An Analysis on Displacement of Diaphram Wall in Deep Excavation Using PLAXIS-Kaohusing Xiaogang Construction Engineering

[[abstract]]連續壁為都市中深開挖常用之擋土設施，而基於都市中基地狹小與經濟、施工考量，常局部搭配微型樁以降低損鄰發生機會。而微型樁是利用不同配置與土體結合，形成一阻絕牆以貫穿可能的滑動面，增加可發生破壞區域土體之抗剪力，減少其剪應力降低土體變形以保護開挖面外之建物。 本研究利用位於高雄地區的深開挖工程 (開挖深度約22m，連續壁厚1 2m，深40m，其中西側緊鄰地上七樓地下一樓的建物，利用兩排交錯配置之微型樁保護)，連續壁開挖期間之監測紀錄，探討以有限元素程式PLAXIS模擬分析微型樁影響之可行性，結果顯示在採用合適的土壤參數及合理之邊界條件及初始條件下，PLAXIS 有限元素程式可合理預測微型樁對擋土牆變形的影響。[[abstract]]In urban area the diaphragm wall is often used as a retaining structure in deep excavation and micro-pile is designed in critical area to avoid damaging the neighboring structure The micro-pile is placed and combined with soil to form a barrier wall and to penetrate the sliding surface in order to protect structures nearby the deep excavation area The monitoring data of a 22m-depth deep excavation nearby a 7F+B1F building case in Kaohsiung is collected in this study The thickness of the diaphragm wall is 1 2m and its depth is 40m Two rows of micro-pile are arranged in a staggered way to protect the building A 2D finite element analysis program PLAXIS 2D is used to simulate the influence on the displacement of the diaphragm wall by using the micro-pile As shown in the results the use of the 2D finite element analysis program can be reasonable to predict the lateral deflection of the diaphragm wall through the adequate soil parameters chosen and the appropriate boundary conditions and the corrected initial condition