预应力加筋土挡墙变形性能研究

Deformation performance of pre-stressed reinforced earth retaining wall

采用有限差分数值方法研究预应力加筋土挡墙的侧向变形和沉降规律。填料采用双曲线型塑性硬化本构模型,计算过程中考虑填筑和压实过程,采用模型试验的结果验证了数值方法。针对填料的密实度、桥台基础边缘距墙面板距离、预应力筋的轴向刚度建立分析工况。研究结果表明:顶部荷载作用下,预应力挡墙的墙面板位移、顶部沉降均比未施加预拉力的挡墙明显减小;填料的密实度和桥台基础边缘距墙面板的距离对墙面侧向位移影响最大;提高预应力筋的轴向刚度有利于减小挡墙的变形。

The finite difference method was used to study the lateral deformation and settlement law of pre-stressed reinforced earth retaining walls.Backfill soil was simulated by Plastic Hardening(PH)model with a hyperbolic stress-strain relationship.The filling and compaction process was considered in the numerical simulations which were verified by the results of model tests.Analysis cases were established according to the backfill compactness,the distance from the abutment base edge to the wall panel and the axial stiffness of pre-stressed bar.Results show that the displacement of the wall panel and the top settlement of the prestressed retaining wall under surcharge load were significantly smaller than those without pretension.The backfill compactness and the distance from the abutment base edge to the wall panel have the greatest influence on the lateral displacement of the wall.Increasing the axial stiffness of prestressed bars is beneficial to reduce the deformation of the retaining wall.