服役期内模块式加筋土挡墙稳定性研究

The Research about the Stability of Reinforced Soil Retaining Wall in Operating Period

摘要: 针对加筋土挡墙在服役期内出现的变形过大甚至失稳问题，本文结合某高速公路实际工程，研究筋带蠕变导致的墙面变形对挡墙稳定性的影响。首先，通过现场监测获得了该挡墙5处典型断面的侧向变形分布特征，发现经过8年的服役，挡土墙的最大侧向位移为13.5 cm，侧向位移/墙高值为0.87%。其次，通过建立现场加筋土挡墙的二维有限元模型，分析了在该变形量下挡墙侧向位移、墙后土压力、筋带应力应变及挡墙整体稳定性。数值结果表明：由于挡墙侧向变形的增大，加筋土挡墙的整体安全系数由竣工时的1.85降低至1.28，存在失稳的危险。因此，有必要对该挡土墙的危险断面采取相应的工程加固措施，并改善挡土墙的防排水结构布置。

Abstract: Reinforced soil retaining wall in the course of deformation often occurs instability, so this paper combines specific engineering to research the effect of reinforcement material creep on the stability of reinforced soil retaining wall. First, the distribution characteristics of lateral deformation of 5 typical sections of the retaining wall are obtained through field monitoring. After 8 years of operation, it is found that the maximum lateral displacement of retaining wall is 13.5 cm, and the lateral displacement/wall height is 0.87%. Secondly, through the establishment of a two-dimensional finite element model of reinforced earth retaining wall site, it analyzes of lateral deformation of retaining wall, the earth pressure behind the wall, stress and strain of reinforcement and overall stability of retaining wall under the deformation. Numerical results show: because of the increase of lateral deformation of retaining wall, the overall safety factor of reinforced retaining wall is reduced from 1.85 to 1.28 at the time of completion, and it exists risk of instability. Therefore, it is necessary to take the corresponding reinforcement measures for the dangerous section of the retaining wall, and improve the drainage structure of retaining wall.