Journal of Structural Technology (e-ISSN: 2581-950X) (p-ISSN: 3049-3382)

A Review on the Effectiveness of Base Isolation Systems in Improving Seismic Performance of RCC Structures

Yuvraj Singh Solanki, Rupali Goud — Tue, 17 Mar 2026 00:00:00 +0000

Reinforced concrete buildings designed with conventional fixed-base assumptions often experience considerable seismic forces, leading to structural and non-structural damage during strong earthquakes. To address this issue, base isolation has been developed as an advanced seismic control technique that aims to reduce the direct transmission of ground motion to the superstructure and thereby minimize seismic demand. This review paper critically examines and synthesizes research studies that investigate the seismic performance of base-isolated RCC buildings in comparison with traditional fixed-base structures. The review emphasizes key seismic response indicators such as base shear, lateral displacement, inter-storey drift, floor acceleration, natural time period, and overall energy dissipation characteristics. Various analytical methodologies employed by researchers, including response spectrum analysis and nonlinear time history analysis, are thoroughly evaluated to understand their effectiveness in capturing the dynamic behaviour of isolated systems. Particular attention is given to the performance of lead rubber bearing isolators, which are widely adopted due to their combined flexibility and damping capabilities. The collective findings of the reviewed literature demonstrate that base-isolated RCC buildings generally show a notable reduction in seismic forces and structural damage when compared to fixed-base buildings, while improving displacement control and occupant safety. Nevertheless, the effectiveness of base isolation depends on appropriate design, site conditions, and seismic characteristics. This review outlines significant findings concerning the advantages and limitations of base isolation systems, thereby providing a comprehensive understanding of their role in seismic risk mitigation.

Dynamic Behaviour of Re-entrant Corner Buildings Considering Soil-structure Interaction

Mukesh Deshmukh, Vaibhav Singh, Rupali Goud — Thu, 19 Feb 2026 00:00:00 +0000

Re-entrant corner buildings, widely used in contemporary architectural design, possess inherent torsional irregularities that make them particularly susceptible to seismic forces. When soil-structure interaction (SSI) is introduced, the seismic behaviour of these buildings becomes even more complex due to the combined effects of soil flexibility and plan discontinuity. This study examines the influence of SSI on the dynamic behaviour of re-entrant corner buildings by analysing their seismic response across varying geometric configurations. A comprehensive literature review was carried out to understand existing research on torsional irregularities, SSI, and seismic performance, revealing a significant lack of studies that integrate re-entrant corner severity with soil flexibility. Building frames with an A/L ratio of 0.8 are modelled as per IS 1893:2016 under both fixed-base and SSI conditions. The response spectrum method was employed to evaluate critical seismic response parameters, including the fundamental time period, storey stiffness, storey shear, and lateral displacement. The findings indicate that SSI considerably alters the seismic behaviour of all building configurations by increasing structural flexibility, amplifying lateral deformation, and reducing overall stiffness. These adverse effects intensify as the A/L ratio decreases, indicating that slender re-entrant corner buildings experience the greatest deterioration in seismic performance under SSI conditions. The study underscores the necessity for enhanced lateral load-resisting systems in such buildings to ensure safe and reliable behaviour during seismic events.

Seismic Irregularity Evaluation of Reinforced Concrete Buildings Based on BNBC 2020

Md. Zahidul Islam, Md. Sohan Mollah, Imam Uddin Ahmad — Thu, 19 Mar 2026 00:00:00 +0000

