| 摘要: |
| 地下连续墙基础是一种埋深相对较浅的摩擦性基础，在巨厚层黄土地基中具有广阔应用前景。为研究大厚度黄土场地闭合型地下连续墙竖向抗压承载特性，选用石英粉、砂、膨润土和石膏制备黄土相似材料，模拟天然原状黄土，选用有机玻璃制作模型墙，进行室内缩尺模型试验，研究地下连续墙基础荷载传递机理与竖向抗压承载特性。结果表明：地下连续墙基础在竖向荷载作用下的荷载-沉降关系曲线呈陡降型，存在显著破坏特征点。地下连续墙基础竖向承载力由内墙侧摩阻力、外墙侧摩阻力、承台土反力和墙端阻力共同组成。地下连续墙竖向承载力达到极限时，总侧摩阻力占62%，为端承摩擦型基础，芯土的存在可有效减小地下连续墙基础沉降。试验结果可为大厚度黄土场地地下连续墙基础的选型设计提供参考。 |
| 关键词: 基础工程 承载特性 模型试验 地下连续墙 黄土 |
| DOI： |
| 分类号:TU41 |
| 基金项目:国家自然科学基金资助项目（41402252，41662017，41562014） |
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| Experimental study on vertical compressive bearing capacity of underground diaphragm wall foundation in loess area |
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LI Jiandong1, WANG Xu1, ZHANG Yanjie1, LI Fan2, LI Sheng1, LUO Haoyang1
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1.School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou;2.Shaanxi College of Communication Technology, Xi'an
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| Abstract: |
| The foundation of the underground diaphragm wall is a kind of frictional foundation with relatively shallow buried depth, which has a wide application prospects in the foundation with huge thick loess layer. In order to study the vertical compressive bearing characteristics of the underground closed diaphragm wall in the loess foundation with huge thick loess layer, the quartz powder, sand, bentonite and gypsum are chosen to prepare as the similar materials of loess, which simulate the natural undisturbed loess. And this model wall is made of the organic glass. Indoor scale model testing is carried out to analyze the load transfer mechanism and the vertical compression bearing capacity of the underground diaphragm wall foundation. The testing and analysis results show that the load settlement relationship curves of the underground diaphragm wall under the vertical loads belong to the type of steep fall, and there exist some significant failure points. The vertical bearing capacity of the underground diaphragm wall is composed of inner shaft resistance, outer shaft resistance, toe resistance and soil resistance under the cap, and the four kinds of the resistance are asynchronous. When the vertical bearing capacity of the underground diaphragm wall reaches its limit, the load sharing ratio of the total shaft resistance is 62%, and the underground diaphragm wall belongs to the end bearing friction foundation. The existence of the core soil can effectively reduce the settlement of the underground diaphragm wall foundation. The testing results can provide a technical reference for the type selection and design of the underground diaphragm wall foundation at large thickness loess sites. |
| Key words: foundation engineering bearing capacity model test underground diaphragm wall loess |
