Mag Intro

Mag Intro Mag Intro

Quick Entry

  • Author Login Author Login
  • Reviewer Login Reviewer Login
  • Editor-in-chief Editor-in-chief
  • Editor Login Editor Login
  • Editor's Recommendation
更多

Editor's Recommendation

更多

Nonlinear Site Effects in Deep Soft Deposits: A Century of Observations, Insights, and Future Challenges

Local site conditions, particularly those involving thick sedimentary layers that are susceptible to the amplification effects, can significantly modify seismic ground motions, often exacerbating structural damage and posing catastrophic risks to major cities. To advance risk assessment and mitigation for future mega-earthquakes, this paper presents a systematic and critical review of the global observations and insights from the past century on nonlinear site effects in deep soft soil deposits. It focuses on the evolution, current state, and persistent challenges in site response analysis methodologies. First, drawing on macroseismic site effect phenomena and strong-motion records from regions such as the San Francisco Bay Area (1906 MW7.8 and 1989 MW6.9 earthquakes), the Mexico City Basin (1985 MW8.1 and 2017 MW7.1 earthquakes), the Weihe Basin (2008 Wenchuan MS8.0 earthquake), and the Tokyo Bay Area (e.g., 1923 MW7.9 and 2011 MW9.1 earthquakes), we reveal characteristic features of nonlinear site amplification in deep alluvial plains and sedimentary basins. These include pronounced amplification of long-period ground motions from far-field large earthquakes, prolongation of strong shaking, site-structure double resonance effect, and basin-edge effects, among others. Next, we outline the development of site response analysis methods and corresponding software, from one-dimensional frequency-domain equivalent linear analysis to time-domain nonlinear methods (total stress and effective stress approaches), and further to complex two- and three-dimensional nonlinear wave propagation simulations. The theoretical principles, validation against downhole array recordings, applicability, and limitations of these approaches are extensively discussed. Finally, considering potential extreme earthquake risks facing metropolitan regions in China's alluvial plains composed of deep soft soil deposits (e.g. the Haihe Plain and Yangtze River Delta), we identify three fundamental issues: (1) constitutive models capable of capturing the strong nonlinear behavior of very deep soft soil deposits; (2) the construction of regional-scale numerical models that reasonably represent not only the inherent spatial variability of extremely deep, complex deposits, but also the associated parameter uncertainties; and (3) the development of efficient yet high-precision 2D and 3D nonlinear wave simulation methods. Addressing these challenges is crucial for deepening the fundamental understanding of site effects and establishing a robust scientific basis for enhancing urban seismic resilience against future mega-earthquakes.

CHEN Guoxing, FANG Yi, WU Shuanglan, WU Qi, Charng Hsein JUANG

Nonlinear Site Effects in Deep Soft Deposits: A Century of Observations, Insights, and Future Challenges
  • Current Issue
  • Online First
  • Archive
更多
Volume 46 期 2，2026 2026年第46卷第2期

