基于边界效应模型对高温后花岗岩断裂破坏预测  

Prediction of Fracture Failure of Post-High-Temperature Granite Based on Boundary Effect Model

作　　者：林建伟 高经武[1] 武晋文 吕琪 王学怀 LIN Jianwei;GAO Jingwu;WU Jinwen;LYU Qi;Wang Xuehuai(Science College,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学理学院,太原030051

出　　处：《重庆理工大学学报（自然科学）》2020年第5期99-106,156,共9页Journal of Chongqing University of Technology：Natural Science

基　　金：国家自然科学基金青年基金资助项目(51504220)。

摘　　要：为分析高温后岩石断裂破坏特性并预测其断裂破坏,采用考虑岩石颗粒尺寸边界效应模型对不同温度(25~900℃)作用后鲁灰花岗岩断裂破坏进行研究。研究结果表明:常温下鲁灰花岗岩边界效应模型离散系数β取2.0左右,可通过已知抗拉强度和一种尺寸下的三点弯试验数据的方法得到高温作用后鲁灰花岗岩的边界效应曲线,与其他三种岩石进行对比并验证了方法的正确性;分析不同温度对考虑岩石颗粒尺寸边界效应模型的影响,提出在模型中增加温度系数αT,得到不同温度下鲁灰花岗岩αT的变化;根据确定的参数建立不同温度作用后鲁灰花岗岩断裂破坏全曲线,对其断裂破坏进行预测。In order to analyze the fracture characteristics of rocks after high temperature and predict its fracture failure,the fracture damages of Lu gray granite after different temperatures( 25 ~ 900 ℃)were studied by considering the boundary model of rock particle size. The results show that the model dispersion coefficient β of Lu gray granite is about 2. 0 at room temperature. The boundary effect curve of the Lu gray granite can be obtained by the method of known tensile strength with three-point bending test data under one size. The correctness of this method is tested by comparing with the other three rocks ’ test results. The influence of different temperatures on the boundary effect model considering rock particle size is analyzed. It is proposed to increase the temperature coefficient α_T in the model to obtain the changes of the ash granite α_T at different temperatures. According to the determined parameters,the complete fracture and failure curves of Lu gray granite at different temperatures are established,and the fracture failure is predicted.

关 键 词：高温岩石 边界效应 岩石颗粒尺寸 断裂韧度 抗拉强度 

分 类 号：TU45[建筑科学—岩土工程]