合肥工业大学校徽 合肥工业大学学报自科版

导航菜单

软土地区考虑坑内土体强度的狭窄基坑抗隆起稳定性研究

Study on anti-uplift stability of narrow foundation pit considering soil plug strength in soft soil area

期刊信息

合肥工业大学(自然科学版),2025年8月,第48卷第8期:1125-1131

DOI: 10.3969/j.issn.1003-5060.2025.08.018

作者信息

李庭平 $ ^{1} $,谢晓蕾 $ ^{2} $,李明广 $ ^{2} $

(1. 上海市城市建设设计研究总院(集团)有限公司,上海 200125;2. 上海交通大学土木工程系,上海 200240)

摘要和关键词

摘要: 文章以深厚软土地区狭窄基坑施工为背景,针对目前应用Prandtl计算式验算抗隆起稳定系数无法考虑基底以上土体强度以及无法体现基坑宽度影响的问题,依据极限平衡思想,推导出修正的抗隆起稳定系数计算方法。该方法依据狭窄基坑尺寸和地层土性划分具有不同破坏滑裂面的基坑类型,继而推导得到考虑坑内土体抗剪强度的抗隆起稳定系数计算式;然后使用强度折减法对抗隆起稳定性的影响因素进行对比分析,明确滑裂面假设的合理性和计算方法的实用性。结果表明,该方法能较好地反映基坑宽度变窄对抗隆起稳定性的有利影响,能为基坑优化设计提供一定指导,但也有待于进一步实践验证。

关键词: 狭窄基坑;抗隆起稳定性;宽度影响;Prandtl公式;强度折减法

Authors

LI Tingping $ ^{1} $, XIE Xiaolei $ ^{2} $, LI Mingguang $ ^{2} $

(Group) Co., Ltd., Shanghai 200125, China; 2. Department of Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China)

Abstract and Keywords

Abstract: Taking the narrow foundation pit construction in deep soft soil area as the background, in view of the fact that the strength of soil above the wall bottom and the influence of structural width cannot be considered in the current application of Prandtl calculation formula for checking the anti-uplift stability coefficient, a modified calculation method of anti-uplift stability coefficient is derived according to the idea of limit equilibrium. This method divides the types of narrow foundation pit with different failure slip surfaces according to the size of narrow foundation pit and the soil properties of formation, and then deduces the calculation formula of anti-uplift stability coefficient considering the shear strength of soil in the pit. Then the strength reduction method is used to compare and analyze the factors influencing anti-uplift stability with the method in this paper, and the rationality of the slip surface assumption and the practicability of the calculation method in this paper are clarified. The results show that this method can better reflect the beneficial effect of the narrowed width of the narrow foundation pit on the stability against uplift, and can provide guidance for the optimal design of the narrow foundation pit, which also needs further research and verification.

Keywords: narrow foundation pit; anti-uplift stability; influence of width; Prandtl formula; strength reduction method

基金信息

国家自然科学基金资助项目(41977216)

个人中心