Effectiveness and engineering application of outrigger-type diaphragm walls
HU An-feng1, RAO Hang1, 2, YUAN Jing3
(1. Key Laboratory of Soft Soil and Environmental Geotechnical Engineering, Ministry of Education, Zhejiang University, Hangzhou 310058, China; 2. Shanghai Municipal Engineering Design General Institute(Group) Co., Ltd., Shanghai 200092, China;3. Zhejiang Province Institute of Architectural Design and Research, Hangzhou 310006, China)
Abstract: As a technique for protection of adjacent buildings, the outrigger-type diaphragm wall been applied in deep excavation engineering. But the worldwide researches in this area are still relatively scarce until now. In extension project of Hangzhou Huanglong Hotel, outrigger-type diaphragm walls are adopted to solve the problem of insufficient rock-socketed depth. And thus the rock-socketed depth of support structures in intermediary weathered rock is ensured. Moreover, the construction difficulty is reduced. Good social and economic benefits are gained. Based on the Huanglong excavation case, a 3-D finite element model is presented to simulate the behavior of outrigger-type diaphragm walls by using the software ABAQUS. The behavior of soil is assumed to conform to the modified Cam-clay model, and the actual construction sequence is simulated. The numerical results and monitoring data in the excavation of lateral displacement are compared. The reasonable stiffness of the section steel in the outrigger-type diaphragm walls is also analyzed.
[1] 黄 琦, 夏继君. 带支腿的地下连续墙的设计与施工[J]. 建筑施工, 2001, 22(1): 7–9. (HUANG Qi, XIA Ji-jun. Design and construction of leg-support diaphragm wall[J]. Building Construction, 2001, 22(1): 7–9. (in Chinese)) [2] 袁 静, 刘兴旺, 曹国强. 带支腿地下连续墙设计和应用[J]. 岩土工程学报, 2010, 32(增刊1): 245–248. (YUAN Jing, LIU Xing-wang, CAO Guo-qiang. Design and application of leg-supported diaphragm walls[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(S1): 245–248. (in Chinese))