动态巴西圆盘劈裂试验的极限分析解

通过极限分析上限定理对巴西圆盘动态劈裂试验的弹性解进行了优化,考虑高速冲击作用导致的岩石试件端部剪切裂纹对动态拉伸强度的影响,获得了计算动态拉伸强度上限解的新公式。通过对实测的砂岩动态劈裂试验结果的分析,对比了原始的弹性解和得到的上限解间的差别,研究表明砂岩的动态拉伸性能随加载率的变化不明显,随着加载率的提高,动态拉伸强度曲线较平缓,说明砂岩在动态作用下承受拉应力的能力较低,抗拉强度的变化范围较小。同时验证了基于极限分析法的岩石动态抗拉强度公式可以为砂岩的工程应用提供更安全可靠的参考值。

Limit analysis solution of dynamic Brazilian tests

By using the limit analysis upper bound theorem, the elastic solution of dynamic Brazilian tests is optimized. Considering the effects of the radially angled cracks caused by the high-speed impact at contact points of the disk on the dynamic tensile strength, a new formula for computing the upper bound solution of the limit dynamic tensile strength is obtained. The original elastic solution and new upper bound solution are discussed by analyzing the dynamic tensile results of sandstone. The research shows that the dynamic tensile properties of sandstone do not change significantly with the loading rate. With the increase of the loading rate, the curve of dynamic tensile strength is relatively flat. The upper bound solution offers a more secure and reliable reference value for the use of sandstone rock mass.