The Stability Study on Bottom Ground Improving under Excavation

• Main Authors: Chih-Hao Yen, 顏志豪
• Other Authors: Tien-Kuen Huang
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/82066718120289027430

碩士 === 國立中興大學 === 土木工程學系所 === 105 === There are densely populated and land limited in Taiwan area. The land acquirement is getting more difficult with the rapid development of urbanization. More underground excavation engineering is widely carried out. The stability of retaining structure and the engineering properties of underground excavation with different depth of improvement of bottom soft soil layers is worth studying further in order to provide the references of construction and design for relevant engineering agencies. This study aims at the related mechanical behavior and engineering properties of underground excavation examples of 10m excavated depth supported with steel sheet-pile and two layers of internal horizontal support under different depth of improvement of bottom soft soil layers using Plaxis 2D finite element program. From the analyzed results, it indicates that: (1). the outcomes are found more effective in the maximum horizontal displacement of steel sheet-pile with improvement of bottom soft soil layers, the decreasing rate is 35.3% for 3m depth of improvement compared with that without improvement (17.73cm11.43cm) and 86%(17.73cm2.47cm) for 9m depth of improvement. (2). the maximum shear of steel sheet-pile and axial forces of the second layer of horizontal support are decreased in the rates of 54.8% and 59% (168.7 kN/m76.31 kN/m, 188.39 kN77.32 kN) respectively for 9m depth of improvement compared with those without improvement. The proper effectiveness is discovered. (3). the heaving quantity and the maximum moment of steel sheet-pile are decreased about in the rates of 45% for 9m depth of improvement compared with those without improvement. (4). the maximum axial force of the first layer of horizontal support seems little relevance to the improvement of bottom soft soil layers. This is attributed that the first layer of horizontal support is far away from bottom soft soil layers.