预应力机械式钉锚在超大无内撑深基坑中的应用

Application of Prestressed Mechanical Type Nail Anchors to Super Large No-Inner-Support Deep Foundation Pit

普通摩擦型锚杆的抗变形控制能力较差,尤其当基坑影响范围内存在既有建(构)筑物、地下管线或道路时,往往不能满足抗位移要求。结合工程实际,介绍一种创新型的基坑加固支护技术——预应力机械式钉锚。该工艺采用预应力和扩大头锚杆来增加端面阻力,能有效控制基坑位移,大大提高了基坑的安全性,同时亦具有良好的经济效益。

Traditional friction-type anchor has poor control ability of resistance to deformation, especially when there are existing buildings （structures） and underground piles or roads surrounding the foundation pit, and in most cases, it cannot meet the requirement of resistance to displacement. Based on engineering practice, this paper introduces an innovative reinforcement support technology for foundation pit, known as -- prestressed mechanical nail anchor. By using prestressed and expanded anchor to increase the end resistance, such technology can effectively control the displacement of the foundation pit, highly improve the safety of the foundation pit, and has good economic benefit.