尾矿料的动强度特性试验研究

Experimental Study on Dynamic Strength of Tailing Materials

通过对某尾矿坝料进行固结不排水动力三轴试验。对两种尾矿料在不同围压和固结比应力条件下之动强度、孔隙水压力及轴向应变的变化进行了研究。试验结果表明,在循环振动荷载下,对同一固结比,动剪应力随围压的增大而增大,同一围压下,动剪应力随固结比的增大而增大。孔隙水压力的增长主要发生在振动前期,固结比对孔隙水压力的增长影响明显,同时试验结果可用双曲线较好地进行拟合。在低固结比条件下,轴向应变1%附近存在应变突增点。试验研究成果为该坝的动力稳定性分析提供了参数,也为后续尾矿料的动力特性研究提供参考。

The consolidated undrained cyclic triaxial shear tests are performed on samples from two different tailing materials. The shear strength, pore water pressures and the axial strain parameters of these samples were comparatively studied under va rious confining pressures as well as consolidation stress ratios. The results indicate that, under the cyclic loading conditions, if a consolidation ratio remains constant, the dynamic shear stress increases with the confining pressure. Under a constant confi ning pressure, the dynamic shear stress increases with the consolidation ratio. A rapid increase of the pore water pressure oc curs at the early stage of the cyclic loading and the consolidation ratio has an obvious effect on the pore water pressure increase. The results also show that a parabola curve can reasonably fit the test results. Under a low consolidation ratio, a rapid strain change is observed at an axial strain of 1%.