摘要
采用改进后具有主动围压加载装置的100mm分离式Hopkinson压杆(SHPB)试验装置,研究了斜长角闪岩在不同围压等级(0MPa～6MPa)和不同应变率(50s 1～170s 1)下的冲击压缩力学性能。试验结果表明:在相同围压下,斜长角闪岩的动态抗压强度随应变率的增加而近似线性增加,动态增长因子与应变率的对数呈近似线性关系,体现了显著的应变率相关性;在同等级应变率范围内,随着围压的增加,岩石的增强效果逐渐增强,显现出较强的围压效应。采用组合建模的方法,将统计损伤模型和粘弹性模型相结合,建立了基于Weibull分布的动态损伤本构模型。验证发现,修正后的模型曲线和试验曲线吻合较好,表明所构建本构模型是合理的,可为进一步研究和工程应用提供一定的参考。
In order to test the impact mechanical properties of rock, the amphibolites are subjected to impact loads with different confining pressures （0MPa-6MPa） and strain rates （50s-1-170s-1） by using the improved SHPB of 100mm diameter. The SHPB has confining pressure device. Experimental results show that under the same confining pressure, the dynamic compressive strength of amphibolites are strain-rate dependent, and the strain-rate effect can be expressed by linear approximations, so the relationship between the dynamic increase factor and the logarithm of strain-rate is approximately linear. The strengthening effect gets more prominent with the increase of conf＇ming pressure at the same range of strain rates. The damage constitutive model of rock under dynamical load based on weibuU distribution is established through combining statistic damage model and visco-elastic model. It is found that the theoretical curves and experimental curves are in good agreement, indicating the constitutive model is reliable. It can offer reference for further research on rock mechanical properties and engineering application in underground engineering.
出处
《工程力学》
EI
CSCD
北大核心
2012年第1期55-63,共9页
Engineering Mechanics
基金
国家自然科学基金项目(51078350)
陕西省自然科学基金项目(SJ08E210)
