基于溶质运移的悬挂防渗墙管涌控制效果

Piping control effect of suspended cut-off wall based on solute transport

利用基于溶质运移思想建立的渗流侵蚀耦合管涌模型,探讨不同贯入比的悬挂式防渗墙的管涌控制效果,通过跟踪堤基孔隙率及液化细颗粒体积分数的演变过程,反映管涌通道的发展过程.研究表明,悬挂式防渗墙对管涌通道的扩展具有非常明显的控制效果,防渗墙的贯入比是决定控制效果的关键因素.当贯入比小于0.7时,防渗墙对孔隙率及液化细颗粒体积分数影响巨大;贯入比越小,孔隙率及液化细颗粒体积分数的增大速度及影响范围越大,即悬挂式防渗墙的贯入比越小,管涌通道扩展速度越快,规模越大.当贯入比大于0.7时,悬挂式防渗墙对孔隙率及液化细颗粒体积分数影响较小,增大贯入比对改善管涌控制效果不明显.

The piping control effect of suspended cut-off wall under different penetration ratios was analyzed by using the seepage erosion coupling piping model based on solute transport. The development of piping channel was described by analyzing the changes of soil porosity and fluidized particles volume fraction. Results indicate that the piping control effect of suspended cut-off wall is very obvious, and the penetration ration of cut-off wall is the main determinant of control effect. When the penetration ratio is smaller than 0. 7, the suspended cut-off wall intensively affects the porosity and the fluidized particles volume fraction. The smaller the penetration is, the larger the increasing velocity of porosity and the fluidized particles volume fraction and the sphere of influence are, i.e. the smaller the penetration is, the faster the piping channel development is. When the penetration ratio is larger than 0.7, the suspended cutoff wall slightly affects the porosity and the fluidized particles volume fraction, and increasing the penetration ratio is not obviously effective for improving the piping control effect.