High Seismic Intensity Research Articles

Seismic Vibration Control and Multi-Objective Optimization of Transmission Tower with Tuned Mass Damper Under Near-Fault Pulse-like Ground Motions

Although the wind load is usually adopted as the governing lateral load in the design of transmission towers, many tall transmission towers may be damaged or even collapse in high seismic intensity areas, especially under near-fault pulse-like ground motions. To study the seismic vibration control effect of a tuned mass damper (TMD) attached to transmission tower, parametric analyses are conducted in SAP2000 through CSI OAPI programming, including TMD parameters such as the mass ratio μ from 0.5% to 10%, the frequency ratio f from 0.7 to 1.2, and the damping ratio ξ from 0.01 to 0.2. Based on the obtained analysis results, artificial neural network (ANN) is trained to predict the vibration reduction ratios of peak responses and the corresponding vibration reduction cost. Finally, the NSGA-III algorithm is adopted to perform the multi-objective optimization of a transmission tower equipped with TMD. Results show that the vibration reduction ratios first increase and then decrease with the increase of frequency ratio, but first increase and then remain stable with the increase of mass ratio and damping ratio. In addition, ANN fitting can accurately predict the nonlinear relationship between TMD parameters and objective functions. Through multi-objective optimization with the NSGA-III algorithm, TMD can simultaneously and significantly reduce different peak responses of transmission towers under near-fault pulse-like ground motions in a cost-effective manner.

Seismic nonlinear interaction and uplifting effects between the nuclear island building and soil

Since the Fukushima nuclear accident, seismic design requirements have increased, necessitating a more refined evaluation of base uplift for weakly anchored nuclear island buildings. The elevated cooling water over 3000 t is a distinguishing feature of third-generation reactor buildings (RBs). To assess potential safety-adverse coupling effects, seismic wave propagation process through viscoelastic soils, discontinuous interfaces, and sloshing water was analysed. To facilitate nonlinear systematic simulation and parametric study, the traditional soil-structure interaction direct methods are improved and programmed on: thickness-independent viscous-spring elements for stable static-dynamic boundary transitions; seismic forces separated from the artificial boundary for flexible mesh planning; elevated water simulated with gravity stacking and hydrodynamic action. A nuclear island region encompassing water-cooled RBs and underlying soil cushion layer was investigated as a typical scenario to reveal rules using the proposed high-precision simulation platform. Non-negligible structural risks and correlations between multiple factors were quantitatively elucidated according to simulation findings. A time-lagged increase in the base overturning moment may occur because of water oscillations. As the water level increases to 85 %, the uplift height increases, adversely affecting the in-structure response spectra. Earthquake-induced intense uplift may lead to an increase in hydrodynamic pressure along the inner wall. The research results support the practical assessment of buildings with water cooling facilities located in soft composite sites with high seismic intensities.

Experimental study and seismic assessment on base isolated precast concrete frame structure with box connectors

The precast construction method offers fast and environmentally friendly solutions for sustainable development in construction. Various connection methods, including wet and dry, have been proposed to enhance assembly convenience. However, challenges remain in achieving complete assembly and considering disassembly processes, hindering post-earthquake restoration. This study introduces a precast RC structure system with easily assembled joints that facilitate disassembly. To enhance the structural system's adaptability to regions with high seismic intensity, rubber-bearing base isolation technology is employed to optimize its seismic performance. Shaking table tests were conducted to evaluate the structure system's dynamic response and seismic performance. Test results indicate that the isolation layer significantly decreases the acceleration response, inter-story drift ratios, floor shear forces, and strain of reinforcements. The isolation structure has a high probability of entering operational and immediate occupancy states during rare earthquakes. The deformation of the isolation bearings has a decisive impact on the overall seismic fragility of the isolation structure system.

Economic impact of large earthquakes: lessons from residential property values

Abstract Understanding how economic agents respond to seismic shocks in a developing country setting is crucial to evaluating the economic costs of natural disasters. This article makes use of the quasi-random spatial and temporal nature of ground tremors to estimate the economic impact of the April 2015 earthquake on residential property values in Nepal. Regression estimates from the difference-in-differences research design show that residential property values declined by about 40.52 percentage points in areas with high seismic intensity. The event study model illustrates that these negative economic effects are more pronounced between 12 and 24 months after the incidence of the earthquake. Findings further underscore the underlying mechanism of physical damage and indicate that residential properties with weaker outer walls, foundations and roof materials became more susceptible to the earthquake.

