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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]

Soil-to-air heat exchanger concept is one of the efficient methods to reduce the cooling effort required for any air conditioning system. In this paper, a theoretical model of soil-to-air heat exchanger has been developed to predict the air temperature in the outlet of the system during a hot atmospheric condition. This theoretical model is used to predict the sub-soil temperature for a specific ambient condition in a southern part of India and also compared with the measured sub-soil temperature. Performance of the soil-to-air heat exchanger system has been calculated during peak hours in summer and found to have the potential to reduce the energy required to cool the building. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new approach to solve the hydro-thermal unit commitment problem using Simulated Annealing embedded Evolutionary Programming approach. The objective of this paper is to find the generation scheduling such that the total operating cost can be minimized, when subjected to a variety of constraints. A utility power system with 11 generating units in India demonstrates the effectiveness of the proposed approach; extensive studies have also been performed for different IEEE test systems consist of 25, 44 and 65 units. Numerical results are shown comparing the cost solutions and computation time obtained by conventional methods. [Copyright &y& Elsevier]

The seismic slope stability analysis of the right abutment of a railway bridge proposed at about 350 m above the ground level, crossing a river and connecting two huge hillocks in the Himalayas, India, is presented in this paper. The rock slopes are composed of highly jointed rock mass and the joint spacing and orientation are varying at different locations. Seismic slope stability analysis of the slope under consideration is carried out using both pseudo-static approach and time response approach as the site is located in seismic zone V as per the earth quake zonation maps of India. Stability of the slope is studied numerically using program FLAC. The results obtained from the pseudo-static analysis are presented in the form of Factor of Safety (FOS) and the results obtained from the time response analysis of the slope are presented in terms of horizontal and vertical displacements along the slope. The results obtained from both the analyses confirmed the global stability of the slope as the FOS in case of pseudo-static analysis is above 1.0 and the displacements observed in case of time response analysis are within the permissible limits. This paper also presents the results obtained from the parametric analysis performed in the case of time response analysis in order to understand the effect of individual parameters on the overall stability of the slope. [ABSTRACT FROM AUTHOR]

• Extensive geotechnical characterization of the soil from landslide slip surface helps evaluate the failure mechanism of landslide. • High-intensity rainfall, unplanned vertical cuts and slopes have witnessed the loss of lives and substantial monetary losses during the southwest monsoon in Kerala, India, in 2018. • Importance of locally available sustainable green martial uses in engineering practices. • The numerical analysis confirmed that the vertical cut stabilization with coir geotextiles is safe during high-intensity rainfall. This paper presents laboratory and numerical analysis of vertical cut failure due to rainfall-induced landslide resulting in building failure that led to the death of nine people in Kerala, India, on August 15, 2018. The residual shear strength parameters are evaluated by the ring shear test. The soil water characteristics curve (SWCC) is developed by unsaturated soil strength parameters. The slope stability and infiltration analysis are carried out with limit equilibrium and finite element methods, respectively. The infiltration analysis is carried out by considering three different rainfall patterns on the slope as low, medium, and high intensities. The study includes a two-stage numerical analysis of vertical cut. Firstly, vertical cut analysis with and without rainfall effects and second, the analysis of vertical cut using coir geotextile as reinforcement with rainfall effects. The study emphasized the utilization of locally available coir geotextiles as a reinforcement for slope stabilization. [ABSTRACT FROM AUTHOR]

Run-of-the-river hydropower projects are developed based on the concept of sustaining reservoir life by sediment management. Sediment management is achieved by sluicing or drawdown flushing through low-level spillways. Simulations with numerical and physical models are essential for optimizing the design and operation of such projects. In this paper, numerical and physical model simulations carried out for sediment management of a run-of-the-river hydropower project are presented. For Devsari Hydroelectric Project, Uttarakhand, India, a physical model was constructed to a geometrically similar scale of 1: 60. Experiments were carried out for sediment management for various scenarios. One-dimensional model Hydrologic Engineering Center's –River Analysis System was used to simulate the longitudinal sedimentation and velocity profiles in the physical model. The numerical model was further applied to the prototype for predicting the long-term sediment deposition along the reservoir stretch. Results of the simulation indicated deltaic sediment deposition in the upstream reaches of the main Pinder and Kailganga rivers. The delta advanced towards downstream for lower reservoir operation levels. The flow velocities in the entire reservoir stretch were observed to be very low, thus confirming the design concept of reservoir functioning as a desilting basin. Experiments were carried out on the physical model for simulating sediment removal by drawdown flushing. It was observed that reservoir capacity can be restored by annual flushing during peak flows. Flushing with discharge of 300 m3/s for 12 h duration can remove about 0.0086 Mm3 of sediment and hence may be adopted for reservoir operation. [ABSTRACT FROM AUTHOR]

