The unwanted vibrations resulting from man-made activities are very common and can cause damage to the surrounding buildings. Previous studies have suggested single barriers for vibration isolation that require unrealistic depth requirements. To effectively control the vibration-related hazards, a geotechnical seismic isolation strategy of dual shallow barriers has been explored in the present work. Geofoam has been used as a filling material in the barriers. Extensive field studies and numerical simulations have been performed to isolate the continuous harmonic vibrations. The Lazan-type mechanical oscillator has been utilized to generate continuous harmonic vibrations of frequencies ranging from 20 to 45 Hz. A comprehensive numerical investigation has been conducted to screen continuous harmonic vibrations. The barriers were found to eliminate vibrations of higher frequency more effectively compared to low-frequency excitations. The isolation efficiency of EPS15-infilled dual barriers of a normalized depth of 0.31 was noticed to be 45% higher than that of the EPS15-infilled single barrier of a similar depth (where EPS is expanded polystyrene). Furthermore, an optimum depth of 0.5 LR for EPS15-infilled dual barriers was noticed to be sufficient to reach the vibration-limiting criteria of isolation efficiency equal to or greater than 75% (where LR is Rayleigh wavelength).

Numerical investigation of high-damping rubber cores to enhance the damping performance of elastomeric seismic isolators

Investigations on vertical and horizontal behavior of a three-dimensional isolation system for seismic isolation and subway-induced vibration control

Noninvasive Methods to Estimate the Mass Eccentricity of Steel-Cored Elastomeric Spheres for Seismic Isolation

Micromechanical analysis of load bearing and seismic isolation of unconnected pile-caisson foundations: A DEM-FDM coupling approach

Design and analysis of a three-dimensional seismic isolation device for small modular reactor building

ABSTRACT Seismic isolation technology can effectively mitigate the impact of earthquakes. New sliding and rolling friction composite isolation bearing combines the advantages of sliding as well as rolling. By adjusting the number of balls and gaskets and modifying the friction coefficient, the system achieves coordinated high energy dissipation. In this study, quasi-static tests were conducted on non-rolling ball, four-rolling balls and five-rolling balls composite bearings, and the effects of the number of gaskets, the effects of loading speed and vertical load on hysteretic properties were investigated. The influence of the number of balls and gaskets on the hysteretic performance of the isolation bearing is examined by finite element software.

The use of seismic base-isolation in Mexican projects has increased in the last decade. Particularly, the technology has been used in several buildings with very different characteristics, located in Mexico City. Before 2023, the Mexico City Building Code (MCBC, 2019) did not include in its Complementary Technical Standard for Seismic Design (CTS-SD 2023) requirements for the analysis, design, review and construction of base-isolated structures. Because of this, international design and evaluation standards, such as ASCE 7, EN 1998 and EN 15129, were widely used. Although these international standards are widely acknowledged for their exceptional quality, they do not consider the unique characteristics of Mexico City, including its soft soil conditions and other local factors. To improve the situation, the committee responsible for updating the CTS-SD elaborated and incorporated a new base-isolation chapter into the 2023 edition of this standard. Chapter 13 explicitly establishes the basis for the use of base-isolation in Mexico City, setting a historical precedent as it is the first legal document in the country that addresses this technology. This paper discusses the particularities of the CTS-SD approach for base-isolation in a city that has soils exhibiting a wide variety of dynamic properties. Among the innovative aspects contained in Chapter 13 in relation to international standards are: 1) The definition of a design objectives matrix that relates the minimum required performance for the different seismic intensity levels relevant to the design; 2) The use, for pre-design purposes, of spectral modal dynamic analyses under the consideration of a segmented spectrum that takes into account the different damping levels associated with the fundamental mode and higher modes of vibration; 3) The requirement to carry out a performance-based evaluation to assess the design of base-isolated structures located in the Transitional and Lake Zones of Mexico City; and 4) Specific recommendations to achieve an adequate contrast of lateral stiffness between the superstructure and the isolation system.