Seismic Vulnerability Assessment of Non-Overflow Concrete Gravity Dam Section

Abstract As the economy advances, there is a growing need for energy. Harnessing hydroelectric energy has emerged as a crucial strategy for addressing the energy crisis. To promote hydropower development, numerous tall concrete dams are either under construction or in the planning stages. These dams are frequently situated in areas with elevated water levels and face the challenge of being located in regions with high seismic intensity. An accident resulting from the failure of concrete dams can pose significant threats to both economic development and public safety. Therefore, it is of crucial importance to investigate the stability of such dams, particularly under conditions of high water levels and seismic activity. The finite element program Geostudio is being undertaken to evaluate a complete numerical analysis of the dam. In this paper, Longtan Dam has been selected as the case study for the research. This study is applied in two cases: seismic and static conditions. A two-dimensional seismic numerical analysis was carried out using the Koyna earthquake acceleration time records in 1976. The results of the FEM model concluded that the dam is unsafe under sesmic conditions. The concrete-rock interface, particularly susceptible to sliding, was identified as the most critical part of the dam, presenting the most likely failure mode. The study highlights the significance of its methodology in investigating earthquake effects on dams, prioritizing it over the achieved results. The aim is for the conclusions and recommendations to provide valuable guidance for future studies and initiatives focused on enhancing safety at hydropower dams.

The movement pattern changes of population following a disaster: Example of the Aegean Sea earthquake of October 2020

Unexpected seismic events can have a significant impact on our daily lives. Examining post-disaster population movement patterns contributes to disaster response and recovery operations. While most studies analyze population movement or displacement data, only a few examine multi-level movement patterns and consider public transportation demand. This paper aims to analyze changes in movement patterns following a major earthquake that severely affected İzmir in Türkiye, mainly using movement data from the Data for Good platform of Meta. According to the findings, on the first day following the earthquake, those traveling within İzmir considered the areas least damaged to be safer, despite the higher seismic intensity. The timeframe alignment between aftershock activity and the number of people traveling within İzmir suggests the routine movement pattern within the city was regained as the aftershocks decreased day by day. Unlike intra-city travel routines, there was an increase in the number of people moving to summer houses, located far from the center of İzmir. By November 2, 2020, three days after the earthquake, intra-city movements reached a new normal, as confirmed by public transportation use. However, intra-city travel patterns were impacted for approximately one month. This study reveals key findings from the evaluation of post-earthquake movements to improve disaster management decision making and aid crisis response and recovery operations.

Nonlinear modeling and time-history analysis of dry-assembled precast concrete frames with buckling-restrained braces

A combination of dry-assembled precast concrete frames and buckling-restrained braces (BRB) is a viable choice for achieving the full potential of building industrialization and promoting the popularization of precast structures in earthquake-prone zones. A recent study has tested the seismic performances of a dry-assembled precast concrete frame with BRBs (BRB-DPCFs) under cyclic quasi-static loading. To study the comparative seismic behaviors of BRB-DPCFs and the monolithic concrete frames with BRBs (BRB-MCFs) under ground motion records, buildings between 3 and 12 stories in height were designed based on GB50010-2016, Chinese code for design of concrete structures, and investigated numerically. This investigation includes two-dimensional nonlinear time-history analyses of BRB-MCFs and BRB-DPCFs under two seismic hazard levels. BRB-DPCF demonstrated a larger maximum story drift compared to BRB-MCF, while the maximum residual story drift of the former is negligible in comparison to the latter at a higher building height or under a higher seismic intensity. The two systems show similar drift concentration factors, which was observed irrespective of the hazard level and the specific height of the building.

Seismic Performance of a Single-Story Timber-Framed Masonry Structure Strengthened with Fiber-Reinforced Cement Mortar.

