Mechanical properties of sandstones after high temperature under dynamic loading
YIN Tu-bing1, 2, LI Xi-bing1, 2, WANG Bin1, 2, YIN Zhi-qiang1, 2, JIN Jie-fang1, 2
1. School of Resources and Safety Engineering, Central South University, Changsha 410083, China; 2. Hunan Key Laboratory of Resources Exploitation and Hazard Control for Deep Metal Mines, Changsha 410083, China;
Abstract：The mechanical properties of sandstone specimens such as density, longitudinal wave velocity, peak dynamic strength are studied under dynamic compression loading after being heated at different temperatures (25℃～800℃). Dynamic fragmentation characteristics of sandstone specimens are analyzed from different aspects of failure mode, fragment distribution and high-speed photography. The testing device of SHPB is adopted to conduct the dynamic experiments of rock specimens experiencing high temperatures. Though the experimental results are discrete, the general law is obvious. The results show that, with the increasing temperature, the specimen density, the longitudinal wave velocity and the peak strength all gradually decrease, and the decreased magnitude of the longitudinal wave velocity increases when the temperature is over 200℃. And the temperature changes from 400℃ to 600℃，the peak strength of rock has less decreased magnitude, and decreases sharply when the temperature is over 800℃. The dynamic failure characteristics of sandstone are mainly tensile failure after high temperature, with the increasing temperature, when rock fragmentation degrees increase, rock blocks become smaller. Through high-speed photography, dynamic failure process of rock is expressed. It is obtained that radial cracks are distributed around the specimens along the loading direction, the failure mode of rock is not representative at the initial loading, but the final failure mode of rock is obtained through the stress wave multiple reflection.
尹土兵，李夕兵，王 斌，殷志强，金解放. 高温后砂岩动态压缩条件下力学特性研究[J]. 岩土工程学报, 2011, 33(5): 777-.
YIN Tu-bing, LI Xi-bing, WANG Bin, YIN Zhi-qiang, JIN Jie-fang. Mechanical properties of sandstones after high temperature under dynamic loading. Chinese J. Geot. Eng., 2011, 33(5): 777-.
