Optimization Design And Application Of Debris Flow Flexible Network

On the basis of the traditional flexible-net dam,a new type of flexible net is designed.Compared with the traditional flexible-net dam,the flexible-net protection increases the number of layers,and expands the scope of application.The reasonable layer spacing is designed to make the accumulation body reach the ideal stable state.On the basis of the traditional flexible-net dam,a new type of flexible net is designed.Compared with the traditional flexible-net dam,the flexible-net protection increases the number of layers,and expands the scope of application.The reasonable layer spacing is designed to make the accumulation body reach the ideal stable state.In order to study the effect of the flexible net,a series of flume simulation experiments and numerical simulation of the accumulation body are carried out;and the movement characteristics of debris flow and numerical simulation are analyzed in Xiejiagou,a slag accumulation point in a mining area of Qinling Mountains.According to the results,the protection design of the flexible net is carried out to provide a reference for the protection of debris flow.We find some conclusions in experiments,numerical simulation and application.(1)Under certain conditions,the flexible-net protection can carry out repeated experiments.The error has little effect on the results,and it has a good effect of blocking the coarse and arranging the fine.(2)In the experiment of determining the scope of application of flexible net protection,the analysis of the effect of volume weight on sand blocking of flexible net is mainly studied.With the increase of volume weight,the particles larger than the protective mesh of flexible net can be better blocked,and the effect of coarse blocking function is good;while the particles smaller than the protective mesh of flexible net,with the increase of volume weight,the function of fine discharging decreases,and the pores filled with large particles are filled after being blocked The volume weight is less than 2.2t/m~3,and the protective effect of flexible network is more significant than that of coarse and fine.(3)At the same time,the change of the back silting shape before the protection of the flexible-net is studied,and the characteristics of the back silting longitudinal slope curve under different layer spacing and different bulk density are obtained.The curve does not decrease nonlinearly,but first increases and then decreases.For the same volume weight,with the increase of layer spacing,the thickness of silting longitudinal slope increases;for the same layer spacing,with the increase of unit weight,the thickness of silting increases.The accumulation between the flexible network protections increase of the ratio of 1:500,then the numerical simulation analysis of the accumulation shows that with the increase of layer spacing,the stability of accumulation body is enhanced.(4)This paper analyzes the application of flexible-net protection to Xiejiagou,the slag accumulation point in Qinling mining area.Based on the calculation of debris flow movement characteristics in the downstream of gully,it is assumed that the peak flow of clear water in the once-in-a-century precipitation is 8.1 m~3/s,and the peak flow of debris flow is 12.74 m~3/s;when the peak flow lasts 40 minutes,the total amount of one-time flow is 6176 m~3,and the amount of one-time solid flushing is 1853 m~3;the average flow velocity of debris flow is 4.9 m/s,and the impact force reaches 44.3 KN,the maximum punching height is 1.96 m.At the same time,using numerical simulation of debris flow movement process,flow velocity and mud depth change.Based on these data,flexible network protection are designed and applied.