Base isolation is a proven technique that decouples the superstructure from ground motion, thereby enhancing seismic resilience by increasing the fundamental time period and dissipating energy through isolator deformationThis study presents a comparative seismic analysis of a high-rise reinforced concrete (RC) building using different base isolators: Lead Rubber Bearings (LRB) and High Damping Rubber Bearings (HDRB) to evaluate their effectiveness in reducing seismic responses.. In this research, a G+10 storey RC building located in Seismic Zone III with medium soil conditions was modelled and analyzed using SAP2000 software as per IS 1893: 2016 (Part 1). Two analytical models—fixed-base and base-isolated were developed and subjected to nonlinear time history analysis using the Kobe (1995) and Superstition Hills (1987) earthquake records. The study analyzed key seismic parameters such as storey displacement, inter-storey drift, and base shear. Results indicated that both LRB and HDRB systems significantly reduced seismic demands compared to the fixed-base structure. The findings demonstrate that base isolation effectively enhances structural performance under seismic excitation. LRB provided greater flexibility and energy dissipation due to the yielding of its lead core, whereas HDRB offered higher inherent damping and temperature stability. The choice between the two systems depends on design priorities, cost, and environmental considerations. Overall, this study confirms the efficiency of seismic base isolation in improving the safety and sustainability of high-rise buildings in moderate seismic zones.

Friction pendulum bearings (FPBs) can effectively improve the seismic performance of bridges in class II sites. However, for class III and IV sites, using only FPBs under large earthquakes can easily cause significant displacement of the main beam, leading to beam collapse. In order to improve the seismic performance of railway simply supported beam bridges under poor geological conditions, this study proposes a new type of combined seismic isolation device, which extends the vibration period of the bridge through hyperbolic spherical bearings and provides energy dissipation through circular steel dampers. Based on the relevant design parameters of the steel damping and the bearing, their mechanical models are calculated and superimposed to obtain the mechanical model of the combined seismic isolation device, and the model is verified through experiments. Then, a bridge model using this device is established using OpenSees, and the effects of pier height, pier height difference, and far-field long-period seismic motion on pier bottom bending moment and support displacement under class III and IV sites are analyzed. The damage status and indicators of the combined device were provided, and the fragility of the device was analyzed. The results show that under design displacement (300 mm), the hysteresis curves of the combined seismic isolation device are with good consistency in mechanical properties in all directions and strong energy dissipation capacity, and the applicable pier height range of the device is determined under class III and IV sites. This study can provide a reference for the seismic isolation design and practical railway simply supported beam bridges.

This article analyzes innovative technologies and engineering solutions aimed at enhancing the earthquake resistance of buildings and structures. It discusses the advantages of seismic isolation, damping systems and dampers, advanced construction materials, 3D printing, and Building Information Modeling (BIM) in improving structural performance under seismic loads. Drawing on international practice, the article considers the prospects for introducing these technologies and solutions in Uzbekistan and highlights their potential contribution to increasing the resilience and safety of the built environment.

Abstract Although laminated elastomeric bearings are integral components in seismic isolation systems, their elastomeric materials remain susceptible to environmental degradation and temperature-induced aging. Silicone elastomers, with their chemical inertness and long-term environmental resilience, offer a compelling alternative, yet their use in seismic isolation remains largely underexplored. This study experimentally validates the suitability of silicone elastomers as durable substitutes by benchmarking their mechanical performance against well-established standards. Concurrently, the influence of crosslinking agents on mechanical response, and the effect of bearing geometry on shear performance, were systematically evaluated. To these ends, a comprehensive experimental program was conducted: Shore A hardness and uniaxial tensile tests to characterize material stiffness and ductility, and quasi-static shear tests on reduced-scale bearing prototypes to assess shear performance under combined compression and cyclic shear loading. The results demonstrate that the tested silicone formulations satisfy all relevant thresholds for seismic isolation applications. Furthermore, the choice of curing agent modulates the trade-off between stiffness and damping capacity, whereas bearing geometry exhibited negligible influence on the overall shear response. These findings position silicone elastomers as high-performance materials with tunable properties, paving the way for their integration into next-generation earthquake-resilient infrastructure.

