深基坑土钉支护设计——以博爱路下穿车行隧道施工为例

Deep Base Soil Nail Supporting Design:A Case Study of Sub-Pavement Tunnel's Construction in Bo'ai Road

土钉支护施工方案具有材料用量和工程量少;施工速度快,工期短;施工设备轻便,操作方法简单;对场地土层的适应性强;结构轻巧,柔性大,有很好的延性;安全可靠;成本低等优点,具有很强的适用价值。本文以广东省中山市博爱路车行下穿隧道深基坑开挖采用土钉支护施工方案的比选确定过程为主线,阐述如何根据土质的物理力学指标及钻孔地质条件、支护几何形式,进行土钉强度、长度验算,分析土钉支护的内、外部稳定性。

Soil nail supporting enjoys advantages such as less materials, high efficiency, light construction equipment, simple operation, strong adaptability to space soil layer, good flexibility and tensility, total reliability, and low cost, etc., which promises a potential great market. This paper takes as an example sub-pavement tunnel＇s deep base excavation in Zhongshan by adopting soil nail supporting, discussing calculation of the strength and length of soil nail, and analyzing the internal and external stability by soil nail supporting according to physical mechanics index of soil, nature of soil in terms of drilling, and supporting geometric forms.