Stability Evaluation Of Consequent Bedding Rock Slopes Based On Displacement Information

The stability of consequent bedding rock slope is one of the difficult problems in engineering construction. Because of the stratiform property, the stability of consequent bedding rock slopes are mainly affected by the shear strength and geometrical morphology of weak structure plane (rock layer surface). To evaluate the stability of consequent bedding rock slope, the process of slope from safety to failure condition is simulated by FLAC3D strength reduction method aiming at consequent bedding rock slope (refer to thin layer soft bedding rock slope) in this thesis. The deformation process and stability of slope are researched, preliminary gaining some relations between displacement alternate form and stability of consequent bedding rock slope.In this thesis, the consequent bedding rock slope is classified by lithology, geometric composition of its structure body and weak structure plane. Three common failure models and instability mechanism are researched. The thinking is put forward that the relationship between deformation evolution and slope stability is researched in different sort.It is based on built-in ubiquitous joints model in FLAC3D, that the whole process of slope from safety to failure status is simulated by strength reduction method. The safety factor and the slope deformation alternate process conditions are gained by calculating the different working conditions, which are composited by different slope heights, slope ratios and rock formation dip angles. The consistency between displacement saltation criterion based on displacement tending to infinity and numerical calculation non-convergence criterion is put forward by comparing the consequents of safety factor, which are calculated by the two upper criterions.The geometrical parameters (refer to slope height, slope ratio and rock formation dip angle) are analyzed, which affect stability of consequent bedding rock slope. It indicates that the stability is monotone decreasing with the increasing of slope height and slope ratio, stability is first decreasing then increasing with the increasing of rock formation dip angle. When the ratio of rock formation dip angle and slope angle (arc tangent of slope ratio) is nearby0.5, the stability is worst, which is gained by the numerical calculation strength parameterThree failure models, sliding tension cracking, consequent sliding and sliding bending, are got by researching the failure state of consequent bedding rock slope. The failure processes of three failure models are analyzed from stress-train alternate status and macroscopical deformation. Sliding zone and pulling crack zone gradually rupture is put forward when the slope is failure by analyzing the deformation status.The displacement alternate process of key monitoring point in consequent bedding rock slope is divided into three stage, elastic stage, elastic-plastic stage and failure stage, by analyzing the deformation evolution. The differences between before and after the slope failure are got by analyzing the spatial distribution rule of displacement under three different typical failure models and two transitional stage failure models. Stability of consequent bedding rock slope is evaluated by the stage of displacement alternate, which is got by analyzing the displacement alternate process of key monitoring point and spatial displacement distribution status and suggestion value of safety factors when whole displacements are consistency.