反倾层状岩体倾倒变形发育深度模型的计算分析

为分析反倾岩质边坡弯曲倾倒破坏机理,通过对反倾层状岩体的物理力学解析及悬臂梁极限平衡分析模型的优化,开展反倾层状岩体变形发育深度计算研究。基于流变理论,采用广义开尔文流变模型,以变形发育极限位置处零应变作为发育深度的界定标准,获取了反倾层状倾倒变形体的发育深度。进而,将两种方法推导出来的计算式进行工程实例分析,并与前人的研究成果进行对比分析,探讨其工程实际应用价值。实例计算表明:优化下的悬臂梁模型比广义开尔文流变模型计算的发育深度更接近实际情况;反倾层状边坡倾倒变形破坏发展演化的四个阶段为初始弯曲变形阶段、累计弯曲变形阶段、板裂体折断破裂阶段、破坏阶段。研究成果对反倾层状岩质边坡整体稳定性判别及失稳规模预测具有一定理论意义和参考价值。

Calculation and analysis on model for toppling deformation developing depth of anti-dip stratified rockmass

In order to analyze the flexural toppling failure mechanism of anti-dip rock slope，the calculation and analysis on the topplingdeformation developing depth of anti-dip stratified rockmass are made herein through the physical mechanics analysis on the anti-dip stratified rockmass and the optimization from the relevant cantilever beam limit equilibrium analysis model. Based on rheological theory，the developing depth of the anti-dip stratified toppling deformation mass is obtained with the generalized Kelvin rheological model by taking the zero-strain at the ultimate location of the deformation development as the definitioncriterion for the developing depth. Moreover，the calculating formulas derived from both the methods are analyzed through the relevant engineering cases，and then compared with the results from the studies made by the predecessors concerned，so as to discuss the actual engineering application values. The actual case calculation shows that the calculated developing depth obtained from the optimized cantilever beam model is more close to the actual condition，if it is compared with that from the generalized Kelvin rheological model. Furthermore，it is put forward that the four stages of the developing evolution of the anti-dip stratified rock slope are the initial flexural deformation stage，the accumulated flexural deformation stage，the breaking and cracking stage of platyrockmass and the failure stage. The study result has certain theoretical significance and referential value for distinguishing the integral stability of the anti-dip stratified rock slope and predicting the potential instability scale concerned.