FANG K,WANG S,LIU N W．Active earth pressure analysis of adjacent foundation pits excavated[J].Journal of Henan Polytechnic University(Natural Science)，doi:10.16186/j.cnki.1673-9787.2024010009

doi:10.16186/j.cnki.1673-9787.2024010009

Received：2024-01-02

Revised：2024-02-25

Online：2024-03-05

Active earth pressure analysis of adjacent foundation pits excavated (Online)

FANG Kai¹,WANG Shuo¹,LIU Nianwu²

( 1.College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,Shandong,China; 2.School of Civil and Architecture,Zhejiang Sci-Tech University,Hangzhou 310018,Zhejiang,China)

Abstract: Objective When adjacent foundation pits are excavated simultaneously, the deformations of both sides of the finite soil between the pits will influence the distribution of earth pressure. The rational analysis and determination of the characteristics of finite soil pressure have become crucial issues in engineering. Methods In order to characterize the soil pressure of finite soil under the condition of adjacent foundation pit excavation, the deformation law of finite soil under the condition of simultaneous excavation of adjacent foundation pits and the influence mechanism of adjacent foundation pit excavation on the development of soil pressure are analyzed by discrete element method. Through the stress analysis of soil elements in different regions, the analysis model of active soil pressure of finite soil in the process of adjacent foundation pit excavation is constructed, and the characteristics of soil pressure of finite soil under different retaining wall displacement conditions are analyzed. Results The results show that the displacement field and slip mode of finite soil are different from those of unilateral foundation pit excavation. Compared with the finite soil under the condition of unilateral foundation pit excavation, the earth pressure on the retaining wall under the condition of simultaneous excavation of adjacent foundation pits is smaller. The difference of earth pressure between the two cases is affected by the aspect ratio of the finite soil and the displacement of the retaining wall. The smaller the aspect ratio of the finite soil, the greater the pressure difference. With the increase of the displacement of the retaining wall, the difference of the earth pressure between the two increases first and then decreases. When the displacement of the retaining wall reaches half of the displacement required for the overall active limit state of the soil, the earth pressure difference reaches the maximum value. Conclusion The method proposed in this paper can better characterize the distribution characteristics of earth pressure under the condition of simultaneous excavation of adjacent foundation pits, and provide theoretical support for the calculation of active earth pressure of limited soil under the influence of displacement of retaining walls on both sides.

Key words: active earth pressure; limited soil mass; adjacent foundation pits; distinct element method