Elastomeric materials exhibit complex time-dependent behaviour under mechanical loading, necessitating accurate constitutive models for industrial applications. This study investigates the hyperelastic and viscoelastic responses of two carbon black-filled natural rubber compounds (50 ShA and 60 ShA) through cyclic shear/compression tests and stress relaxation experiments. The Arruda–Boyce model captures equilibrium behaviour, while the Bergström–Boyce model predicts transient viscoelasticity without relying on Prony series. Considering the results obtained it can be concluded that quantitative hysteresis analysis shows 7–26% energy dissipation, dependent on hardness and strain rate. Relaxation rates (10−6–10−7 s−1) inversely correlated with hysteresis, validated by FEM simulations. A deviation of <3.5% between experiments and simulations confirms the model’s robustness for long-term viscoelastic predictions. This framework enables the efficient design of rubber components (e.g., seismic isolators, seals) requiring prolonged durability under load.

ABSTRACT Seismic isolation is widely adopted as an efficient and reliable technique for enhancing the seismic performance of engineering structures. The hybrid testing method, which partitions the seismically isolated structure into a numerical substructure and an experimental substructure (typically the isolation bearings), provides an effective approach for investigating the nonlinear and dynamic characteristics of such systems. Crucially, the substructuring technique allows for economical and efficient large- or full-scale testing. The primary purpose of this review is to provide a comprehensive overview of the application of hybrid testing methodologies specifically to seismically isolated structures. Key hybrid testing techniques employed in this context – namely, pseudo-dynamic substructuring testing (PsD substructuring testing), real-time hybrid test (RTHT), and shaking table hybrid testing (STHT) – are systematically introduced and discussed. Furthermore, the review discusses the challenges associated with implementing these hybrid testings for isolated structures. These include accurate substructure modeling, effective online model updating strategies, and the practical implementation of force–displacement mixed control strategies. Major findings highlight both the capabilities and the current limitations of hybrid testing in capturing the complex behavior of seismic isolation systems under dynamic loading.

To improve the safety and functional retention of masonry structures under moderate to severe earthquakes, a systematic study of the mechanical properties of lead rubber bearings (LRBs) and shaking table tests of seismic isolation masonry models was conducted. Firstly, based on the characteristics of low-rise masonry structure houses and common wall sizes, five small-diameter lead-rubber isolation bearings were designed, and vertical performance and horizontal stiffness tests were carried out. The mechanical performance parameters such as equivalent horizontal stiffness, post-yield stiffness, equivalent damping ratio, and vertical stiffness were obtained. The relationship curve and fitting formula between horizontal displacement, shock absorption coefficient and their influencing factors were calculated. Subsequently, a typical two-story brick structure house without structural columns in a village was selected as the test prototype. A vibration table comparison test with and without seismic isolation layer was designed at a 1:2 scale and full counterweight. Using response spectrum analysis and numerical simulation, three seismic waves were selected for both isolated and non-isolated structures, and sensor placement and loading schemes were designed. Based on the comparison of isolation and non-isolation test phenomena, especially the structural damage of the isolation layer, combined with the dynamic characteristics of white noise sweep frequency, acceleration, displacement, interlayer shear force and interlayer displacement angle, the isolation effect is analyzed and the isolation layer model design is verified. The results show that the vertical compression stiffness of LRB No. 4 is relatively stable, the hysteresis curve is full, the horizontal displacement is less than 60.5 mm, the damping coefficient is less than 0.4, the post-yield stiffness is 149.7 N/mm-167.8 N/mm, and the equivalent horizontal stiffness is 193.9 N/mm-218.65 N/mm. The first two periods of the isolation model are longer and the natural frequency is low, about 25% of the non-isolation model. When the peak acceleration is 0.4 g, the reduction rate of the top layer increases to about 48%, and the reduction rate of the first layer increases to about 40%. The displacement reduction rate of the top floor is about 24% under the action of Tangshan waves, about 36% under the action of Jiangyou waves, and up to 40% under the action of artificial waves. The test results verified the rationality of the low masonry isolation model structure and the isolation effect of lead core rubber bearing(LRB) + Frictionless sliding bearing(FSB).

