岩土工程学报2023，Vol.45Issue(z2)：48-54,7.DOI:10.11779/CJGE2023S20014
坝基深厚覆盖层原状砂土动力特性
Dynamic properties of undisturbed sand in deep overburden of a dam foundation
摘要
Abstract
The ultra-deep overburden foundation is a great challenge for the construction of water conservancy and hydropower projects.The dynamic mechanical properties of overburden soil are the basis for discriminating liquefaction of foundation soil and analyzing dam stability.The sand layer in the ultra-deep overburden foundation of a proposed large-scale earth rock dam project is taken as the research object.A series of undrained cyclic triaxial tests are conducted on the undisturbed soil samples(directly extracted from an ultra-deep in-situ test well)and remolded soil samples under high confining pressure conditions.The laboratory results demonstrate that the dynamic strength of the undisturbed sand is higher than that of the remolded sand,and the difference between them gradually decreases with the increase of the confining pressure.The evolution laws of pore pressure and axial strain of the undisturbed and remolded soil samples are similar.The consolidation stress ratio has obvious influences on both the dynamic strength index and the failure mode of the soil samples.With the increase of the consolidation stress ratio,the dynamic strength increases,and the failure mode of the soil samples gradually changes from liquefaction failure to plastic strain accumulation one.关键词
坝基深厚覆盖层/原状砂土/不排水动三轴试验/动强度/高围压/动力特性Key words
deep riverbed overburden/undisturbed sand/dynamic unconsolidated undrained triaxial test/dynamic strength/high confining pressure/dynamic property分类
建筑与水利引用本文复制引用
禹艳阳,彭文明,李建,罗启迅,马付龙,陈聪,刘恩龙..坝基深厚覆盖层原状砂土动力特性[J].岩土工程学报,2023,45(z2):48-54,7.基金项目
国家自然科学基金项目(12372376) （12372376）
