路塹橋墩深基礎開挖PLAXIS 3D模擬分析

PLAXIS 3D Modeling of Pier Foundation Excavation at Embankment

鄭郁翰(Yu-Han Zheng)

指導教授 ： 倪至寬

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2014年)

摘要

近年來都市蓬勃發展，尤其桃園地區積極開發且陸續興建重大建設，吸引大量人口就業與居住，造成國道1號行經桃園、中壢、楊梅等精華地段交通壅塞，為紓解桃園路段塞車問題，國道新建工程局（簡稱國工局）辦理「國道1號五股至楊梅段拓寬工程計畫」之新建工程。其中泰山林口路段，因為上邊坡側為地質敏感區域不適開挖，所以在下邊坡處進行橋墩基礎開挖，使用三種不同的開挖擋土工法，分別為型鋼襯板擋土工法、土釘逐階降挖擋土工法與竹削井式擋土工法。
本文針對土釘逐階降挖擋土工法與竹削井式擋土工法，蒐集傾度管原始監測數據，彙整後繪製不同開挖階段之傾度管側向變位及側向變位速率圖形，搭配高速公路裂縫位置，進而研判邊坡潛在滑動面的位置，最後依據傾度管的變位、開挖壁面的穩定性、高速公路裂縫與滑動面的產生以及工期長短，以決定較佳開挖擋土工法。其次，以非線性有限元素法軟體PLAXIS 3D，模擬土釘逐階降挖擋土工法與竹削井式擋土工法之每一階開挖過程，以數值回饋分析結果與現地傾度管變位比對，驗證材料參數適用性，並藉由每階段開挖之位移增量、剪應變增量與塑性圖，研判邊坡潛在滑動面可能之位置。

關鍵字

卵礫石 ； 土釘 ； 有限元素法

並列摘要

In recent years the city is flourishing, especially in the Taoyuan city. Actively developed and continue to build major construction, attract large numbers of people to employment and live. Causing National Highway No. 1, passing through prime locations of traffic congestion, such as Taoyuan, Chungli and Yangmei city. In order to relieve Taoyuan city traffic congestion problem,“Ministry of Transportation and Communications Taiwan Area National Expressway Engineering Bureau”plan to widening National Highway No. 1,from Wugu to Yangmei. The bridge foundation excavation use three different method, such as H-Beam Products with wood excavation retaining method, soil nail with shotcreting excavation retaining method and “Bamboo Cutting”excavation retaining method.
In this research, collect original displacement data of inclination tube of soil nail with shotcreting excavation retaining method and“Bamboo Cutting”excavation retaining method. Drawing lateral displacement and lateral displacement rate curve of each stage of excavation. Combine the turning point of lateral displacement curve and the crack location on the highway. Furthermore judged the sliding surface position of the slope. Finally, according to the lateral displacement of the inclination tube, stability excavation wall, the crack location on the highway, and duration of the work, to determine the preferred excavation retaining method. Secondly, use nonlinear finite element method software PLAXIS 3D, to Simulate each step excavation process of soil nail with shotcreting excavation retaining method and“Bamboo Cutting”excavation retaining method. Use the lateral displacement curve of analysis result to compared with actual lateral displacement of the inclination tube, verify that the suitability of the material parameters. And then, out put the Incremental of displacement, Incremental of shear strain, and plastic point graph. To judge the sliding surface position of the slope.

並列關鍵字

Gravelly Soil ； Soil Nail ； Plaxis 3D

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