摘要
为研究增湿、加压及振动荷载耦合作用下黄土的变形特性,在初始含水量为5%、10%、15%、20%以及固结压力为50、100、150、200kPa和动剪应变幅为0.15%、0.5%、1.0%、2.2%、3.3%、4.5%条件下对原状Q_(3)黄土开展了动单剪试验。试验结果显示,震陷变形及其单周次增幅均随剪应变增大而增大;在低含水量条件下,随固结压力增大,震陷变形增幅明显;高含水量条件下,压—震作用则对震陷变形显示不同的影响规律;低固结压力条件下,随含水量增加,震陷变形增幅明显;而高固结压力条件下,湿—震作用也对震陷变形呈现不同的影响规律。由此认为,剪应变幅、固结压力和含水量对黄土震陷的影响作用明显,任一影响因素的增大都使得震陷变形变大。固结压力和含水量对震陷变形的影响需考虑两者之间的耦合作用,当任一变量增加至某一临界值时,另一变量产生的影响作用将变得相对较弱。
To study the deformation characteristics of loess under the moisture-pressure-vibration coupling,dynamic simple shear tests were conducted on undisturbed Q_(3)loess under initial water contents of 5%,10%,15%,and 20%,consolidation pressures of 50,100,150,and 200 kPa,and dynamic shear strain amplitudes of 0.15%,0.5%,1.0%,2.2%,3.3%,and 4.5%.The test results show that both the seismic subsidence and its single-cycle increment increase with the shear strain.Under low water content conditions,the seismic subsidence deformation increases significantly as consolidation pressure increases.Under high water content conditions,the compression-vibration effect shows different patterns of influence on seismic subsidence deformation.Under low consolidation pressure conditions,seismic subsidence deformatopn increases significantly with the increase of water content,while under high consolidation pressure conditions,the moisture-vibration effect also shows different patterns of influence on seismic subsidence deformation.It is concluded that shear strain amplitude,consolidation pressure,and water content have obvious effects on the seismic subsidence of loess,with the increase of any influencing factor leading to larger seismic subsidence.The influence of consolidation pressure and water content on seismic subsidence deformation needs to consider the coupling effect between them.When either variable reaches a critical value,the influence of the other variable will become relatively weak.
作者
王强
邵生俊
张喆
邓国华
WANG Qiang;SHAO Shengjun;ZHANG Zhe;DENG Guohua(Xianyang Engineering Technology Research Center for Loess Mechanics and Disaster Prevention,Shaanxi Polytechnic University,Xianyang 712000,China;Shaanxi Key Laboratory of Yellow Soil Mechanics and Engineering,Xi’an University of Technology,Xi’an 710048,China;Xi’an Loess Underground Engineering Technology Consulting Co.,Ltd.,Xi’an 710054,China)
出处
《华南地震》
2025年第2期137-145,共9页
South China Journal of Seismology
基金
国家自然科学基金项目(52178355)
博士基金(BSJ2021-08)联合资助。
关键词
原状黄土
黄土震陷
动单剪试验
耦合作用
Undisturbed loess
Loess seismic subsidence
Dynamic simple shear test
Coupling effect
