以3D有限元素法模擬擋土壁破壞案例之研究－錨錠式鋼板樁工法

Simulation of Failure Anchored Sheet Pile Walls Case Based on 3D Finite Element Method

李景亮(Jin-Lian Lee) ； 張哲睿(Che-Jui Chang) ； 洪浚雄(Jiun-Shiung Hung)

《中華建築技術學刊》 9卷1期 (2012/12) Pp. 77-85

https://doi.org/10.30021/JBCT.201212.0007

摘要

擋土壁設計應依據其功能要求、行為機制、基地地形地質與容許變位量等，充分檢討整體穩定性，以確保並提升牆體結構安全性及周邊設施正常營運。以碼頭興建工程為例，擋土壁體必須承受本身土壓力與海洋不確定之水壓力因素，在施工過程中常產生碼頭法線偏移問題。其發生原因、破壞狀況與預防是一個值得探討的課題。本研究以三維非線性有限元素法分析擋土壁與土壤互制之問題，模擬某錨綻鋼板樁式碼頭之法線與錨綻鋼板樁同時偏移破壞之發生情形，並將案例模擬結果與調查監測資料比對分析，建構受力變化狀況與分析破壞原因提出預防對策，以提供工程界未來施工及材料還用參考。根據程式模擬結果得知造成法線岸壁冠牆鋼板樁變位過大之主因係拉索斷裂，海中法線岸壁冠牆鋼板樁底基礎超挖2.1m時，鋼板樁及拉索應力仍在容許應力內，故拉索斷裂並非容許應力不足造成，而應為材質瑕疵造成。

關鍵字

三維有限元素法 ； 錨綻式鋼板樁

並列摘要

The retaining wall, designed to achieve the purpose of self function request, behavior mechanism, site, geology, allowable displacement, full stability, serves to promote structure security and its regular peripheral facility function. Take the wharf constructing project for example, the retaining wall needs to withstand the earth pressure and the indefinite hydraulic pressure. The case of wharf displacement during construction happens frequently, of which the root causes, destructive situations, and the preventive measures are worth exploring. With 3D-nonlinear finite element analysis method, this research discovers the interaction between retaining wall and soil, stimulates the phenomenon between wharf crow line and wharf displacement caused by a certain anchorage steel pile, analyzes the comparison between the simulation results and investigation data, offers preventive strategies for the construction stress change and destruction, and provides preventive cautions and choices of material for the engineering line in future. Based on the formula stimulation result, cable fracture proves to be the principal factor for the huge displacement on crown line along the wharf wall steel pile. When overcut along the steel sheet pile basement 2.1 m, the anchorage cable stress was still in allowable value, Therefore the cause of cable fracture is proved of its poor material quality, not of the allowable stress.

並列關鍵字

3D Finite Element Method ； Anchorage Steel Sheet Pile