Ballastless track in high-speed railway has strict requirement on post-construction settlement of subgrade, so it's worth to study the influence of lateral displacement of sheet-pile wall on the settlement of subgrade. By using the finite element numerical analysis and combined with field measurement, based on the point of shoulder sheet-pile wall ,making analysis on the changing law of back earth pressure、size and distribution form of additional settlement of subgrade caused by the displacement of wall and creating functional relationship between additional settlement of characteristic part and lateral displacement of wall top through gradually release the lateral displacement of the wall top. Results suggest that: distribution form of the wall back earth pressure along wall cantilever first increases then decreases, the maximum appeared at the top of the wall under 6~7 m, the soil has entered the active state under the site condition. the additional settlement caused by the lateral displacement of the wall top along the subgrade cross-section approximately is alike triangular distribution and its influence scope is about 17.2 m. on the worksite, analytical relationship between lateral displacement of wall top s and settlement of subgrade surface under the rail nearby the pile e is e=0.4s and the additional settlement of subgrade only account for 13% of post-construction settlement permitted.%针对陡坡地段路肩式桩板墙侧向位移对高速铁路无砟轨道路基沉降的影响.采用有限元数值分析并结合现场实测,以某高速铁路无砟轨道陡坡地段路肩式桩板墙工点为原型,通过逐步释放墙顶侧向位移,分析墙背土压力的变化规律;研究由此产生的路基面附加沉降大小及分布形态;建立特征部位处附加沉降与墙顶侧向位移的函数关系.研究结果表明:墙背土压力沿墙背呈先增加后减小的分布形态,最大值出现在墙顶以下6~7 m之间,现场工况条件下墙后土体已进入主动状态;墙顶侧向位移引起的路基面附加沉降沿路基横断面近似呈三角形分布,其影响范围约为17.2 m;墙顶侧向位移与路基面附加沉降基本呈线性关系;现场工点墙顶侧向位移s与近墙钢轨轨下路基面沉降e的解析关系为e=0.4s,工后墙体侧向位移引起的路基面附加沉降仅为工后沉降规范允许值的13%.
展开▼
