Voids behind the lining that develop during long-term operation can seriously compromise the seismic safety performance of metro shield tunnels. To investigate the influence of such void defects on large-diameter shield tunnels, this study systematically analyzed the causes and distribution patterns of voids. A three-dimensional discontinuous finite element model was developed to simulate the interaction among lining segments, connecting bolts, and surrounding rock. The seismic responses, including circumferential stress, interface slip, interface opening, and bolt tensile stress, were analyzed considering coupled factors such as the void circumferential angle, radial depth, distribution location, and geological conditions. Single-factor and multi-factor sensitivity analyses were conducted to evaluate the significance of the above coupled factors on the overall seismic response. The results show that lining circumferential stress, displacement, interface opening, and bolt stress increase with void enlargement, a shift in void location from the crown to the haunch, and deterioration of geological conditions. A void located at the right haunch leads to a peak circumferential stress of 3.27 MPa, causing local segment damage. Sensitivity analysis reveals that void location is the most influential factor affecting the seismic response, while geological conditions exhibit lower sensitivity. A predictive model for the peak circumferential stress around the void was established using multiple linear regression, incorporating void position, circumferential angle, and radial depth. Within the parameter range considered in this study, this model provides a theoretical basis and practical reference for rapid seismic risk assessment and safety management of shield tunnels with void defects.

Historical masonry minarets are highly vulnerable to seismic actions due to their slender geometry, limited tensile capacity, and material heterogeneity. However, their response to near-fault ground motions characterized by velocity pulses remains insufficiently explored. This study investigates the seismic response of the historical Tavanlı Mosque Minaret (1894, Trabzon, Türkiye) subjected to pulse-like (PL) and non-pulse-like (NPL) near-fault ground motions. A three-dimensional finite element model (FEM) was developed in ANSYS Workbench and systematically calibrated using empirical formulations to represent the current dynamic condition of the structure. Seismic performance was evaluated through linear dynamic analyses in terms of displacement demands, principal stress distribution, and drift-ratio-based performance levels. The results indicate that model calibration significantly modifies the dynamic characteristics, increasing the fundamental frequency from 0.734 Hz to 1.126 Hz and reducing displacement demands by approximately 35–76% across the considered records. Despite this improvement, PL ground motions consistently generate more critical deformation demands than NPL motions, frequently exceeding Collapse Prevention (CP) limits even when Peak Ground Acceleration (PGA) values are relatively low. A key finding is that seismic demand cannot be reliably predicted by peak intensity measures or pulse-period ratios (Tp/T1) alone; rather, velocity-related parameters and pulse coherence govern the structural response. These results demonstrate that integrating empirical model calibration with pulse-sensitive seismic analysis is essential for reliable seismic assessment and conservation planning of slender historical masonry structures located in near-fault regions. The study offers a systematic framework that integrates model calibration and pulse-sensitive seismic analysis for evaluating the drift-controlled response of slender historical masonry minarets in near-fault regions.

The growing importance of urban seismic resilience highlights the need for effective strategies to minimize earthquake-induced losses of building groups. Urban seismic capacity assessment requires rapid and accurate prediction of buildings’ seismic responses. However, in large urban building groups, the design information of many buildings is often difficult to obtain completely. In addition, post-earthquake interruption of economic activities will cause significant indirect losses to the city. Based on this background, this paper developed a convolutional neural network (CNN) model using structural characteristic parameters and ground motion parameters, by which the seismic response of structures in a building group can be rapidly predicted. On this basis, the repair priority of buildings was determined according to the repair efficiency value, and an optimal repair strategy considering indirect losses was proposed to minimize the post-earthquake indirect losses of building groups. Taking 908 buildings in Shanghai as an example, the effectiveness of the model is verified, and a comparison is made with the existing conventional repair strategies. Results showed that the proposed neural network accurately predicted the damage states of buildings. Compared with other existing strategies, the proposed optimal repair strategy effectively reduced the indirect economic loss. Further, the increased repair resources can reduce the indirect economic loss and repair time, but the reduction ratio decreases with the further increase of resource allocation.