The seismic performance of reinforced concrete buildings is strongly influenced by structural irregularities, which may amplify demand and lead to undesirable damage patterns during earthquakes. This study presents a code-based evaluation of seismic irregularities in five multi-storey reinforced concrete residential buildings designed according to the Bangladesh National Building Code (BNBC) 2020. Numerical models of the selected buildings were developed using ETABS, and seismic irregularities were assessed in terms of torsional irregularity, soft storey irregularity, mass irregularity, vertical geometric irregularity, and vertical discontinuity, following BNBC-defined criteria. The results indicate that torsional irregularity is the most critical and frequently observed form of irregularity among the studied configurations. Out of five buildings, four exhibited torsional irregularity, with two cases showing extreme torsional behaviour where the torsional irregularity ratio exceeded the BNBC limit by a significant margin, reaching values close to 1.9 at lower storeys. Soft storey irregularity was identified in one building, primarily at the ground floor, due to a substantial reduction in lateral stiffness compared to the upper storeys. No mass irregularity, vertical geometric irregularity, or vertical discontinuity was detected in any of the analysed cases. The findings highlight the sensitivity of torsional response to plan configuration and stiffness distribution, even when buildings comply with basic code requirements. This study emphasises the necessity of early-stage irregularity checks in seismic design to ensure safer and more resilient reinforced concrete buildings in seismic regions.

Non-destructive Restoration Technique for Conservation of Marble and Concrete Structures

A. Chaudhuri, S. Bhattacharyya — Thu, 26 Feb 2026 00:00:00 +0000

A considerable proportion of the world’s contemporary and ancient buildings and structures experience biological degradation and assault over time, which eventually causes an accelerated loss of their distinctive, long-lasting, and aesthetically pleasing qualities. Nowadays, ultraviolet light is employed as a non-destructive technique to preserve building materials. This study’s goal is to use ultraviolet radiation (UVC) to stop fungal biodeterioration of marble and concrete blocks. To do this, pure cultures of Aspergillus sp. obtained from fungal-infected walls (4 cm² surface area) were injected into marble blocks (5 cm × 5 cm × 5 cm) and concrete blocks (10 cm × 10 cm × 10 cm) at a height of two meters above ground. The findings demonstrated that, in comparison to biodeteriorated cubes, marble blocks lost 2.05% of their compressive strength after 180 days, whereas UVC-exposed cubes showed relatively minimal weight loss. Compared to the marble and concrete cubes exposed to UVC, the scanning electron microscope (SEM) pictures clearly showed a significant shift in the surface degradation and fungal colonization of the biodeteriorated cubes. The effectiveness of reducing these noticeable visual and physical alterations of concrete and marble materials against the development of Aspergillus sp. was shown by the application of specific ultraviolet radiation (UVC).

Physics-informed Neural Networks for Structural Dynamics and Vibration Analysis: A Comprehensive Review

Hatim Sanawadwala, Avinash Mishra, Ankit Pal — Thu, 29 Jan 2026 00:00:00 +0000

Physics-informed neural networks (PINNs) have undergone a rapid and transformative evolution between 2021 and 2025, emerging as powerful mesh-free alternatives to traditional numerical solvers for structural dynamics. Conventional approaches—finite element, finite difference, and boundary element methods—struggle with high-order PDEs, extreme stiffness, geometric and material nonlinearities, long-duration transient analyses, and ill-posed inverse problems arising from sparse or noisy measurements. This review consolidates more than 50 recent contributions demonstrating how modern PINN architectures directly address these limitations through auxiliary-variable formulations, separable space-time decompositions, causal and structure-preserving training, hierarchical/adaptive weighting, Runge-Kutta-based temporal embeddings, and hybrid physics-data-driven frameworks. Across benchmark beam, plate, cable, truss, instability, SHM, and multiphysics problems, advanced PINNs consistently achieve displacement and stress errors below 10⁻³–10⁻⁴ for linear systems and 0.5–2% for nonlinear or post-buckling regimes, while delivering computational speedups of 10²–10⁶ over conventional time-marching schemes. Emerging PINN variants further enable robust identification of distributed stiffness, damping, ductility, nonlinear boundary behavior, and unknown excitation using minimal instrumentation—paving the way for real-time digital twins and structural health monitoring. The review highlights how operator-learning extensions (e.g., Fourier Neural Operators, Kolmogorov-Arnold Networks) and hybrid PINN-FEM strategies are overcoming remaining challenges in long-time stability and 3D scalability. Overall, the period 2021–2025 marks a decisive transition wherein PINNs have matured into high-performance, physics-consistent computational engines capable of solving forward, inverse, and multiphysics structural dynamics problems with remarkable accuracy, efficiency, and interpretability.