Timber-framed masonry structures are widely used around the world, and their seismic performance is generally poor. Most of them have not been seismically strengthened. In areas with high seismic fortification intensity, there are great potential safety hazards. And it is urgent to carry out effective seismic reinforcement. However, due to the complicated construction process of the existing reinforcement technology, the poor durability of the reinforcement materials, and the significant disturbance to the life of the original residents, an efficient single-story timber-framed masonry structure reinforcement technology suitable for comprehensive promotion and application has not been explored. In this paper, a fiber-reinforced cement mortar (FRCM) material was proposed. A 1/2 scale model of a single-story timber-framed masonry structure was taken as the research object. The method of strengthening a single-story timber-framed masonry structure with FRCM layer was adopted. And the shaking table test of the model before and after reinforcement was carried out in turn. The dynamic characteristics, failure modes, acceleration response and displacement response of the FRCM layer-strengthened structure were analyzed through comparisons of the two cases. The experimental results showed that the FRCM layer significantly improved the seismic performance of the seismic-damaged single-story timber-framed masonry structures. The X- and Y-direction natural frequencies of the model structure were increased by 31.30% and 30.22%, respectively, after the structure was strengthened with FRCM. During a rare eight-degree earthquake, the inter-story displacement angles in the X- and Y-direction of the unreinforced model reached 1/98 and 1/577, respectively, and the structure was destroyed, while the inter-story displacement angle of the FRCM-reinforced model was only 1/2 of that the unreinforced model. During a rare nine-degree earthquake, the X-direction inter-story displacement angle of the model strengthened with FRCM reached 1/78 and the Y-direction inter-story displacement angle reached 1/178. At this time, the reinforced model structure was destroyed, but there was no collapse of the structural components, which met the seismic design objectives of "operational under the design minor seismic intensity, repairable damage under the design seismic precautionary intensity, and collapse prevention under the design rare seismic intensity", which proved that the FRCM layer was an effective and feasible way to strengthen the existing single-story wood-masonry rural building.

Study on seismic fragility of prefabricated columns connected by grouted sleeves based on IDA method

PurposePrefabricated columns connected by grouted sleeves are increasingly used in practical projects. However, seismic fragility analyses of such structures are rarely conducted. Seismic fragility analysis has an important role in seismic hazard evaluation. In this paper, the seismic fragility of sleeve connected prefabricated column is analyzed.Design/methodology/approachA model for predicting the seismic demand on sleeve connected prefabricated columns has been created by incorporating engineering demand parameters (EDP) and probabilities of seismic failure. The incremental dynamics analysis (IDA) curve clusters of this type of column were obtained using finite element analysis. The seismic fragility curve is obtained by regression of Exponential and Logical Function Model.FindingsThe IDA curve cluster gradually increased the dispersion after a peak ground acceleration (PGA) of 0.3 g was reached. For both columns, the relative displacement of the top of the column significantly changed after reaching 50 mm. The seismic fragility of the prefabricated column with the sleeve placed in the cap (SPCA) was inadequate.Originality/valueThe sleeve was placed in the column to overcome the seismic fragility of prefabricated columns effectively. In practical engineering, it is advisable to utilize these columns in regions susceptible to earthquakes and characterized by high seismic intensity levels in order to mitigate the risk of structural damage resulting from ground motion.

Energy dissipation and seismic response reduction system for high-speed railway bridges based on multiple performance requirements

The emergence of high-speed railway bridges in regions with high seismic intensity has brought attention to the growing seismic challenges associated with these structures. Although the prevalent use of friction pendulum bearings for seismic isolation in China has proven effective in mitigating the seismic response of bridges, it falls short of meeting the safety standards required for high-speed trains. To address the limitations of existing isolation systems, this study employs a combined approach of numerical simulation and experimental research, leading to the invention of performance-controllable isolation bearing and multi-directional energy dissipation dampers. Mechanical models for both components were introduced, and design methods for their key parameters were established based on multi-level seismic defense requirements. By integrating these advancements, a novel cooperative seismic isolation system for high-speed railway bridges was created. Under the influence of moderate earthquakes, the system relies on the shear key to meet the stiffness requirements for normal service. During large earthquakes, the shear key is sheared off, and the damper provides momentary stiffness to control track deformation, enabling the safe stopping of trains. This combination forms a seismic isolation system during large earthquakes, ensuring the safety of railway bridges. The numerical analysis of a high-speed railway bridge employing a cooperative seismic isolation system demonstrates substantial mitigation in the response of both the pier bottom and pier top. This aligns with seismic requirements for the bridge structure. Additionally, the reduction in train track deformation meets safety standards, confirming the seismic performance of bridges and ensuring the reliability of train operations.

