The control of earthquake sequences on hillslope stability
The control of earthquake sequences on hillslope stability
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DOI：
10.1002/2016gl071879
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发表时间：
2017-01
影响因子：
5.2
通讯作者：
M. Brain;N. Rosser;N. Tunstall
中科院分区：
文献类型：
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作者：
M. Brain;N. Rosser;N. Tunstall
地震在山区引发山体滑坡。最近的研究表明，在大地震期间和之后，山坡的稳定性受到先前地震活动的遗留效应的影响。然而，延性山坡材料的抗剪强度和应变响应对不同特征的地震地面震动序列的约束很差，这限制了我们充分解释地震引发的滑坡性质的能力。我们使用岩土工程实验室测试来模拟山坡的地震载荷，并评估不同的地面震动序列在地震主震之前、期间和之后如何影响山坡的稳定性。主震前的地震事件不会导致高滑坡应变积累，但会增加体密度和颗粒间摩擦。这加强了山坡，在随后的地震活动中减少了滑坡位移。由此可见，由于地震的震级、频率和顺序的不同，不同构造环境下的景观可能对单次地震表现出不同的短期和长期反应。
Earthquakes trigger landslides in mountainous regions. Recent research suggests that the stability of hillslopes during and after a large earthquake is influenced by legacy effects of previous seismic activity. However, the shear strength and strain response of ductile hillslope materials to sequences of earthquake ground shaking of varying character is poorly constrained, inhibiting our ability to fully explain the nature of earthquake‐triggered landslides. We used geotechnical laboratory testing to simulate earthquake loading of hillslopes and to assess how different sequences of ground shaking influence hillslope stability prior to, during, and following an earthquake mainshock. Ground‐shaking events prior to a mainshock that do not result in high landslide strain accumulation can increase bulk density and interparticle friction. This strengthens a hillslope, reducing landslide displacement during subsequent seismicity. By implication, landscapes in different tectonic settings will likely demonstrate different short‐ and long‐term responses to single earthquakes due to differences in the magnitude, frequency, and sequencing of earthquakes.