软岩巷道变形的混沌研究

试验得出了软质页岩最大屈服应变,对软岩巷道变形进行了监测,用混沌理论研究了软岩巷道变形规律.根据监测数据,分别计算了巷道顶部和侧帮变形的分形维数和最大Lyapunov指数,并用Lyapunov指数法预测了软岩巷道的后期变形.研究结果表明:软岩变形具有混沌特性,混沌理论能较好地反映软岩巷道的变形与破坏特征;用重构相空间方法,能充分揭示软岩巷道变形与能量释放规律,据此可确定二次复喷时间;软岩巷道变形在相空间相邻点的距离以指数形式发展,当岩体变形达到最大屈服应变时便产生破坏,以此便可预测和分析巷道的稳定性.

Research on Chaos of Deformation in Soft Rock Tunnel

Maximum yield strains of soft shale have been gained by the test, and deformations in soft rock tunnel were monitored, as well as the laws of deformation in soft rock tunnel were researched by chaos theory. According to the monitored data, fractal dimensions and maximum Lyapunov exponents of deformation in the tunnel top and lateral wall were calculated respectively, and the later deformations in soft rock tunnel were predicted with Lyapunov exponent. Research results show that the deformations in soft rock tunnd hold the character of chaos, and chaos theory can well embody their characters of deformation and breakage. With the method of reconstructing phase space, the laws of deformations and energy release in soft rock tunnel can be revealed fully, and the reasonable time for secondary ejecting can be determined. During deformation in soft rock tunnel, the distances of near point in phase space develop in a way of exponent, when the deformations of soft rock reach the maximum yield strain of shale, the breakages come forth in tunnel, and the stability of tunnd can be well predicted with this method.