Tides play a vital role in coastal hydrodynamics, and it is important to understand their complex characteristics in the coastal areas of creeks, bays, estuaries and gulf. In this study, the spatial variation of heterogeneous friction coefficients and their influence on the variation of different tidal constituents (K1, M2, N2, O1, P1 and S2) along Gulf of Khambhat, west coast of India, were studied. A two-dimensional finite element-based numerical model was developed and zones of different friction coefficients were identified by comparing numerically estimated tidal levels and currents with that of measured and reported by earlier studies. Based on the comparisons, the gulf was divided into five zones of different bottom friction values. The numerical model, assigned with friction coefficients, was used to map the contours of selected tidal constituents. From the results, it was observed that two constituents, M2 and K1, influence the hydrodynamics, significantly. The description of the numerical model, calibration, validation and results are presented in this paper. [ABSTRACT FROM AUTHOR]

This paper deals with the mathematical modeling of the second wave of COVID-19 and verifies the current Omicron variant pandemic data in India. We also we discussed such as uniformly bounded of the system, Equilibrium analysis and basic reproduction number R 0 . We calculated the analytic solutions by HPM (homotopy perturbation method) and used Mathematica 12 software for numerical analysis up to 8th order approximation. It checked the error values of the approximation while the system has residual error, absolute error and h curve initial derivation of square error at up to 8th order approximation. The basic reproduction number ranges between 0.8454 and 2.0317 to form numerical simulation, it helps to identify the whole system fluctuations. Finally, our proposed model validated (from real life data) the highly affected five states of COVID-19 and the Omicron variant. The algorithm guidelines are used for international arrivals, with Omicron variant cases updated by the Union Health Ministry in January 2022. Right now, the third wave is underway in India, and we conclude that it may peak by the end of May 2022. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents valuing of qualitative and quantitative travel attributes influencing the attractiveness of suburban train service in Mumbai city, India. A stated preference experiment is designed to capture the data of sub-urban train mode choice behavior. The behavioral data are analyzed using different modeling techniques such as multinomial logit (MNL) and mixed logit (ML). In ML model, the random parameters are assumed to follow constrained triangular distribution, where mean equals its spread. The decomposition of preference heterogeneity around the mean estimate of random parameter is also investigated using ML model. The study shows the influence of headway time and train ride time associated with a particular crowding level (expressed in density of standing passengers/m2) in choosing the sub-urban train mode by calculating their willingness-to-pay (WTP) values and highlights the importance of WTP for addressing policy issues in the reduction of in-vehicle crowding level. The present study documents new findings of the effect of crowding level on train ride time in the context of a developing country and suggests some important directions for future suburban train transport crowding valuation research. [Copyright &y& Elsevier]

This paper examines an issue concerning the simulation of anomalously wet Indian summer monsoons like 1994 which co-occurred with strong positive Indian Ocean Dipole (IOD) conditions in the tropical Indian Ocean. Contrary to observations it has been noticed that standalone atmospheric general circulation models (AGCM) forced with observed SST boundary condition, consistently depicted a decrease of the summer monsoon rainfall during 1994 over the Indian region. Given the ocean-atmosphere coupling during IOD events, we have examined whether the failure of standalone AGCM simulations in capturing wet Indian monsoons like 1994 can be remedied by including a simple form of coupling that allows the monsoon circulation to dynamically interact with the IOD anomalies. With this view, we have performed a suite of simulations by coupling an AGCM to a slab-ocean model with spatially varying mixed-layer-depth (MLD) specified from observations for the 1994 IOD; as well as four other cases (1983, 1997, 2006, 2007). The specification of spatially varying MLD from observations allows us to constrain the model to observed IOD conditions. It is seen that the inclusion of coupling significantly improves the large-scale circulation response by strengthening the monsoon cross-equatorial flow; leading to precipitation enhancement over the subcontinent and rainfall decrease over south-eastern tropical Indian Ocean-in a manner broadly consistent with observations. A plausible physical mechanism is suggested to explain the monsoonal response in the coupled frame-work. These results warrant the need for improved monsoon simulations with fully coupled models to be able to better capture the observed monsoon interannual variability. [ABSTRACT FROM AUTHOR]

