复合土钉墙技术在深圳的应用与发展

复合土钉墙是一种新型的支护结构,在深圳地区基坑工程中得到了广泛应用。文中介绍了复合土钉墙在深圳地区的发展和应用情况,总结了土钉墙 止水帷幕 预应力锚杆、土钉墙 预应力锚杆、土钉墙 微型桩 预应力锚杆、土钉墙 止水帷幕 微型桩 预应力锚杆等四种最常用的复合土钉墙形式,对它们的设计计算方法及构造型式进行了论述,结合工程实例,对复合土钉墙在复杂地质条件下的使用状况进行了阐述。

Development and application of composite soil nailing walls in Shenzhen

The history of development and application of composite soil nailing walls in Shenzhen area were introduced.Four types of new composite soil nailing walls usually used in Shenzhen area were summarized.These composite walls included combination of soil nailing with cut-off wall(deep mixing piles or jet grouting piles) and prestressed anchors,combination of soil nailing with prestressed anchors,combination of soil nailing with micropiles and prestressed anchors,and combination of soil nailing with prestressed anchors,cut-off wall and micropiles.Design and calculation methods using a circular sliding method for checking the overall stability and the calculation method of pullout resistance of soil nailing were presented.The structural characteristics of soil nail,cut-off wall,prestressed anchor and micropile were also introduced.Finally,a successful application example using composite soil nailing wall was described.In the example,the composite soil nailing was used as a supporting system for deep foundation pit excavation at a site where difficultly geological conditions exist.