This study investigates the seismic performance limitations of a newly constructed reinforced concrete building that collapsed during the 6 February 2023 Kahramanmaraş–Elbistan earthquake despite formal compliance with current seismic design requirements. Beyond the specific earthquake event, the study addresses a broader scientific problem: the limited understanding of the relationship between observed damage mechanisms and nonlinear dynamic response in mid-rise reinforced concrete buildings. The first part classifies recurring structural and non-structural damage patterns identified in newly constructed RC residences. The second part presents a nonlinear fiber-based static and dynamic analysis of a collapsed mid-rise building. Nonlinear dynamic analyses were conducted using ground motion records scaled to match the site-specific elastic design spectrum defined by TBDY 2018, corresponding to predefined seismic performance levels rather than an incremental dynamic analysis framework. The results indicate that an extremely low shear wall–to–floor area ratio (0.0357%) combined with asymmetric vertical element distribution significantly amplified torsional response and local shear demands. Nonlinear dynamic analyses showed that critical shear walls exceeded Collapse Prevention limits under DD2-level excitation, while system-level shear contribution limits remained within code-defined thresholds. Dynamic base shear demand corresponded to approximately 30% of the maximum nonlinear capacity obtained from pushover analysis, indicating that localized member failure rather than global strength deficiency governed the collapse mechanism. The analytically identified critical members were consistent with the observed collapse configuration, particularly at the soft ground story. The findings demonstrate that prescriptive code compliance alone may not ensure satisfactory seismic performance when structural irregularities, torsional amplification, and detailing deficiencies coexist. The results are consistent with damage patterns reported in other recent destructive earthquakes and contribute to improving the understanding of collapse mechanisms in code-compliant RC buildings.

Nonlinear energy sink containing phase-transforming cellular materials for vibration control under wind and seismic responses

Multi-task deep transfer learning for complicated seismic dynamic response prediction in slope systems

Sensitivity of seismic pile responses to interface assumptions under SH-wave incidence incorporating the coupling effect between debonding and sliding

Seismic response characteristics of inclined locally liquefied sites: A large-scale shaking table test

A Fully Coupled Flow Deformation Model for Seismic Response Analysis of Underground Structures in Liquefiable Sites

Impact of embedded tunnels on seismic response of saturated sandy ground: Insights from 1 g shaking table tests and CFD-DEM simulations

On modeling the seismic response of spent nuclear fuel assemblies in vertical dry storage casks

Seismic response of pile group foundations in deep saturated sand sites under strong earthquakes

Numerical study on the seismic response of high-rise steel frames with intentionally eccentric braces

3D seismic response and disaster performance of T-shaped intersecting valley fault sites: A case study of a simply supported beam bridge across fault

Identification and analysis of the offshore near-fault pulse ground motion and its influence on the seismic response of bridge piers

Analytical solution for seismic response of deep parallel tunnels under inclined P/SV waves

A composition of simplified physics-based model with neural operator for trajectory-level seismic response predictions of structural systems

Seismic response analysis of automated underground garages based on shaking table test

An approach for assessing seismic response of degrading permafrost sites

Introduction. The construction of civil buildings in permafrost areas is accompanied by risks associated with the formation of a thawing bowl at the base. Materials and methods. Numerical modeling of the "building – foundation – base" system under seismic impacts of various frequency compositions has been performed. Aim. Assessment of the impact of the thawing bowl on the earthquake resistance of civil buildings with various structural systems, taking into account seismic impacts of various frequency compositions. Results. It has been established that the presence of a thawing bowl changes the dynamic behavior of a building depending on its structural system and the frequency characteristics of an earthquake. The most pronounced increase in horizontal displacements is observed for medium–rigid and flexible structural systems in the low- and medium-frequency range, while rigid frameless systems maintain a more stable behavior. Conclusions. The results show that when calculating seismic impacts in permafrost conditions, it is necessary to consider the integral system "building–foundation–base". Taking into account the joint work of the structure and the thawing ground allows for a more accurate assessment of the seismic response of buildings with various structural systems.