    CHEN Guoxing, FANG Yi, WU Shuanglan, WU Qi, Charng Hsein JUANG

    Vol. 46, Issue 2, Pages: 211-290(2026) DOI: 10.13409/j.cnki.jdpme20260117003
    摘要：Local site conditions, particularly those involving thick sedimentary layers that are susceptible to the amplification effects, can significantly modify seismic ground motions, often exacerbating structural damage and posing catastrophic risks to major cities. To advance risk assessment and mitigation for future mega-earthquakes, this paper presents a systematic and critical review of the global observations and insights from the past century on nonlinear site effects in deep soft soil deposits. It focuses on the evolution, current state, and persistent challenges in site response analysis methodologies. First, drawing on macroseismic site effect phenomena and strong-motion records from regions such as the San Francisco Bay Area (1906 MW7.8 and 1989 MW6.9 earthquakes), the Mexico City Basin (1985 MW8.1 and 2017 MW7.1 earthquakes), the Weihe Basin (2008 Wenchuan MS8.0 earthquake), and the Tokyo Bay Area (e.g., 1923 MW7.9 and 2011 MW9.1 earthquakes), we reveal characteristic features of nonlinear site amplification in deep alluvial plains and sedimentary basins. These include pronounced amplification of long-period ground motions from far-field large earthquakes, prolongation of strong shaking, site-structure double resonance effect, and basin-edge effects, among others. Next, we outline the development of site response analysis methods and corresponding software, from one-dimensional frequency-domain equivalent linear analysis to time-domain nonlinear methods (total stress and effective stress approaches), and further to complex two- and three-dimensional nonlinear wave propagation simulations. The theoretical principles, validation against downhole array recordings, applicability, and limitations of these approaches are extensively discussed. Finally, considering potential extreme earthquake risks facing metropolitan regions in China's alluvial plains composed of deep soft soil deposits (e.g. the Haihe Plain and Yangtze River Delta), we identify three fundamental issues: (1) constitutive models capable of capturing the strong nonlinear behavior of very deep soft soil deposits; (2) the construction of regional-scale numerical models that reasonably represent not only the inherent spatial variability of extremely deep, complex deposits, but also the associated parameter uncertainties; and (3) the development of efficient yet high-precision 2D and 3D nonlinear wave simulation methods. Addressing these challenges is crucial for deepening the fundamental understanding of site effects and establishing a robust scientific basis for enhancing urban seismic resilience against future mega-earthquakes.  
    关键词：Seismic site effects;Deep soft deposits;Basin effects;Long-period ground motion amplification;Soil nonlinearity;Strong motion records;Site response analysis techniques   
    91
    |
    50
    |
    0
    <HTML>
    <L-PDF><WORD><Meta-XML>
    <引用本文> <批量引用> 149586471 false
    更新时间：2026-04-15

    PAN Yi, LIU Fanglin, GUO Xin, CHEN Zifeng, LIN Xuchuan

    Vol. 46, Issue 2, Pages: 291-302(2026) DOI: 10.13409/j.cnki.jdpme.20250708003
    摘要：Falling debris from buildings along streets during strong earthquakes often affects the capacity of urban roads in disaster-affected areas to varying degrees. Taking Moxi Town in the mountainous area of western Sichuan Province as the study area, this study investigated the degradation of road capacity caused by the 2022 Luding Ms 6.8 earthquake and analyzed the influence mechanisms of falling debris on the post-earthquake transportation system. Based on seismic damage surveys and remote sensing imagery data, an elastoplastic time-history analysis model for building clusters and a multi-body dynamics collapse model were established to simulate the seismic damage of building clusters in Moxi Town during the Luding earthquake and to assess the spatial distribution of falling debris. On this basis, the effects of seismic intensity, building structural types, and other factors on the distribution of falling debris and road capacity in mountainous towns were analyzed. The results showed that the distribution range and morphology of falling debris obtained by the simulation method in this study were basically consistent with the results of actual seismic damage surveys. The spatial distribution of building falling debris was significantly affected by earthquake intensity, structure type, and topographic location. As earthquake intensity increased, the coverage of falling debris expanded, with a significant increase observed for brick masonry structures and structures without seismic fortification. The unique topographic characteristics of the Moxi terrace resulted in a larger distribution range of falling debris from buildings at the terrace edge than those in the central area of the terrace. Under the 9-degree fortification ground motion, the capacity of some road sections decreased by more than 50%. When the seismic action reached the 9-degree extremely rare earthquake level, the proportion of blocked road sections exceeded 70%, and the transportation system was close to paralysis. This study provides a reference for planning earthquake emergency rescue routes and post-earthquake traffic restoration in mountainous towns of southwestern China.  
    关键词：building collapse;road capacity;seismic damage survey;falling debris simulation;falling debris distribution   
    11
    |
    3
    |
    0
    <HTML>
    <L-PDF><WORD><Meta-XML>
    <引用本文> <批量引用> 154626031 false
    更新时间：2026-04-15