Shaking table test of a dry-connection fully precast frame structure system

In view of the construction difficulties and ecological environment sensitivity of building construction in extremely cold and high seismic intensity areas, a new type of dry-connection fully precast frame structure system was proposed. The connections of the structure are easy to assemble, which can greatly improve the construction efficiency and provide convenience for the upgrading and replacement of components during service. In order to provide essential insights into the seismic performance of the dry-connection precast structure, a three-story precast frame structure specimen with a scale ratio of 1/2 was designed, constructed, and tested on a shaking table subjected to a series of ground motions with increasing seismic intensities. The connections of the specimen structure include beam-column joint, beam-floor joint and column-foundation joint, precast components were processed in the factory and assembled in the laboratory. The vibration characteristics, damage development, acceleration response and displacement response of the structure were investigated. The experimental results illustrated the excellent seismic performance of the structure with sufficient strength and relatively confined damage. The gradually decreasing frequency and increasing damping ratio were attributed to the slippage and plastic deformation of the connectors and the cracking of beam concrete. And the maximum story drift under rare earthquake of intensity 8 was within the design limit, indicated that the precast frame structure could achieve the performance target of no collapse under severe earthquakes. The data of this test provided support for further study on the design methods and numerical modeling of dry-connection fully precast frame structure systems.

A numerical investigation of the behavior of a tunnel with adaptive anti-dislocation measures subjected to the action of fault dislocation

In the context of long-distance cross-basin water transfer projects, the water conveyance tunnel serves as a pivotal component in mitigating regional disparities between economic development and water resources allocation. However, in high seismic-intensity areas of southwest China, geological complexities and densely distributed active faults present formidable challenges. Consequently, the construction of water conveyance tunnels necessitates traversing one or more active fault zones. This study examines the impact of an adaptive tunnel structure in the presence of fault dislocation, focusing on the Xianglushan Tunnel, a constituent of the Central Yunnan Water Diversion Project. Taking the Longpan-Qiaohou Fault F10-1 as a case study, we assess the influence of active faults on the anti-dislocation adaptive structure of the Xianglushan Tunnel, considering factors such as displacement, relative deformation, maximum principal stresses, and longitudinal equivalent internal force in critical tunnel sections. Numerical calculations validate the efficacy of this adaptive structure in reducing induced internal forces and deformations of the tunnel lining. The results show that, under the influence of strike-slip dominated fault movement, one side of the tunnel exhibits tensile stress, with a magnitude of approximately 5 MPa. The maximum normal and tangential deformation of the hinge joint is concentrated in the central section of the fault zone. The incorporation of an articulated adaptive design significantly enhances the stress state of lining under dislocation condition. These research results directly inform the engineering design and construction of water conveyance tunnels traversing active fault regions, providing valuable guidance for related tunnel construction endeavors.

Equipment response spectra for wind turbines considering the baseline control system

As more and more wind turbines are installed in areas with high seismic intensity, various published works have studied the seismic performance of wind turbines. However, these studies usually focus on the wind turbine, and less attention is paid to the electrical equipment mounted on the wind turbine. Electrical equipment is a non-structural component on wind turbine, which is prone to failure and damage, resulting in the loss of function of the wind turbine. Therefore, it is necessary to study the seismic performance of the electrical equipment installed on the wind turbine. This study focuses on evaluating and quantifying the dependence of equipment spectrum accelerations on the location of the electrical equipment in the structure, the damping ratio of the equipment, and the baseline control system. The baseline control system is used to control the output power by adjusting the rotor speed and the blade pitch angle, which affects the equipment spectrum of the wind turbines. There is a stronger relationship between the equipment response spectrum and the peak floor acceleration. Therefore, the equipment spectral amplification function is calculated as the ratio of the equipment spectral acceleration to the peak floor acceleration for different height. The equipment spectra amplification function is proposed and validated to estimate peak acceleration demands on the design of electrical equipment placed on wind turbines. The results indicate that current seismic code provisions will not always provide an adequate characterization of equipment accelerations. And the effect of wind turbine baseline control and equipment damping is more pronounced in the range of the structural tuning period than in the non-tuning range.