Abstract In earthquake-prone regions, the rapid post-earthquake evaluation of numerous bridges poses a significant challenge, further exacerbated by infrastructure aging. While monitoring technologies are actively being developed to address this issue, sensor placement and measurement selection remain critical obstacles, as bridges often feature unique design conditions that require generalized analysis methods and exhibit strong nonlinear behavior during earthquakes. Such behavior restricts the applicability of methods relying on linear indicators and typically necessitates direct measurement of earthquake accelerations. This study proposes a method for predicting the seismic response of nonlinear isolation bridges without measured earthquake accelerations, using only a limited number of sensors installed on the bridge (formulated as an output-only joint state–input estimation problem). The approach integrates nonlinear observability analysis of the structure–sensing system with Bayesian state estimation. A case study on a typical seismic isolation bridge demonstrates the applicability and effectiveness of the method. Results show that, when observability conditions and appropriate estimator settings are satisfied, nonlinear structural responses and input seismic accelerations can be reliably reconstructed. The proposed method enhances the cost efficiency of sensing technologies and provides valuable insights for broader practical implementation.

The protection of historic buildings in seismic-prone regions is a critical challenge requiring strategies that balance structural safety with cultural preservation. This study proposes an integrated methodological framework for assessing seismic risk in heritage contexts by combining Geographic Information System (GIS)-based large-scale analyses with detailed Finite Element Method (FEM) simulations. At the urban scale, the framework is applied to more than 70 buildings in the historic center of Bronte (Eastern Sicily, Italy) to evaluate Soil–Structure Interaction (SSI) effects and identify priority areas for mitigation. At a detailed scale, the approach is validated through an in-depth investigation of the San Giovanni Evangelista bell-tower, a representative historic structure within the study area. For this case, sustainable Geotechnical Seismic Isolation (GSI) systems using well-graded Gravel–Rubber Mixtures (wgGRMs) are numerically tested as a low-impact retrofitting strategy. The results demonstrate that combining large-scale mapping with detailed structural modeling provides both broad urban insight and accurate site-specific evaluations, offering a replicable decision-support tool for seismic risk reduction in heritage environments. Additionally, wgGRMs-based GSI system significantly reduces seismic accelerations and drifts, offering a low-impact, sustainable retrofitting solution that reuses waste materials and fully preserves architectural integrity.

Advanced materials are essential for enhancing the resilience, efficiency, and adaptability of civil infrastructure. Yet, the core materials used in civil infrastructure systems today have remained largely unchanged for nearly a century, with fixed properties that limit their ability to realize these capabilities. Mechanical metamaterials offer a path to overcome the inherent constraints of conventional civil infrastructure materials. This perspective explores how mechanical metamaterials can redefine the backbone of civil infrastructure systems at the material level by encoding function in geometry, thereby enabling programmable mechanics and advanced multifunctional responses. Their scope of influence spans buildings, transportation networks, underground structures, offshore platforms, and architectural or interior systems, where thousands of components currently designed with conventional materials can be reimagined using optimized metamaterial counterparts. A mechanical metamaterial approach to civil infrastructure design can enhance structural performance by improving strength-to-density ratios, expanding the design space beyond conventional Ashby plot limits, and supporting applications such as seismic isolation, vibration damping, and lightweight construction. The discussion underscores the potential of mechanical metamaterials to introduce advanced functionalities such as energy harvesting, sensing, and wireless communication within civil infrastructure systems. These capabilities, traditionally associated with electronic devices, can be incorporated directly into structural components to create infrastructure with higher autonomy and adaptability. Multimodal integration with electromagnetic and photonic metamaterials further extends these possibilities by allowing materials to exhibit intrinsic communication, stealth behavior, or visual responsiveness. The perspective concludes with a roadmap outlining key developments and challenges toward a more integrated and responsive metamaterial-driven infrastructure. Within this framework, structurally tuned construction metamaterials can sense their environment, process information, and communicate with surrounding systems, functioning as the brain, eyes, and skin of future civil infrastructure.

