钻孔咬合桩在深基坑围护工程中的应用

钻孔咬合桩作为地下工程的新型围护结构,在我国建筑领域已逐渐被采用,并发展、成熟。咬合桩适用于不同地质条件下的施工,具有地层扰动小、抗渗能力强、造价低、施工速度快等优点。针对钻孔咬合桩的成桩工艺,施工过程中首先需要摸清地质水文情况;重点控制孔口定位精度、成孔垂直度、确保咬合厚度满足设计要求;严格控制超缓凝混凝土缓凝剂的掺量、缓凝时间、坍落度。利用咬合桩机成功处理地下障碍物,可解决SMW工法桩机、灌注桩钻机及顶管机遇地下障碍物无法通过的难题,取得较好的经济效益和社会效益。

Application of Cast-in-place Clutching Pile in Deep-pit Enclosure Works

The cast-in-place keying pile taken as the new exterior-protected structure of the underground engineering has been gradually used in the building field of China and developed well.The keying pile is suitable for the constructions under the different geological conditions,and has the advantages of small turbulence for stratum,strong impervious capacity,low construction cost and quick construction speed.In the light of the pile forming technology of the cast-in-place keying pile,it is firstly to find out about the geological hydrological conditions in the course of construction.The focal points are to control the precision of hole positioning and the verticalness of hole forming,and ensure the keying thickness meets the design requirements,and strictly control the retarder mixture,slow-curing time and slump of the super-slow-curing concrete.The utilization of the keying pile machine successfully deals with the underground obstacles,can solve the difficulties that SMW-processing pile machine,cast-in-place pile machine and pipe-jacking machine can not operate when meeting the underground obstacles.The economical benefit and the social benefit are achieved better.