不同墙趾约束条件下模块式加筋土挡墙离心模型试验

陈建峰; 张琬

doi:10.11779/CJGE201810018

不同墙趾约束条件下模块式加筋土挡墙离心模型试验 English Version

陈建峰,
张琬

同济大学地下建筑与工程系,上海 200092

基金项目: 国家自然科学基金项目（41772289,41072200）

详细信息

作者简介:
陈建峰(1972- ),男,浙江余姚人,教授,工学博士,主要从事加筋土结构与边坡支护、岩体力学与工程等方面的教学与研究工作。E-mail: jf_chen@tongji.edu.cn。

中图分类号: TU476.4
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出版历程
- 收稿日期: 2017-08-14
- 发布日期: 2018-10-24

Centrifuge modeling on reinforced soil segmental retaining walls under different toe restraint conditions

Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China

摘要

摘要: 开展了墙趾正常约束、仅对模块-基座界面作光滑处理、仅对基座-地基界面作光滑处理,以及对基座-地基界面作光滑处理且将基座前方土体挖除这4组不同墙趾约束条件的模块式加筋土挡墙离心模型试验,以研究工作应力下墙趾约束条件对挡墙内部稳定性的影响。研究结果表明,墙趾约束条件对模块式加筋土挡墙内部稳定性影响显著;对模块-基座界面作光滑处理的挡墙,其底层模块沿该界面滑移,挡墙中下部的墙面水平位移和筋材应变明显增大,筋材连接力沿墙高呈三角形分布;对基座-地基界面作光滑处理的挡墙,基座前方地基土仍可给基座提供足够的墙趾约束作用,挡墙内部稳定性同墙趾正常约束情况;对于基座-地基界面作光滑处理后又将基座前方土体挖除这种模拟墙趾受到冲刷的挡墙,其基座沿该界面滑移,挡墙中下部的墙面水平位移和筋材应变显著增大,筋材连接力接近极限状态AASHTO法计算的筋材最大拉力,但挡墙仍能保持稳定;在墙趾可能受到冲刷的极端情况下,挡墙在设计上不应考虑墙趾的约束作用,而对于正常服役状态的挡墙,可采用考虑墙趾约束作用的K-刚度法进行挡墙内部稳定性的计算。
- 加筋土 /
- 模块式挡墙 /
- 离心模型试验 /
- 墙趾约束 /
- 内部稳定性
Abstract: The centrifugal model tests are performed on four reinforced soil segmental retaining walls under different toe restraint conditions, which are normal toe restraint, smoothing the block-pad interface, smoothing the pad-foundation interface, smoothing the pad-foundation interface and then excavating the foundation soils in the front of the leveling pad. The influences of the toe restraint condition on the internal stability of reinforced segmental wall under working stress are discussed. The test results show that the toe restraint conditions significantly affect the internal stability of reinforced soil segmental walls. For the wall that the block-pad interface is smoothed, the bottom block slides along the block-pad interface, which leads to an obvious increase in the horizontal displacements and reinforcement strains within the middle and lower parts of the wall and a triangular distribution with height of connection loads between reinforcements and facing. For the wall with the pad-foundation interface smoothed, the foundation soils in the front of leveling pad can provide the pad with enough restraint, thus the internal stability of the wall is the same as that under the normal toe restraint. The purpose of smoothing the pad-foundation interface and then excavating the foundation soils in the front of the leveling pad is to simulate the condition that the toe is scoured. In such condition, the pad slides along its interface with the foundation soils, the facing displacements and the reinforcement strains within the middle and bottom parts of the wall increase significantly, and the connection loads in reinforcements are close to the maximum reinforcement loads under the limit state calculated by the AASHTO method, but the wall still remains stable. In the extreme situation where the toe is eroded by scouring, the effect of toe constraint should not be considered in the design of the reinforced soil segmental retaining walls. For the walls under working stress, the reinforcement loads can be calculated using the K-stiffness method with consideration of the toe restraint effects.
- reinforced soil /
- segmental retaining wall /
- centrifugal model test /
- toe restraint /
- internal stability

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参考文献(16)

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