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Under the shadow of the far-field effect of the India-Eurasia collision, the Tianshan orogenic belt underwent tectonic re-activation in the Cenozoic, accompanied by strong tectonic deformation and frequent large earthquakes. Bounded by two rigid cratonic blocks located in its north and south, a series of marginal foreland fold-and-thrust belts are developed within the Tianshan orogenic belt and continue to develop to the bilateral pull-apart basins. Meanwhile, the faults in the orogenic belt are reactivated. The deformation caused by thrust-related structure accounts for larger than 50% of the total convergence of the Tianshan Mountains, which results in the most active structure with large earthquakes in the Tianshan area. Therefore, it is of great significance to study the dynamic process of the newly generated and reactivated thrust-nappe structures in Tianshan orogen via numerical modeling. This paper selects a classical cross-section profile in the western segment of the Southwest Tianshan Mountains, which contains the Kalpin-Maidan-Nalati-Kemin fault system from the south to the north. We attempt to establish a two-dimensional plane strain, viscoelastic finite element model, by treating the regional faults as a whole fault system and considering the topography, fault geometry, and GPS data. The displacement and stress fields of the model are retrieved, the short-term cumulative deformation field of the overall fault system is analyzed, and the rate of Coulomb failure stress change of each fault is also considered. The results show that the deformation is concentrated in the middle and southern parts of the Southwest Tianshan Mountains. In contrast, the deformation of the Kemin fault in the north is relatively small. According to the Coulomb failure stress changes of these four faults and the historical earthquake catalog, the potential seismicity of each fault is qualitatively analyzed. Our preliminary results suggest that the possibility of large earthquake occurrence is higher in the Kalpin fault, Maidan fault, and Nalati fault but lower in the Kemin fault in the near future. [ABSTRACT FROM AUTHOR]

In slope stability analysis, identification of the mechanism behind slope failure is the key factor during the study. Rock mass characterization and kinematics analysis, like geotechnical investigation methods, are not infallible all the time for the weathered slopes. The presence of different grades of weathered mass on the slope profile acts independently to influence the overall failure pattern. Numerical analysis by finite element method (FEM) is evolved as a primary slope stability analysis tool by overcoming the limitations of the stratified weathered materials on the slope. The paper focuses on the stability analysis of railway-cut laterite slopes of the Eastern Ghats of India. The medium to high-grade metamorphism, followed by physio-chemical weathering, favours the region for more prone to failure. The Force Equilibrium Model and Moment Equilibrium Model have been considered to determine the possibility of independent failure events for the probability analysis. Monte Carlo's probability simulation method has delivered a better result for the weathered slopes by taking many variables for the studied region. A compression study has been made between the outcomes of slope stability analysis methods and the probability analysis models, which provides a comprehensive list of factors to understand the failure mechanism of weathered slopes. [ABSTRACT FROM AUTHOR]

Low volume roads in India mainly comprise of unbound granular materials laid over subgrade with thin bituminous surfacing. Hence, properties of the granular materials play a significant role in the performance of these pavements, as the thin surfacing layer is considered to be a non-structural layer. Therefore, accurate modeling of the granular layers is essential in the evaluation of critical pavement responses. Under application of load, unbound materials exhibit stress dependent characteristics. Thus, consideration of non-linearity in these layers is necessary for accurate estimation of the pavement responses of a flexible pavement structure. The granular materials show stress hardening characteristics, which indicates that the resilient modulus of the material increases with an increase in bulk stress. Finite element codes can be suitably used to handle the nonlinearity of unbound granular layers. Using a three dimensional (3D) finite element (FE) model, this paper examines the effect of nonlinearity in granular layers of critical pavement responses of a low volume road. [ABSTRACT FROM AUTHOR]

The objective of this paper is to estimate permanent displacements of Tehri dam due to an earthquake of magnitude M w = 8·5, the occurrence of which has a high probability in the region, and for an earthquake of magnitude M w = 7·0, for which the dam has been currently designed. A two-dimensional finite element analysis and five different semi-empirical and empirical methods, like, Seed and Makdisi’s method, Newmark’s double integration method, Jansen’s method, Swaisgood’s method and Bureau’s method have been utilized to study the probable dynamic behaviour of the dam and their results are compared to get a range of values within which, the permanent displacement of the dam, is estimated to lie. The present study shows that the predicted displacements due to an earthquake of magnitude Mw = 7·0 are significant but not enough to compromise the safety of the dam. However, the displacements predicted for an earthquake of magnitude Mw = 8·5 are quite high and might cause rupture of filter zones. The maximum deformations (755 cm for Mw = 8·5 and 43 cm for Mw = 7·0) are predicted by Seed and Makdisi’s method while the minimum deformations (14 cm for Mw = 8·5 and 2·5 cm for Mw = 7·0) are computed by Jansen’s method. [ABSTRACT FROM AUTHOR]