@inproceedings{bib_Seis_2026, AUTHOR = {Rajaram, Chenna and Singhal, Shubham and Vemuri, Jaya Prakash }, TITLE = {Seismic assessment of mid-rise buildings on hill slopes under near-fault ground motions: a parametric study}, BOOKTITLE = {innovative Infrastructure Solutions}. YEAR = {2026}}

Buildings on hill slopes have sustained extensive damage during the past seismic events, owing to their distinct dynamic characteristics compared to buildings on flat ground. Structural design codes are short of provisions for design parameters for buildings on hill slopes, which leads to inadequate design practices for such buildings. This study investigates the seismic behavior of buildings on hill slopes with varying slope angles, i.e., 0°, 10°, 20°, and 30°. A typical building plan was selected, which was modelled as three and four storey buildings and analysed in the INSPECT tool. The buildings were subjected to seven near-fault ground motions, and the dynamic response was studied in terms of displacement, damage, time period, and energy ratio. The results underlined the importance of considering slope angle in the design of buildings in hilly regions, particularly for four storey buildings. The findings from the present study indicate an urgent need to formulate seismic design guidelines for buildings on hill slopes, incorporating the influence of lateral displacement, time period, and energy ratio.

@inproceedings{bib_Stud_2026, AUTHOR = {Singhal, Shubham and Tomar, Ravinder Kumar and Tamang, Ashish }, TITLE = {Study of Slope Stability Analysis of Hill Slopes with Retaining Walls}, BOOKTITLE = {International Conference on Trends & Recent Advances in Civil Engineering}. YEAR = {2026}}

This study analyses the slope stability of hills under different heights of retaining walls and slope angles, both with and without water pressure, using the Morgenstern-Price analysis method in GeoStudio software. The slip surface option employed is Entry and Exit, and the slope stability material model is Mohr–Coulomb. The deciding parameter for the analysis is the Factor of Safety. The study finds that when water pressure is considered, the stability of slopes with the same angle and wall height is lower than that of slopes without water pressure. Additionally, as the slope angle increases, the stability of the slope decreases. The study also reveals that a slope that is stable at 30˚ under no water pressure condition becomes unstable when water pressure is considered. Finally, based on the available data and analysis results, the study infers that more than half of the area is considered unsafe since slopes with a gradient of more than 30˚ have a factor of safety of less than one. The findings of this study can be used to design and plan effective slope stabilization measures and land use planning in the region.

@inproceedings{bib_Nume_2025, AUTHOR = {Singhal, Shubham and Chandra, Veligatla Phani and Tiwari, Dhananjay }, TITLE = {Numerical Study on Seismic Performance Evaluation of 3D Printed Concrete Buildings}, BOOKTITLE = {Symposium on One Health, One World}. YEAR = {2025}}

3D printed concrete buildings facilitate a more efficient and sustainable construction process as compared to conventional construction system. However, the seismic behaviour of 3D-printed concrete buildings remains largely unexplored, despite growing interest in sustainable and rapid construction technologies. This study aims to evaluate the seismic performance of a 3D-printed concrete building with 250 mm thick walls and a zigzag in-fill pattern designed to enhance the lateral force resistance. The building model measuring 3 m×3 m in plana and 3 m in height, was developed in Abaqus using a layer-by-layer deposition approach that replicates realistic 3D printing technique with a 50 mm nozzle. Tie constraints and surface interactions were assigned between structural components to simulate bonding and contact conditions after printing. The structure was subjected to lateral loading of varying magnitude. 3D printed concrete building’s performance was studied in terms of stresses and seismic parameters. Lateral load-displacement curves were extracted to quantify the seismic behaviour in terms of lateral load carrying capacity, ductility, stiffness, drift, over-strength factor, response reduction factor, and damage index. This study forms the basis for further research on seismic behaviour of 3D printed concrete buildings, particularly for material and geometrical optimization.

@inproceedings{bib_Seis_2025, AUTHOR = {Singhal, Shubham and Chourasia, Ajay }, TITLE = {Seismic design parameters for precast reinforced concrete structural elements with different joint connection systems under in-plane lateral loading}, BOOKTITLE = {Asian Journal of Civil Engineering.}. YEAR = {2025}}

The robustness of precast concrete structures is primarily governed by connections between the precast structural components. Joint connections deliver a vital role in load transfer, restraining movement, and providing stability at local and global level. This calls for appropriate connection mechanism for precast elements providing integrity under different loading conditions and ease of construction. The connection details in literature or available in practice have been rarely evaluated. This paper discusses the numerical modelling of precast reinforced concrete structural wall-column with different joint connection systems and evaluates various seismic design parameters, simulated through in-plane lateral loading in a finite element software. The connection systems evaluated are reinforcement bar connection, headed bar connections, U-bar connection and steel wire loop connection, which are subsequently compared with a cast-in-situ reinforced concrete wall-column model having similar material and geometrical properties. The seismic behaviour of connections have been studied with regards to the damage pattern, stresses, lateral load capacity, base shear coefficient, stiffness, deformation characteristics, strength factors, and damage index. Among all the connection systems, U-bar connection and loop connection using steel wire ropes showed stresses within the yield limit, while other connection systems reached their yield capacity, indicating damage. Apparently, steel wire loop connection is found to be effective in transfer of lateral load between the precast reinforced concrete elements, as observed from the numerical analysis; whereas other connection systems yielded prior to the design load. However, all connections except the reinforcement bar connection surpassed design load prior to the peak limit.

@inproceedings{bib_Dama_2025, AUTHOR = {Chourasia, Ajay and Singhal, Shubham }, TITLE = {Damage Assessment and Structural Behavior Factor for Precast Reinforced Concrete Structural Systems}, BOOKTITLE = {World Conference on Earthquake Engineering}. YEAR = {2025}}

Design codes and standards provide a range of values for structural behavior factor for precast reinforced concrete (RC) structural systems. However, most of the codes give common value for all kinds of precast RC structural systems, due to the lack of information from experimental studies. Thus, the present paper highlights experimental investigation on behavior of different precast RC structural systems through quasi-static reversed cyclic tests on precast RC systems subjected to displacement-controlled loading. Different precast RC structural systems tested are precast RC wall-column system, precast RC double leaf system and precast RC beam-column joints with different configurations. Damage assessment has been carried out through observations and data obtained from the experiments, which has been co-related with the grade of damage, damage index and deformation capacity. Consequently, structural behavior factor for different precast RC structural systems has been determined. The structural behavior factor thus obtained would be beneficial for practising engineers and structural designers for analysis and design of different precast RC structural systems.