不同填土厚度下扶壁式挡土墙应力分布规律与稳定性分析

Stress distribution and stability analysis of buttress retaining wall under different filling thickness

摘要

扶壁式挡土墙能有效阻止填土的不稳定运动，为了得到填土对扶壁式挡土墙承载变形规律的影响，本文针对扶壁式挡土墙在不同填土厚度条件下的变形稳定性进行了研究，探讨了填土厚度对挡土墙墙身位移、结构内力分布的影响规律。研究发现：(1)在填土厚度较低时，挡土墙墙顶处的水平位移随填土量的增加而增大。墙体底部的水平位移随填土量增加持续增大，底部承受的压力增大，存在倾斜风险。(2)分析了挡墙墙身的内力变化，发现随着填土厚度的增加，挡墙所承受的侧向土压力及其内部剪应力亦随之升高。尤其在肋板部分，剪应力在某一位置达到峰值。此外，剪应力分布与挡墙位移模式密切相关，挡墙可能发生转动和平动，导致内部应力重新分布。肋板的设计强度和布置对分散土体压力和减少剪应力集中至关重要。(3)填土厚度增加导致挡墙内部应力水平上升，特别在墙前方地面以下一定位置，应力达到最大值。而基底处的应力则由于地基的分散作用而相对较小。设计时需关注填土厚度变化对挡墙整体力学性能的影响，确保结构在最不利条件下仍具足够稳定性。

Abstract

Buttressed retaining wall can effectively prevent the unstable movement of soil filling. In order to obtain the influence of soil filling on the bearing deformation law of buttressed retaining wall, this paper studies the deformation stability of buttressed retaining wall under different filling thicknesses, and discusses the influence law of the filling thickness on the displacement of the retaining wall and the distribution of internal forces of the structure. The result show that:(1) When the thickness of the filling is low, the horizontal displacement at the top of the retaining wall increases with the increase of the filling amount. The horizontal displacement at the bottom of the wall continues to increase with the increase of the filling amount, and the pressure at the bottom increases, so there is a risk of tilt.(2) The internal force change of the retaining wall is analyzed, and it is found that the lateral earth pressure and internal shear stress of the retaining wall increase with the increase of the filling height. Especially in the rib section, the shear stress reaches a peak at a certain position. In addition, the shear stress distribution is closely related to the displacement mode of the retaining wall, and the retaining wall may rotate and move, resulting in the redistribution of internal stress. The design strength and layout of the floor are very important to disperse the soil pressure and reduce the shear stress concentration.(3) The increase in the thickness of the fill causes the internal stress level of the retaining wall to rise, especially in a certain position below the ground in front of the wall, the stress reaches the maximum value. The stress at the base is relatively small due to the dispersion of the foundation. During the design, it is necessary to pay attention to the influence of the change of fill thickness on the overall mechanical properties of the retaining wall to ensure that the structure is still stable enough under the most unfavorable conditions.

关键词

扶壁式挡土墙 / 数值计算 / 应力分布 / 变形 / 稳定性

Key words

buttress retaining wall / numerical calculation / stress distribution / metamorphosis / stability

Author summay

曹雄伟(1986—), 男, 高级工程师, 学士, 从事工程项目管理及相关研究。E-mail: [e-mail]

基金资助

湖南省重点研发计划(2022SK2082)

国家自然科学基金项目(42277175)