Shaking table tests on seismic behaviors of a single-layer spherical lattice shell with shape memory alloy-controlled friction pendulum bearings

An innovative seismic isolation device incorporating a friction pendulum bearing (FPB) and vertically aligned shape memory alloy (SMA) strands is proposed for the seismic control of spherical lattice shells located in strong-earthquake regions. To validate the effectiveness of the proposed SMA-FPBs experimentally, a 1/10-scale single-layer spherical lattice shell test structure and a set of isolators were designed and fabricated. A shaking table was used to apply various three-dimensional seismic excitations to test structures equipped with and without different isolation bearings (SMA-FPBs or bare FPBs). Significant seismic behavior enhancements were observed when such isolation systems were used. However, bare FPBs cannot accommodate excessive displacements induced by high seismic intensities owing to their lack of adaptive control. In contrast, SMA-FPBs exhibited satisfactory control performance in terms of the peak and residual bearing displacements under fortification and rare seismic actions, and the adaptive properties of the SMA-FPBs protected the isolators from disassembly owing to excessive sliding displacements under extremely rare earthquakes, even though their re-centering abilities decreased slightly because of the failure of several SMA wires. Finally, the larger number of SMA wires in an SMA-FPB enhanced its restraining capacity against peak bearing displacement rather than improving the seismic responses of structural nodes and members.

Fracture Mechanism of Dangling Concrete Pavement Slab in High Seismic Intensity Areas Along River

Fracture Mechanism of Dangling Concrete Pavement Slab in High Seismic Intensity Areas Along River

Deep Learning-Based Microseismic Detection and Location Reveal the Seismic Characteristics and Causes in the Xiluodu Reservoir, China

ABSTRACT The Xiluodu reservoir, as the third reservoir developed in the lower Jinsha River, is the fourth largest reservoir in the world in terms of power generation. It is located in an area of historically high seismic intensity. A large amount of seismic activity has occurred in the reservoir area because the reservoir was impounded in 2013, but the mechanism of seismogenesis is still not clear. In this study, we collected continuous seismic records from July 2020 to October 2022 in the Xiluodu reservoir area, built a high-precision microseismic catalog for this region based on a deep learning seismic detection and location workflow called LOC-FLOW, and eventually obtained high-precision locations of 4924 earthquakes (five times more than the routine catalog). We sketched the main seismogenic structures based on the spatial and temporal distribution of the earthquakes in the catalog. According to the relationship between periodic variation of water level and seismic activity, seismicity in the reservoir area is active at the stage when the water level is filling to the highest point and starts to draw down. Especially, the sudden change in the rate of water level variation can easily trigger seismic activity. Combined with the spatiotemporal distribution of seismicity in each region and the previous results of numerical simulation, we concluded that the seismic activity in the reservoir head area and around the Manao fault is likely induced by the increase of normal stress and pore pressure diffusion caused by reservoir impoundment, whereas the ML 4.6 earthquake that occurred at the intersection of the Lianfeng fault and the Zhongcun fault was likely tectonic activity occurring on a concealed fault.

Time-frequency characteristics investigation and numerical reconstruction of seismic-induced track irregularity for high-speed railway bridge

In recent years, the construction of high-speed railway has gradually extended to area with high seismic intensity. Seismic-induced track irregularity in high-speed railways is essential for evaluating high-speed railway safety upon earthquakes. Signals of seismic-induced track irregularity typically exhibit non-stationary characteristics, but research on the time–frequency characteristics of seismic-induced track irregularity on high-speed railways is currently limited. To ensure that high-speed train can continue to transport medical supplies and disaster rescuers after the earthquake, this study uses the simply supported beam bridge of the CRTS II ballastless track high-speed railway as the research object. It builds a sample database of post-earthquake residual track geometric irregularity based on the earthquake's randomness. In addition, this research investigates the effectiveness of different signal analysis methods, such as the Short time Fourier transform and wavelet transform, in reconstructing track geometric irregularity. A method of constructing the representative sample of seismic-induced track irregularity based on confidence level is proposed. The results indicated that: (1) Seismic-induced track irregularity in high-speed railway bridges is dominated by alignment irregularity; (2) The amplitude of the time–frequency spectrum for seismic-induced track irregularity in high-speed railway bridges decreases from low to high frequencies, and does not contain a significant high-frequency component; (3) Compared to Short time Fourier transform, wavelet transform is more effective in reconstructing post-earthquake track geometric irregularity; (4) Seismic-induced track geometric irregularity based on the wavelet transform can be a valuable indicator for evaluating the performance of a high-speed train on a bridge after an earthquake.

