深開挖中地中壁之三維分析

Three Dimensional Analysis on Cross Walls in Deep Excavation

梁信盈(Sin-Ying Liang)

指導教授 ： 陳水龍

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2010年)

摘要

地中壁之行為屬於三向度問題，但是目前工程界最常採用之分析法為單向度彈塑性樑分析法（例如RIDO等程式），較無法正確的模擬地中壁之三向度效應。本研究採用三向度數值分析軟體Plaxis 3D Foundation，進行地中壁實際案例之分析，觀測連續壁側向變位量，與實際案例之監測結果進行比對，並考慮地中壁之開挖方式、設置數量及貫入深度等，繪出側向變位量及應力大小之正規化圖表，為設計者提供更準確之參考資訊，以達到最佳化與更具經濟性的地中壁配置。
本研究利用由PLAXIS BV 於2004發行之數值模擬軟體Plaxis 3D Foundation 進行數值模擬，主要探討地中壁施作後，在開挖過程中、單元尺寸差異對連續壁變位之影響與結果，首先針對案例之監測資料，根據參數的經驗公式與結構體折減強度進行驗證，爾後改變案例中之地中壁厚度、數量、貫入開挖面深度和開挖面積長寬比等進行討論。本研究中，以林雅雯（1998）於台北市長安西路上實際監測案例，進行地中壁監測研究分析，藉由改變地中壁尺寸，以探討在開挖過程中對連續壁之影響。

關鍵字

地中壁 ； 扶壁 ； 連續壁 ； T型界面 ； 扶壁長度 ； 扶壁間距 ； 壁體變位量

並列摘要

The behavior of diaphragm walls is a 3-dimentional issue. However, it is often analyzed with 1-dimensional elasto-plastic beam analysis method (e.g. with RIDO) in engineering society, and the result is unable to simulate correct behavior of a 3D diaphragm wall. In this study, the 3D numeric analysis program, Plaxis 3D Foundation was introduced for the analysis of diaphragm wall in a practical case. The lateral displacements of diaphragm wall were produced and compared with the monitoring data of the selected case. Normalized lateral displacement vs. stress diagrams were plotted with the consideration of how the diaphragm walls were excavated, how many wall units there were and the penetration depth of these units. The plots may serve as more accurate reference material for designer to achieve optimized designs and more economic layout of diaphragm walls.
Plaxis 3D Foundation, a numeric analysis program developed by PLAXIS BV in 2004, was used for numeric simulation. The investigation focused on the influence of the wall unit size to the lateral displacement of diaphragm wall and its result during the excavation of site after the diaphragm walls were installed. First, the monitoring data of the selected case was verified using empirical equation of parameters and factored structural strength, and then the thickness and number of diaphragm walls, penetration depth below excavation level and L/W ratio of excavation coverage were changed for further investigation. The practical monitoring case of Lin, Ya-Wen (1998) on Chang-An West Road, Taipei City was selected for research and analysis of diaphragm monitoring. The impact of diaphragm wall size changes to the wall bodies during excavation was studies.

並列關鍵字

buttress ； cross wall ； T section interface ； buttress length ； buttress spacing ； diaphragm wall displacement

參考文獻

[14] 吳文隆、朱振宏(2008)，國內深開挖工程探討，技師月刊49，2008，06，地下開挖施工專輯。

[21] 李煜舲（1997），擋土牆排水之數值模擬與分析，地工技術，第85期，P51-60。

[27] 邱志榮(2007)，三重-蘆洲地區深開挖參數研究，碩士論文，國立台北科技大學土木與防災研究所，台北。

[33] 張吉佐、陳坤泉，設計參數對深開挖檔土支撐支敏感度評估，地工技術，第76 期，1999，第17-24 頁。

[51] 冀樹勇、陳錦清、王建智(1999)，台北RIDO 程式之最佳化參數之探討，地工技術第75 期，pp.61-76。