sufficient bearing capacity under the BDSLT, and an equivalent method was applied to interpret the measured load–settlement response. Since the sacrificial loading device welded along the pile shaft cannot be re-used, BDSLTs lead to increased construction costs; however, their capacity for rapid set-up in a limited space and reliable application for long piles are benefits that easily justify their use. Therefore, researchers must understand how BDSLTs perform, especially regarding double-loading devices. As informed by site investigation, this paper validates the conventional analytical solutions regarding test piles in preliminary designs, including Alpha and Beta and semi-empirical methods. In terms of a soil stiffness reduction model, modified closed-form analytical solutions based on Randolph's analytical method were applied to predict the load–settlement response. [ABSTRACT FROM AUTHOR]

This study features the development of a framework to identify drivers towards increasing adoption of modular integrated construction (MiC) methods for affordable sustainable housing (ASH). The rise of offsite construction (OSC) techniques, especially MiC, has been evident in recent years. MiC's adoption in ASH is still underdeveloped; however, due to various benefits of MiC over conventional construction methods, it is envisioned to be a significant emerging approach for tackling growing housing demand, and ASH in particular. Although a few prior studies identified some factors for utilization of MiC towards ASH, studies to date have not provided a holistic review of drivers or a comprehensive framework of the interrelationships between such drivers. To address this issue, this study utilizes a three-way process including a systematic literature review, semi-structured interviews and the Total Interpretive Structure Modelling (TISM) method to study the drivers for MiC adoption in ASH. Initially, 111 drivers were extracted from a review of 40 studies in the existing literature. Following that, the significant drivers of MiC adoption for ASH were grouped into cost, time, productivity, quality, environmental, social, policy and demand. Drawing on concepts of systems thinking and graph theory, the TISM model for eight drivers was developed from both the literature review and the interview results. Four levels of hierarchy were found among drivers containing linkage, driving, depending and autonomous. Succeeding the steps of TISM and Reachability Matrix (RM) and Matrice d' Impacts Croises-Multipication Appliqué a Classement (MICMAC) analysis, social drivers were found to have the highest driving and lowest dependency power, followed by productivity and policy drivers. This signifies the importance of social factors for enhancing MiC adoption for ASH. In addition, a strategic framework of boosting MiC adoption in ASH is also presented, highlighting the key stakeholders and strategies for transformation along with conclusions. This study delivers a wider landscape of drivers for MiC-ASH synergy that may assist practitioners, policy makers and relevant stakeholders to better understand the relationships between the drivers. [ABSTRACT FROM AUTHOR]

As important links in the transport infrastructure system, cable-stayed bridges are among the most popular candidates for implementing structural health monitoring (SHM) technology. The primary aim of SHM for these bridges is to ensure their structural integrity and satisfactory performance by monitoring their behaviour over time. Finite element (FE) model updating is a well-recognised approach for SHM purposes, as an accurate model serves as a baseline reference for damage detection and long-term monitoring efforts. One of the many challenges is the development of the initial FE model that can accurately reflect the dynamic characteristics and the overall behaviour of a bridge. Given the size, slenderness, use of long cables, and high levels of structural redundancy, precise initial models of long-span cable-stayed bridges are desirable to better facilitate the model updating process and to improve the accuracy of the final updated model. To date, very few studies offer in-depth discussions on the modelling approaches for cable-stayed bridges and the methods used for model updating. As such, this article presents the latest advances in finite element modelling and model updating methods that have been widely adopted for cable-stayed bridges, through a critical literature review of existing research work. An overview of current SHM research is presented first, followed by a comprehensive review of finite element modelling of cable-stayed bridges, including modelling approaches of the deck girder and cables. A general overview of model updating methods is then given before reviewing the model updating applications to cable-stayed bridges. Finally, an evaluation of all available methods and assessment for future research outlook are presented to summarise the research achievements and current limitations in this field. [ABSTRACT FROM AUTHOR]

The study aims to develop a reliable model using gene-expression programming (GEP) technique for estimating the unconfined compressive strength (UCS) of soil stabilization by cement and fly ash. The model considered the effects of several parameters, including the fly ash characteristics such as calcium oxide (CaO) content, CaO/SiO2 ratio, and loss of ignition. The research results show that the proposed model demonstrates superior performance with a high correlation coefficient (R > 0.955) and low errors. Therefore, the model could be confidently applied in practice for a variety of fly ash qualities. Besides, the parametric study was conducted to examine the effect of fly ash characteristics on the strength of soil stabilization. The study indicates that if the fly ash contains a high amount of calcium oxide, the strength of fly ash stabilized soil is significant. In addition, fly ash could be used in combination with cement to increase the strength of the mixture. A fly ash replacement ratio is suggested from 0.19 to 0.35, corresponding to the total binder used from 10% to 30%. The research findings could help engineers in optimizing the fly ash proportion and estimating the UCS of soil stabilization by cement and fly ash. [ABSTRACT FROM AUTHOR]

The study of the strength of reconstituted and stabilised soft soils is very important in geotechnical engineering. The soil particles, such as clay, sand, and silt play important roles in determining the behaviour of soils. The behaviour of clay and sand particles are unique; however, the behaviour of silt particles lie in a transitional form between sand and clay. Therefore, this paper seeks to investigate (a) the effect of silt contents on the strength of soft soils; (b) the effect of silt content on the strength of cement-stabilised soft soils; and (c) the microstructure of the soft soil specimens stabilised by cement with varying particle size distribution. A series of tests consisting in consolidated, isotropic undrained (CIU) triaxial tests, unconfined compressive strength (UCS) tests, and scanning electron microscope (SEM) images were conducted in this study to achieve these objectives. In conclusion, the relationship between the silt content and critical state behaviour of soft soils (both clay and silt particles) are proposed. For the cement-stabilised specimens, the unconfined compressive strength increases with the increase in silt content when the cement content is 10%. However, the UCS decreases with the increase in silt content when cement content is 30%. With cement content ranging from 15–25%, the UCS increases at first with the increase of silt content but decreases once the silt content reaches a 'saturation' point. [ABSTRACT FROM AUTHOR]

The extensive application of natural unbound granular materials (UGMs) motivates studies into the mechanical properties of alternatives such as processed crushed rocks employed commonly as base or subbase layers. The rutting and settlement generated in base and subbase layers is widely restricted in many specifications and standards. In this research, the dynamic behavior including the resilient modulus ( M r ) and the plastic strain ( ε p ) of the crushed rocks collected from Queensland in Australia will be tested by a series of repeated load triaxial test (RLT) tests to investigate the behavior of UGMs under the fluctuation of the degree of saturation (DOS) (59%–100%). In particular, the RLT specimens were prepared in the laboratory through proper gradation under optimum moisture content (OMC) and 100% standard proctor maximum dry unit weight. Results from the RLT tests showed that UGM specimens soaked at higher DOS generated lower resilient modulus and weaker resistance to heavy traffic volumes with significant accumulation of plastic strain. The M r and ε p of the tested aggregates under different cyclic deviator stresses of 425 kPa and 625 kPa approximately linearly decreased and approximately linearly increased as the DOS increased with a certain number of cycles up to 50,000, respectively. [ABSTRACT FROM AUTHOR]