The formation mechanism of dynamic water and mud inrush geohazard triggered by deep-buried tunnel crossing active fault: Insights from the geomechanical model test

Water and mud inrush geohazard is one of the most important geohazards for underground engineering. Understanding the formation mechanism of water and mud inrush is critical for directing the prevention and control of this geohazard. As a result, a large number of methods have provided insight into this topic, such as the geomechanical model test. However, this geohazard triggered by deep-buried tunnel crossing active fault has not yet been explored. Thus, this study develops a geomechanical model test system to simulate the dynamic water and mud inrush caused by Kangding No.2 tunnel crossing Yunongxi active fault. The results imply that seismic loading can result in fluctuating changes in seepage pressure and stress in the tunnel rock mass. Increasing seismic intensity broadens the fluctuation range, together with a dramatic rise in peak seepage pressure. The coupled effect of earthquake loading and high seepage pressure makes the water-resisting rock mass extremely vulnerable to fracturing, increasing the probability of water and mud inrush. High seismic intensity leads to rock fracture propagation, ulteriorly giving rise to stress releasing, eventually provoking the fracturing of rock mass. Precursor of water and mud inrush can be observed before the geohazard occurs, reflected by the gradual rise of seepage pressure and intermittent fluctuation of stress. Following the increasing earthquake intensity, peak acceleration occurs in a random position of water-resisting rock mass, but mostly appears at the tunnel contour of surrounding rock. The free face of the tunnel exerts an amplifying effect on seismic acceleration. Seismicity affects the formation of water and mud inrush from active fault, which ulteriorly determines the minimum safety thickness of water-resisting rock mass. Monitoring the seepage pressure and stress in water-resisting rock mass is effective for the early warning of inrush hazard.

Kinematic deformation and intensity assessment of the 2021 Maduo MS7.4 earthquake in Qinghai revealed by high-frequency GNSS

Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue, disaster assessment, and future seismic risk research. The advancement of GNSS observation and data processing makes it play an important role in this field, especially the high-frequency GNSS. We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the MS7.4 Maduo earthquake epicenter. The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained. The results show that: 1) Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter. Coseismic response deformation on the east and west sides shows bilateral asymmetry, which markedly differs from the symmetry presented by surface rupture. 2) The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area, although the former is generally slightly smaller than the latter. 3) There may exist obstacles on the eastern side of the seismogenic fault. The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault (KPJF) and Maqin-Maqu segment, resulting in higher seismic risk in the future.

Dynamic Responses of Concrete-Face Rockfill Dam to Different Site Conditions under Near-Fault Earthquake Excitation

The western region of China is rich in hydropower resources and characterized by unique geological conditions. For the construction or planned construction of high dams in this region, different types of cover layers are formed due to special geological structures, most of which are located in high seismic intensity zones. This study focuses on four different site conditions: hard ground, medium–hard ground, medium–soft ground, and weak ground. By simulating the dynamic response of concrete-face rockfill dams under near-fault earthquake excitation, the vertical settlement of the dam and the attenuation of seismic motion under different site conditions are analyzed. The research findings reveal a consistent trend where the vertical settlement of the dams progressively escalates with increasing dam height across all four site conditions. This settlement phenomenon is especially pronounced in weak ground conditions, posing a potential risk of failure. Furthermore, when subjected to near-fault pulse-type earthquake motions, the existence of weak soil layers significantly dampens the seismic forces experienced by the dam. This finding suggests that the weaker the geological conditions of the site, the more pronounced the attenuation effect of the seismic motion. Additionally, the overburden layers have a noticeable amplification effect on near-fault pulse-type earthquake motion. However, this amplification effect is not significant in weak ground, possibly due to the presence of weak soil layers restricting the propagation and amplification of seismic motion. In conclusion, these research findings have practical significance for the dynamic response of high dam construction in different site conditions in the western region of China. They provide a scientific basis for the design and construction of high dams and serve as a reference for the implementation of seismic mitigation measures and earthquake disaster prevention in engineering projects.