铁路堤坝稳定性分析方法

Stability Analysis Method for Railway Dyke

研究目的:目前,铁路工程中建造在下倾冲沟上的兼顾拦水及导流作用的堤坝是在水利工程中的碾压式土石坝基础上,进行设计及稳定性计算的,但其所受荷载及稳定性控制工况有别于水坝,相关方面的研究很有限,尚未形成一套成熟的铁路堤坝设计、计算的方法。本文结合工程实例,对建造在下倾冲沟上的堤坝稳定性进行分析。研究结论:(1)基底坡降、接触面粘聚力、摩擦系数对堤坝稳定性影响较大;(2)基底坡度大于5%时不宜直接在地面上填筑堤坝,如有条件应尽量将坝底挖平;(3)堤坝基底长期在水位以下,粘聚力降低,在计算中宜将粘聚力取零值。

Research purposes： At present, the design and stability calculation for the railway dyke in declining gully for water retaining and diversion is on the base of those for the hydraulic rolled - earth dam, but the borne load and stability condition of railway dyke are different from hydraulic dam. As a little research has been done on this field, so a set of mature design and calculation method has not been formed for the railway dyke yet. In this paper, the analyses are made for the stability of one railway dyke built in declining gully. Research conclusions： （ 1 ） The stability of dyke in declining gully is influenced by the lowering base gradient, the cohesion of base contact surface and friction coefficient. （2） It is inappropriate to build a dyke on the ground directly when ditch gradient is more than 5%, and the dyke base should be made flat if possible. （3） It is appropriate to regard the cohesion of base contact surface as zero because the base contact surface is immersed in water for long term to drop the cohesive performance.