动荷载对干湿循环后饱水砂岩的力学性能研究试验  

Experimental Study on Mechanical Properties of Saturated Sandstone After Dry and Wet Cycling Under Dynamic Loading

作　　者：平琦[1] 孙栋 刘子训 PING Qi;SUN Dong;LIU Zixun(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan,Anhui 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《九江学院学报(自然科学版)》2025年第1期37-41,共5页Journal of Jiujiang University:Natural Science Edition

基　　金：国家自然科学基金资助项目(编号52074005,52074006);安徽省自然科学基金(编号1808085ME134)的研究成果之一。

摘　　要：由于降雨等原因引起地下水位升降,深部岩体经常处于干湿循环后饱水状态,岩石受动荷载作用的动态力学性质会发生改变,为研究干湿循环后不同加载速率对干湿循环后饱水砂岩动态压缩力学性能的影响,文章利用霍普金森压杆(SHPB)试验装置开展5种加载速率动态压缩试验。结果表明:干湿循环后饱水砂岩动应力-应变曲线先增后减,随加载速率增加,曲线整体向左上方移动;动应力、动应变、平均应变率均与加载速率呈二次函数正相关;破碎块度平均粒径与加载速率呈幂函数负相关性,加载速率增加,破碎程度加剧;随加载速率增加,砂岩内部应力集中明显,加速裂纹无序扩展,使砂岩动力学性能有一定程度提升。Due to fluctuations in groundwater levels from rainfall and other environmental factors,deep rock masses were often exposed to post-wetting and cyclic dry-wet conditions.Under these conditions,the dynamic mechanical properties of rock could change significantly under dynamic loads.This study examined the impact of varying loading rates on the dynamic compressive properties of water-saturated sandstone after dry-wet cycling.Using a Split Hopkinson Pressure Bar(SHPB)device,dynamic compression tests were conducted at five different loading rates.Results indicate that,after the dry-wet cycle,the dynamic stress-strain curve of water-saturated sandstone initially increased and then decreased,shifting upward and leftward as loading rates increase.Dynamic stress,dynamic strain,and average strain rate all exhibited a quadratic positive correlation with loading rate.Meanwhile,the average particle size of the fragmented sandstone mass showed a negative power-law correlation with loading rate.As loading rate increases,internal stress concentration within the sandstone intensifies,crack propagation accelerates,and the dynamic performance of the sandstone improved to some extent.

关 键 词：岩石动力学 饱水状态 干湿循环 冲击压缩 SHPB装置 

分 类 号：TU45[建筑科学—岩土工程]