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The purpose of this study is to numerically model the rigid pavement resting on Pasternak soil and to examine its various response parameters and stress resultants like deflection, rotation, bending moment and shear force when subjected to aircraft loading.

The study is carried out using a one-dimensional (1D) beam element based on the finite element method (FEM). Each node in this element has three rotational and three translational degrees of freedom (DOF). MATLAB programming is used to perform the static analysis of rigid pavement.

Response parameters and stress resultants of the rigid pavement were determined. The FEM used in this work is validated by two closed-form numerical examples, which are in great accord with previous research findings with a maximum divergence of 4.64%, therefore verifying the finite element approach used in the current study. Additionally, various parametric studies have been carried out to study the variations in response parameters and stress resultants.

The investigation at hand focuses exclusively on the static analysis of the pavement. The study constraints pertaining to the preliminary design phase of rigid pavements are such that a comprehensive three-dimensional finite element analysis is deemed unnecessary.

As limited previous research had performed the static analysis of rigid pavement on Pasternak foundation with 6 DOF. Furthermore, no prior study has done seven separate parametric investigations on the static analysis of rigid pavement.

The fundamental period of the structure plays an important role in the seismic analysis. This study aims to analyze the modal response of dam, the two-dimensional (2D) FEM model is developed by using ANSYS 2022 R1 software.

To examine the optimized mesh size to achieve grid independence, the variable element size has been considered, and its optimal value is calculated using the technique of response surface optimization. Further, the effect of damping ratios of 5%, 8% and 10% is also considered for the free vibration analysis of the dam structure.

The results show that the natural frequencies of the dam decrease with a reduction in stiffness of the whole structure. Further, the effect of pre-stress conditions is analyzed and the study has proved that the natural frequency increases after considering the pre-stress as initial condition during modal analysis. Further, it is found that the damping has a substantial effect on frequency for higher modes of vibrations.

The study only focused on modal analysis of the gravity dam, and this study’s results can be used further to evaluate the dynamic behavior of the dam including hydrodynamic conditions.

The finite element tool is used to evaluate the modal response of gravity dam incorporating pre-stress and damping ratio along with soil–structure interaction. Moreover, to the best of the authors’ knowledge, no earlier study has been conducted to evaluate the effect of damping and pre-stress conditions on the stability and natural frequency of the system.

Construction waste reduction (CWR) plays a vital role in achieving sustainability in construction. A good CWR practice can result in optimizing material usage, conserving natural resources, limiting environmental pollution, protecting the environment and enhancing human health. In this regard, the purpose of the current study is to identify the most relevant organizational policies that aid in waste reduction and concurrently explores the congruent measures to be adopted during the construction process in the Indian high-rise building sector.

The research findings were obtained through a mixed- method approach. Content analysis was used to identify waste reduction measures (variables) targeting on the two domains of construction – “waste-efficient execution” and “waste – mitigating organizational policies.” Furthermore, the authors explored and documented the key measures from the identified waste reduction measures using the constraint value of the relative importance index. As the next step, the study listed the theoretical hypothesis based on expert interviews and tested the theory through confirmatory factor analysis.

The results revealed that “waste sensitive construction techniques and strategies” as the most significant category under the domain “Execution” with a path coefficient of 0.85. Concurrently, the study has also determined that “control procedures for budget, quality and resources” as the most effective organizational approach in reducing construction waste in the Indian building industry, with a path coefficient of 0.83.

The current research is context-sensitive to the Indian construction sector. It presents the stakeholder’s perspective on construction waste reduction and the relevant measures to be implemented to reduce construction waste in high-rise building projects in India. It can also act as a concordance for decision-makers to further focus on CWR management and aid in formulating policies suitable for the Indian context.

The issue of evaluating the dynamic characteristics of a bridge due to the presence of rapidly moving vehicles has considerable importance. This study aims to conduct a comprehensive study on the variables that influence the dynamic behavior of a thin-walled box-girder bridge exposed to high-speed train loads using regression analysis.

The high-speed train is mathematically represented by a system with 38 degrees of freedom (DOF), while the sub-track system uses China’s Railway Track System slab track. The numerical modeling of the bridge is accomplished using computationally efficient finite elements that represent thin-walled box-beams. The rail’s imperfections are also accounted for, and they are represented using a power spectral density function. The dynamic response of the bridge is calculated using the Newmark-beta technique, considering several DOFs and stress resultants.

A thorough parametric analysis of the factors affecting the dynamic response of the bridge is conducted and a regression model has been proposed. The regression equation yields an excellent fit for shear force, distortional moment and distortional bimoment, with an R² value near 1. It has also been observed that the range of the coefficient R² in case of bending moment, torsion, torsional bimoment and vertical deflection typically falls between 0.82 and 0.9. R² value near to 1 indicates that it is quite accurate in forecasting the dynamic influence of high-speed trains on the bridge’s response.

The originality of this research lies in pioneering the regression modeling of dynamic responses in thin-walled box-girder bridges and uniquely modeling high-speed trains with 38 DOF, which has not been previously explored in existing studies.