general neural network based methodology that has the potential to replace the computationally-intensive site-specific seismic analysis of structures is proposed in this paper. The basic framework of the methodology consists of a feed forward back propagation neural network algorithm with one hidden layer to represent the seismic potential of a region and soil amplification effects. The methodology is implemented and verified with parameters corresponding to Delhi city in India. For this purpose, strong ground motions are generated at bedrock level for a chosen site in Delhi due to earthquakes considered to originate from the central seismic gap of the Himalayan belt using necessary geological as well as geotechnical data. Surface level ground motions and corresponding site-specific response spectra are obtained by using a one-dimensional equivalent linear wave propagation model. Spectral acceleration values are considered as a target parameter to verify the performance of the methodology. Numerical studies carried out to validate the proposed methodology show that the errors in predicted spectral acceleration values are within acceptable limits for design purposes. The methodology is general in the sense that it can be applied to other seismically vulnerable regions and also can be updated by including more parameters depending on the state-of-the-art in the subject. [ABSTRACT FROM AUTHOR]

Abstract: Towards formulating guidelines for performance evaluation of buildings to site-specific earthquakes, studies are reported in literature on the effect of various critical parameters. No study is, however, reported on the effect of depth of soil stratum. In this paper, a methodology is proposed and applied for performance evaluation of buildings for site-specific earthquakes including depth of soil stratum as a parameter. The methodology integrates independent procedures meant for performance evaluation of buildings and site-specific seismic analysis. Application of the proposed methodology enables to determine performance point of a building in terms of inelastic displacement and base shear. Numerical application of the methodology is demonstrated using the particulars of Delhi region. Two typical RC buildings (B1 and B2) with significantly different inelastic behaviour, assumed to be located on soil depths ranging from 10 to 200m are chosen for the application study. Capacity spectra of the buildings are generated from nonlinear static analysis. Studies indicate that for building B1, with elasto-plastic behaviour, the depth of soil stratum strongly influences demand on inelastic displacement compared to that on inelastic base shear. For building B2, with continuously varying inelastic behaviour, the depth of soil stratum is observed to have significant influence on both the inelastic base shear as well as inelastic displacement. Responses of the buildings are compared with that obtained based on design spectrum of Indian seismic code. For both the cases, inelastic displacements as well as inelastic base shears are underestimated by Indian seismic code for certain depths of soil stratum. Proposed methodology enables the calculation of realistic values of inelastic base shear and corresponding displacement of a building for site-specific earthquakes by considering the actual characteristics of soil stratum. [Copyright &y& Elsevier]

This study quantifies the erosion of the Chennai coast in India and predicts how the shoreline will recede in the future. Previous studies in this region have reported erosion rates varying anywhere from 2 to 8 m/y. Such a high level of inconsistency in reported rates has hindered effective and sustainable coastal management. The research reported in this paper addresses this issue, using mapping data from 1904, 1974, 1996, and 2002 to estimate, by linear regression, the shoreline recession. The 10 km stretch of coast N of the fishing port at Chennai is repeatedly threatened during the NE monsoon, and as the process continues, the existence of a vital road link (the east-coast highway) is challenged by the fury of the waves. It is estimated that 260 ha of land has been lost between 1893 and 1955 and that 30 ha was destroyed by the sea between 1980 and 1989. Overall loss between 1893 and 1989 has been estimated in the order of 350 ha. The cost of land alone lost to the sea is in the order of US$40 million. The N Chennai coast has thus become volatile and is in need of immediate relief measures for the upkeep of the coastal region. Predictions for the next 250 years were then undertaken using a variety of techniques ranging from a process-based numerical model (Soft Cliff And Platform Erosion) to geometric approaches (including historical-trend analysis, the modified Bruun model, and Sunamura's shore platform model. The mean historic rate of erosion in the Chennai region is 1.11 m/y (60.15 m/y), significantly less than previously reported, though still very high. Subsequent predictions were used to identify a series of significant economic, ecological, and social features at risk, and to estimate when they will be lost to erosion if left unprotected. [ABSTRACT FROM AUTHOR]

