摘要
为揭示不同排水条件、细粒含量下饱和砾砂动力特性的发展规律,通过室内动三轴试验对其动力特性进行相关测试,探究了排水条件、细粒含量以及动应力幅值对饱和砾砂轴向累积应变、回弹模量、体积应变及动孔压的影响。结果表明:三级循环荷载下不同排水条件试样轴向累积应变随细粒含量的增加不断增大,其骨干曲线符合Hardin-Drnevich双曲线模型。排水条件下轴向累积应变均大于不排水条件。高细粒含量及排水条件下试样的回弹模量较小,不排水条件下振次N=9000时细粒含量F_(c)=15%的回弹模量相比于F_(c)=0%减小了20.284%。各试验工况下试样体积变形整体以体缩为主,动孔压随振次的发展曲线可分为峰值型、增长型、衰减型及平稳型4种发展模式。
In order to reveal the development rule of dynamic characteristics of saturated gravel sand under different drainage conditions and fines content,the dynamic characteristics of saturated gravel sand were tested by indoor dynamic triaxial test,and the effects of drainage conditions,fines content and dynamic stress amplitude on the axial cumulative strain,elastic modulus,volumetric strain and dynamic pore pressure of saturated gravel sand were investigated.The results show that under three-level cyclic loading,the axial cumulative strain of the specimens under different drainage conditions increases continuously with the increase of fines content,and the backbone curve conforms to the Hardin-Drnevich hyperbolic model.The axial cumulative strain under the drainage conditions are all larger than those under the undrained condition.Samples with high fines content and drainage have lower modulus of resilience.Under undrained conditions,the elastic modulus of fines content F_(c)=15%decreased by 20.284%compared with F_(c)=0%when vibration times N=9000.Under each test condition,the volume deformation of the sample is dominated by volume shrinkage.The development curve of dynamic pore pressure with vibration order can be divided into four development modes that are peak type,growth type,decay type and stable type.
作者
王家全
王晴
祝梦柯
畅振超
WANG Jiaquan;WANG Qing;ZHU Mengke;CHANG Zhenchao(College of Civil and Architectural Engineering,Guangxi University of Science and Technology,Liuzhou 545006,China;Guangxi Zhuang Autonomous Region Engineering Research Center of Geotechnical Disaster and Ecological Control,Liuzhou 545006,China;Guangxi Beitou Transportation Maintenance Technology Group Co.,Ltd.,Nanning 530029,China;Guangxi University Key Laboratory of Disaster Prevention and Mitigation and Prestress Technology,Liuzhou 545006,China)
出处
《自然灾害学报》
CSCD
北大核心
2023年第4期239-248,共10页
Journal of Natural Disasters
基金
国家自然科学基金项目(41962017)
广西自然科学基金重点项目(2022GXNSFDA035081)
广西高等学校高水平创新团队及卓越学者计划项目(桂教人才〔2020〕6号)
国家级(广西)大学生创新创业训练计划资助项目(202010594035)。
关键词
砾砂
排水条件
细粒含量
动力特性
三级加载
gravel
drainage conditions
fines content
dynamic characteristics
three-level loading
