倾斜旋喷桩帷幕复合土钉墙支护结构的工程应用  

Application of Combination of Soil Nailing Wall and Inclined Jet Grouting Cut-Off Wall as Deep Excavation Supporting Structure

作　　者：张军舰 李英杰 谭升 ZHANG Junjian;LI Yingjie;TAN Sheng(Geotechnical Technology Co.Ltd.,Hangzhou 31140l;Qingdao Yutai Foundation Engineering Co.Ltd.,Qingdao 266071)

机构地区：[1]岩土科技股份有限公司,杭州311401 [2]青岛玉泰地基基础工程有限公司,山东青岛266071

出　　处：《土工基础》2023年第6期882-886,共5页Soil Engineering and Foundation

摘　　要：首次将倾斜旋喷桩帷幕复合土钉墙支护结构应用于饱和砂层深基坑工程,并对支护结构坡顶位移和预应力锚杆轴力进行监测。监测数据表明,倾斜帷幕复合土钉墙支护结构顶最大水平位移和竖向沉降仅0.84H‰(H为基坑深度),远小于现行规范和标准,并与桩锚支护结构的0.57H‰和0.51H‰基本相当。在饱和砂层深基坑支护中倾斜帷幕复合土钉墙支护结构可替代桩锚支护结构。倾斜帷幕复合土钉墙支护结构造价为垂直帷幕复合土钉墙支护结构和桩锚支护结构的90%和73%,表现出了良好的经济性,锚固旋喷钻机解决了早期施工机械局限的瓶颈难题,该支护结构具有较大推广应用空间。The inclined high-pressure jet grout cut-off wall with the soil nails as the excavation support structure was applied to the deep excavation in saturated sandy soils.The deformation at the top of the supporting structure and the selected prestressed soil nails are instrumented and monitored.The deep excavation monitoring data pit show that the maximum horizontal displacement and vertical settlement of the top of the inclined high-pressure jet grout cut-off wall with soil nails are only 0.84H‰(H is the excavation depth),which is much smaller than the current code and specifications allowable values,and basically equivalent to the 0.57H‰and 0.51H‰of the soldier pile wall with the ground anchor supported structure.In the deep foundation in the saturated sand layers,the inclined cut-off wall with soil nail supporting structure can replace the soldier pile wall with ground anchored supported structure.The cost of the inclined cut-off wall with soil nail supporting structure is only 90%and 73%of the vertical cut-off wall with soil nail wall supporting structure and the soldier pile wall with ground anchored supporting structure,which demonstrates a very good cost-effective way for the excavation supporting structure.The specially designed inclined jet grouting drilling machine solves the bottleneck problem of the limitations of the previous construction equipment,and therefore provides a large growth space for the wider applications.

关 键 词：倾斜旋喷桩止水帷幕 复合土钉墙 深基坑支护 旋喷桩 预应力锚杆 

分 类 号：TU472[建筑科学—结构工程]