An extraction method for deep-seated thick seam deposits by underground mining with high resource recovery has remained a great challenge for Indian mining engineers, whereas the longwall top coal caving (LTCC) method has evolved as an effective method for various geo mining conditions in China and other counties. The percentage of top coal recovery (TCR) plays a predominant role in determining the feasibility of LTCC, which relies on the First Top Coal Caving Distance (FTCD). In this paper, the critical geotechnical parameters are identified, numerically simulated, and statistically analyzed, and the FTCD for Indian geo-mining conditions is developed and validated. A financial assessment is conducted, considering 70% top coal recovery at 85% performance level, cost of production escalated by 20% and fall in coal grade by two grades. The internal rate of return (IRR) for LTCC is 30.24% as per the sensitivity analysis where it is only 18% in single pass longwall method. This study contributes to evaluating both the technical and economic feasibility of introducing LTCC in Indian geo-mining conditions. [ABSTRACT FROM AUTHOR]

According to the in situ measured data of the air temperature and ground temperature inside of Kunlun mountain tunnel on Qing–Tibet railway, China, the thawed extent of the permafrost surrounding the tunnel is very large, caused by the latent heat of the cast in situ concrete lining insulation during excavation in winter and other artificial activities. In this paper, taking the coupled effects of moisture transfer and heat conduction into account, a finite element formula of this problem is derived from the governing differential equations with phase change and moisture transfer equations using Galerkin''s solution. Using the computer program, predictions for the refreezing of Kunlun mountain permafrost tunnel are made. The analysis results show that the vault of Kunlun mountain tunnel would have been refrozen by 31 March 2004, the arch bottom by 30 September 2004 and the total tunnel by 30 September 2005, without insulation material. On the other hand, if the tunnel is fitted with insulation material, whose thermal conductivity is equal to 0.03 W/m.K and thickness of 0.05 m, the vault of Kunlun mountain tunnel would have been refrozen by 31 March 2004, the arch bottom by 31 December 2004, the left wall by 31 March 2006, and the right wall by 30 September 2006. Thus, insulation material will delay the refreezing of Kunlun mountain permafrost tunnel. The thawed extent of the permafrost surrounding the tunnel in cold regions caused by construction must be considered, and the time of the field observation should be extended, or observational results, such as their temperature and stress field, will greatly be different from results in stability. [Copyright &y& Elsevier]

• SHM experimental campaign conducted on a multi-arch masonry bridge located in India. • Large longitudinal crack on one of the arches detected with considerable crack width. • SHM monitored with crack growth monitoring and tilting of the spandrels. • Application of two different heavy loads (water tank and hydra crane) located in different positions. • Numerical modelling with advanced full 3D approach with adaptive NURBS FEM in limit analysis. The paper presents some SHM results belonging to a wide experimental campaign conducted on a multi-arch masonry bridge located near Mumbai (India), exhibiting a large longitudinal crack on one of the arches and the corresponding advanced numerical evaluations carried out with a NURBS kinematic limit analysis approach, used to assess the stability of the arch subjected to the passage of heavy traffic loads. The masonry bridge is a three-arch structure built during the mid-19th century by British engineers to connect Bombay with the inland of the Indian subcontinent. At present, it is characterized by a heavy state of degradation especially in one of the arches that requires an immediate evaluation of the safety under the passage of traffic loads and possible ideas of interventions to strengthen the structure, in order to avoid the propagation of deep cracks along the longitudinal direction. The adopted SHM includes the crack growth monitoring and tilting of the spandrels under the application of two different heavy loads (a water tank truck and a hydra crane) located in different positions of the arch. Numerical modelling is carried out with a full 3D approach with NURBS finite elements in limit analysis that takes into account the pre-existing crack opening and predicts with great accuracy the ultimate loads in different scenarios and the corresponding active failure mechanisms. From experimental monitoring and numerical simulations results, it is concluded that the bridge is still safe under the passage of traffic loads, but approaches the ultimate limit state for some specific configurations of the loads applied. A refurbishment is therefore needed to avoid any further propagation of the cracks up to collapse. [ABSTRACT FROM AUTHOR]