贴坡式玄武岩纤维石笼河道护坡的离散元分析

Discrete Element Analysis of River Slope Protection with Basalt Fiber Gabion

针对盐碱土地区河道边坡存在不利于植物生长且易腐蚀混凝土和筋材的问题,提出一种采用玄武岩纤维石笼的防护技术。以某苏打盐碱土河道护坡为例,采用颗粒离散元程序PFC2D标定土体和玄武岩纤维石笼的细观参数并建立了离散元计算模型。在考虑渗流作用的情况下,采用颗粒流强度折减法分析了设计洪水位下石笼护坡的稳定性,并与原始边坡进行对比,此外对工程中关注的复合筋受力特征进行研究。结果表明:采用石笼支护后边坡的稳定系数提升了40.9%,坡内土体未发生破坏和滑动,石笼护坡的破坏形态表现为石笼之间的脱开和复合筋受弯脱开,复合筋的拉压应力远低于其允许的强度值。

Aiming at the problem that the river slope in saline soil area is not conducive to plant growth and is easy to corrode concrete and reinforcement,this paper proposes a protection technique using basalt fiber gabion.Taking a soda saline-alkali soil river slope protection as an example,the particle discrete element program PFC2D is used to calibrate the micro-parameters of the soil and basalt fiber gabion,and a discrete element calculation model is established.Considering the effect of seepage,the particle flow strength reduction method is used to analyze the stability of the gabion slope protection under the design flood level and compare it with the original slope.In addition,the stress characteristics of the composite reinforcement that are concerned in the project are studied.The results show that the stability factor of the slope has increased by 40.9%after gabion support is used,the soil in the slope is not damaged and slipped,and the failure mode of the gabion slope protection is shown by the separation between the gabions and the bending and separation of the composite bars.The tensile and compressive stress of the composite bar is much lower than its allowable strength value.