The increasing density of urban rail networks has resulted in substantial growth in metro-superstructure building development. These structures face dual engineering demands in high-seismic regions: ensuring occupant comfort by mitigating metro-induced vibrations while maintaining structural safety during seismic events. Traditional isolation bearing systems frequently fail to address both vertical and horizontal excitations simultaneously. To address this limitation, a novel three-dimensional seismic and vibration isolation bearing (3D-SVIB) is developed, exploiting the superelastic properties of shape memory alloy (SMA) materials. The 3D-SVIB incorporates thick laminated natural rubber (LNR) components and SMA wires arranged in a parallel configuration. The LNR module primarily accommodates vertical compression loads, while both components collectively resist horizontal shear forces, thereby achieving decoupled directional responses. Mechanical constitutive models were developed based on comprehensive experimental data, with testing demonstrating that the bearing’s vertical stiffness increases from 1,559 to 2,107 kN/mm under progressive compression loading. Furthermore, the horizontal equivalent stiffness increases from 2.95 to 4.76 kN/mm with increasing shear strain amplitude. The bearing system maintains structural stability under deformation levels reaching 150% and demonstrates superior energy dissipation capabilities. Coupling analysis reveals minimal interaction effects, with stiffness variations maintained below 10.05%, thereby validating the decoupled design philosophy. Additionally, frequency response analysis indicates significant resonance control improvements, with structural period elongation achieving 1.93 times (horizontal) and 5.33 times (vertical) compared to the original fixed-base structure. The -12 dB isolation thresholds are reduced to 1.04 Hz and 2.12 Hz for horizontal and vertical directions, respectively, representing 85% and 82% improvements over baseline structural configurations. Dynamic analyses demonstrate substantial vibration reductions under both excitation types. Metro-induced vertical accelerations decrease by 31.65–34.95% across building floor levels, with insertion loss reaching 10.1 dB. Under seismic loading conditions, the 3D-SVIB system limits top-floor displacement to 20.3% of fixed-base response levels, compared to 76.7% achieved by conventional isolation systems. Moreover, maximum interstory displacement ratios are reduced to 61.1% of non-isolated values. Engineering validation through a comprehensive Chongqing transit-oriented development (TOD) project confirms the system’s practical effectiveness for metro-superstructure applications in seismically active regions.

Due to their long wavelengths and low attenuation characteristics, seismic waves pose serious threats to engineering structures, resulting in an urgent need to develop effective vibration mitigation strategies. Locally resonant phononic crystals provide a novel approach to controlling seismic wave propagation, while auxetic materials have attracted considerable attention for their excellent energy absorption capabilities. To achieve broadband low-frequency seismic isolation, this study proposes a seismic metamaterial composed of embedded dual resonators combined with auxetic materials. The bandgap characteristics of the structure are calculated using the finite element method, and the mechanism of bandgap formation is elucidated through vibrational mode analysis. A parametric study is conducted to investigate the influence of mass block substitution on bandgap tunability, and complex band analysis is employed to evaluate seismic wave attenuation within the bandgap range. Furthermore, a graded composite structure is designed, and its seismic isolation performance is validated through frequency- and time-domain simulations. The results show that the proposed composite structure exhibits significant isolation effects within the 2.7-5 Hz bandgap range. Even under excitation with the Chi-Chi earthquake, whose dominant frequency lies outside the bandgap, the peak ground acceleration is reduced by approximately 42%, and the overall acceleration response is effectively suppressed. These findings provide a promising new design strategy for achieving broadband and low-frequency seismic protection in engineering applications.