The Model Test And Numerical Simulation Analysis Of Bank Collapsing

Bank collapse is an interdisciplinary research subject,and it has not been well solved at present because of the lack of interdisciplinary comprehensive research.We study the bank collapse mechanism in order to enrich the content of disciplines.The research has important theoretical value.Depends on the bank collapse harnessing engineering of He Yue Continent,it reveals the collapse evolution through model test,numerical simulation and theoretical analysis.It puts forward the preliminary understanding of the erosion mechanisms and the theoretical discussion.It adopted the indoor model test to analyze the law of pore water pressure,earth pressure and the displacement by the different combination of underground water level and the water level before the slope.The results show that slope has experienced the process water erodes,crack development and the whole bank collapse from stabilization to slide.In the process of collapse,the pore water pressure remained stable.Earth pressure value breaks,however,and it has certain rising trend or waving before the mutation.The slopes are prone to collapse while underground water level is stable but the river is higher,or the stable river but higher underground water level.In the process of falling water before slope,the underground water level is hysteretic.In the process of the fourth working condition that water levels falling,it founds that the change of water level is hysteretic and the unsteady seepage begins to form.It adopted the numerical simulation to analyze the slope stability problem in the process of water levels falling considering the fluid-solid coupling and the strength reduction method.The results show that the slope stability gradually reduces until the instability and failure because the low stress area(<130kPa)of slope surface increases gradually in the range of water level fluctuation.Rapid drawdown is one of the most dangerous working condition.The lateral static water pressure to balance the saturated soil decreases rapidly when the water level falling fast.Pore water pressure doesn't fully dissipate because of the hysteretic nature of the underground water level.At the same time,seepage pressure pointing to outside appeared so that it go against the bank slope stability.Therefore,it's more need to guard against bank collapse in the plentiful.In addition,it's not only to monitor the change of displacement,and slope surface stress monitoring analysis is necessary.Finally,it provides a new way of thinking for the further research.