考虑温度效应下海砂动力特性试验研究  

Experimental study on dynamic characteristics of sea sand considering temperature effect

作　　者：王家全[1,2] 和玉 林志南 唐毅 Wang Jiaquan;He Yu;Lin Zhinan;Tang Yi(Guangxi University Key Laboratory of Disaster Prevention and Mitigation and Prestress Technology,Guangxi University of Science and Technology,Liuzhou 545006,China;Geotechnical Disaster and Ecological Management Engineering Research Center of Guangxi Zhuang Autonomous Region,Liuzhou 545006,China)

机构地区：[1]广西科技大学广西高校防灾减灾与预应力技术重点实验室,广西柳州545006 [2]广西壮族自治区岩土灾变与生态治理工程研究中心,广西柳州545006

出　　处：《土木工程学报》2025年第2期118-128,共11页China Civil Engineering Journal

基　　金：国家自然科学基金(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(桂教人才[2020]6号);广西科技大学研究生教育创新计划(GKYC202328)。

摘　　要：针对温度对海砂动力特性的影响研究不足,在现有的GDS动三轴试验系统中增添JULABO温度模块,开展考虑温度效应的固结不排水动三轴试验,探究了温度和动应力幅值对广西北部湾海砂累积塑性应变、动弹性模量及动孔压的影响规律。研究表明:北部湾海砂的累积塑性应变曲线整体呈现破坏型发展趋势,升温引起北部湾海砂的应变累积速率加快,在动应力幅值较大时,升温引起北部湾海砂的累积塑性应变明显增加,在循环加载后期发生液化;在升温条件下,温度对北部湾海砂孔压发展有显著影响,海砂在高温环境下表现出较强的循环活动性,且液化程度加重;北部湾海砂在循环加载过程中出现刚度软化现象,温度升高可以降低北部湾海砂的初始动弹性模量;幂函数能较好地描述北部湾海砂动弹性模量Ed与轴向累积应变ε_(d)的关系,在此基础上建立了不同温度下动弹性模量与动应变的预测模型,该模型能够较好预测北部湾海砂在不同温度下的动弹性模量。研究成果为考虑温度效应下海砂作为填料的工程提供了理论指导。In view of the lack of research on the influence of temperature on the dynamic characteristics of sea sand,the temperature module JULABO was added to the existing dynamic triaxial test system of GDS,and the consolidated-undrained dynamic triaxial test considering temperature effect was carried out to explore the influence laws of temperature and dynamic stress amplitude on the cumulative plastic strain,dynamic elastic modulus and dynamic pore pressure of sea sand in the Beibu Gulf.The results show that the cumulative plastic strain curve of the sand in the Beibu Gulf presents an overall destructive trend.The strain accumulation rate of the sand in the Beibu Gulf is accelerated by rising temperature.When the dynamic stress amplitude is large,the cumulative plastic strain of the sand in the Beibu Gulf is markedly increased by rising temperature,and liquefaction occurs in the late stage of cyclic loading.Under the condition of rising temperature,the temperature has a significant effect on the pore pressure development of the sea sand in the Beibu Gulf,and the sea sand presents strong cyclic activity and the liquefaction degree is increased under the high temperature environment.Stiffness softening occurs in the process of cyclic loading,and the initial dynamic elastic modulus of the sea sand can be reduced with the rise of temperature.The relationship between the dynamic elastic modulus E_d and the axial cumulative strainε_(d)of the Beibu Gulf sea sand can be well described by the power function.On this basis,a prediction model of the dynamic elastic modulus and dynamic strain at different temperatures is established,which can better predict the dynamic elastic modulus of the Beibu Gulf sea sand at different temperatures.The research results provide theoretical guidance for the project with sea sand used as fill material considering the temperature effect.

关 键 词：北部湾海砂 温度效应 动弹性模量 孔压模型 温控三轴仪 

分 类 号：TU411[建筑科学—岩土工程]