人工模拟节理峰值剪胀模型及峰值抗剪强度分析  

ANALYSIS OF PEAK DILATION STRENGTH AND MODEL OF PEAK DILATION ANGLE FOR ARTIFICIAL JOINT

作　　者：唐志成[1,2] 夏才初[1,2] 宋英龙[1,2] 付朋方[2] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092

出　　处：《岩石力学与工程学报》2012年第A01期3038-3044,共7页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(40972178)

摘　　要：在5级法向应力作用下对具有相同形貌的人工模拟材料偶合节理进行直剪试验,探讨剪胀角、峰值剪切强度与法向应力、节理表面形貌的关系。采用常用的Barton剪胀模型、Schneider剪胀模型、Jing剪胀模型分析直剪试验实测的峰值剪胀角,结果表明模型计算值与试验实测值存在一定的偏差:Schneider剪胀模型与Jing剪胀模型在低法向应力下预测值过小、在高法向应力下预测值偏大,Barton剪胀模型与试验值相差较远。分析剪胀角存在的边界条件,以t n(/)为参量提出双曲线形式的峰值剪胀模型,进而提出新的峰值强度公式。将新的峰值强度公式,上述3种剪胀模型对应的强度公式及GG强度公式所得的峰值强度与试验数据进行对比分析,结果表明新强度公式预测值更接近试验值。Several shear tests have been conducted on different artificial joint samples at 5-level normal stress to study the relationships between peak shear dilation angle, peak shear strength and normal stress, joint roughness. These samples have the same morphology. The experimental results are analyzed by commonly used dilation models, which are Barton peak dilation model, Schneider peak dilation model and Jing peak dilation model. The analysis results show that there are some difference between the observed value and predicted value by these models. Usually, the predicted value under low normal stress for Schneider model and Jing model is too small, but that under high normal stress is too large. The results also show that there is a large difference between observed value and results calculated by Barton dilation model. After analyzing the boundary condition of existence of shear dilation angle, a new hyperbolic peak dilation model is put forward, using（o-,/~） as model parameter. A new peak shear strength criterion is proposed based on this new peak dilation model. The experimental data are compared with peak strengths calculated by this new peak shear strength criterion, the above three strength criteria and GG strength criterion. There is a good agreement between new strength criterion and observed data.

关 键 词：岩石力学 节理 峰值剪胀角 峰值强度 

分 类 号：TU45[建筑科学—岩土工程]