- 摘 要
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楊帆1，李紅2
（1 南京城鎮(zhèn)建設設計咨詢公司， 南京 210036； 2 南京市長江河道管理處， 南京 210000）
［摘要］軟土層的分布對于基坑圍護結構水平位移、坑底隆起變形、地表沉降等會產生重要影響。通過數(shù)值模擬的方法研究軟土層位于不同深度時對基坑變形和穩(wěn)定性的影響。分析表明，當軟土層位于坑底位置時，圍護樁的水平位移會明顯增加；當軟土層位于圍護樁底時，對圍護樁的影響較小。當軟土層位于坑底時，坑底表現(xiàn)出塑性隆起的特征、回彈變形量大。隨著軟土層埋深的增加，地表沉降量明顯增大；當軟土層位于坑底時，地表沉降達到最大值，而且地表最大沉降與圍護結構水平位移呈現(xiàn)出明顯的相關性。綜合各種計算結果，當軟土層的埋深處于基坑底部至圍護結構底端這一范圍時，對基坑各方面的影響最不利。
［關鍵詞］基坑開挖； 軟土層分布； 圍護結構； 地表沉降
中圖分類號： TU433 文獻標識碼： A文章編號： 1002-848X(2015)S2-0143-05
作者簡介：楊帆，碩士，高工，一級注冊結構工程師，Email：yangf@ctarch.cn。
Study on the influence of soft soil distribution to the deformation and stability of
excavation under cantilever deformation mode
Yang Fan1, Li Hong2
(1 Nanjing City-Town Architecture Design & Consultants Co., Ltd., Nanjing 210036, China；
2 Nanjing Yangtze River Channel Management, Nanjing 210000, China)
Abstract: The horizontal displacement of guard structure, the heave at bottom and ground settlement is greatly influenced by the distribution of soft soil. The influence of soft soil location to the deformation and stability of excavation is studied through numerical simulation. Result shows that the horizontal displacement of guard pile increases obviously when soft soil is at bottom. The characteristic of bottom deformation is plastic heave, and the rebound deformation is obvious when soft soil locates at bottom of excavation. With the buried depth of soft soil increases, the ground surface settlement increases greatly, and the maximum settlement appears when the location of soft soil is at bottom of excavation. The maximum ground settlement is correlated to the maximum horizontal displacement of guard pile. In summary, when the buried depth of soft soil is within the range between the bottom of excavation and the bottom of guard pile, the excavation is in unfavorable situation.
Keywords: excavation; distribution of soft soil; guard structure; ground surface settlement