    ZHU Hongbing, HE Hao, DUAN Yixue, FU Zhenghao

    Vol. 46, Issue 2, Pages: 303-312(2026) DOI: 10.13409/j.cnki.jdpme.20240904003
    摘要：Full-lightweight ceramsite concrete has the advantage of causing only a small increase in structural self-weight when used to reinforce concrete components. The degradation behavior of the bond interface between it and existing concrete is crucial for evaluating the durability deterioration of reinforced components in the seawater environment. Lightweight aggregate concrete-ordinary concrete bond interface specimens with three types of interfacial agents (epoxy resin, cement paste, acrylic acid) and three roughness levels (1, 3, and 5 mm) were subjected to high-temperature accelerated erosion in artificial seawater solution for 0 to 150 days. Slant shear tests were then conducted on the eroded interface specimens to analyze the morphological changes of the specimens, shear failure modes, and the degradation patterns of bond strength. The results showed that during the erosion process in the seawater environment, the interfacial shear failure mode of the specimens gradually changed from mixed cohesive failure to bond failure with increasing erosion time. The interfacial bond strength first increased slowly and then decreased significantly with increasing erosion time. At 60 days of erosion, the epoxy resin interface with roughness of 3 mm had the highest slant shear strength of 19.95 MPa. The maximum reduction in slant shear strength of the concrete interface after 150 days of erosion was 23%. After 150 days of erosion in the seawater solution, the slant shear strength of the interface under the roughness levels of 1, 3, and 5 mm decreased by 22.65%, 21.75%, and 22.93%, respectively, compared with that before erosion. Appropriate interfacial roughening treatment can improve the corrosion resistance of the concrete interface. During the erosion process, under the same roughness level, the maximum slant shear strengths of the specimens using epoxy resin interfacial agents were greater than those using cement paste and acrylic acid. Regardless of the roughness level and interfacial agent used, the effect of the seawater environment on the interfacial slant shear strength was very significant (all F-values were greater than F0.025). The findings are significant for evaluating the degradation of interfacial durability performance of existing concrete structures reinforced with lightweight aggregate concrete in the seawater environment.  
    关键词：full-lightweight ceramsite concrete;ordinary concrete;interface bonding;shear strength;seawater environment   
    12
    |
    6
    |
    0
    <HTML>
    <L-PDF><WORD><Meta-XML>
    <引用本文> <批量引用> 154626353 false
    更新时间：2026-04-15

    GAO Luqiao, LI Guoqiang, ZHENG Xiuzhi, LIU Bing

    Vol. 46, Issue 2, Pages: 313-324(2026) DOI: 10.13409/j.cnki.jdpme.20240923003
    摘要：Steel-timber composite columns are a new type of prefabricated component that is green, low-carbon, and highly efficient in load-bearing. However, research on their fire resistance performance remains notably limited. Numerical analysis methods were employed to investigate the fire resistance performance of steel-timber composite columns. Firstly, a numerical analysis model for the fire resistance performance of steel-timber composite columns considering thermal coupling effects was established. The accuracy of the numerical model was then verified using fire test data. Subsequently, based on the validated numerical analysis model, the fire resistance performance of steel-timber composite columns was simulated. Their axial displacement, fire-induced failure mode, and fire resistance were revealed and compared with those of pure steel (timber) columns. Finally, parameter analysis was conducted to investigate the effects of timber density, moisture content, encasing timber thickness, and steel ratio on the fire resistance of steel-timber composite columns. The results indicated that for composite columns with low load ratios, axial deformation was dominated by thermal expansion, whereas for those with high load ratios, axial deformation was dominated by compressive deformation. There were mainly two failure modes of axially loaded steel-timber composite columns under fire conditions. Short columns with small slenderness ratios primarily underwent strength failure, while long and slender columns with large slenderness ratios both experienced overall buckling failure. The load ratio and slenderness ratio significantly influenced the fire resistance of steel-timber composite columns. Timber density, moisture content, encasing timber thickness, and steel ratio also had a significant impact on the fire resistance of steel-timber composite columns, but their influence trends differed between short and long columns. In addition, the fire resistance of steel-timber composite columns exceeded that of pure steel (timber) columns, and the smaller the load ratio, the greater the increase in the fire resistance of the steel-timber composite columns.  
    关键词：steel-timber composite column;fire resistance performance;numerical analysis;fire resistance;parameter analysis   
    15
    |
    2
    |
    0
    <HTML>
    <L-PDF><WORD><Meta-XML>
    <引用本文> <批量引用> 154626321 false
    更新时间：2026-04-15
查看更多

0