铁矿夹层地质长螺旋钻孔压灌桩施工技术

Long Spiral Drilling Pressure Filling Pile Construction Technique Under the Geological Condition of the Iron Ore

某工程桩基础选用长螺旋钻孔压灌桩,局部场地内存在一层坚硬的铁矿夹层,导致长螺旋钻机钻成孔困难,甚至出现无法钻进的情况,长螺旋钻孔压灌桩无法正常施工。通过方案对比,采用旋挖机提前干作业引孔,穿透坚硬夹层,回填孔位后再用长螺旋钻机进行作业的施工技术,有效解决了场地内分布有铁矿夹层等坚硬岩层对长螺旋钻机成孔有影响的难题。通过工程实践,采用旋挖机引孔技术不仅可以确保施工进度和质量,而且环境污染小,可降低工程造价。

A pile foundation selection of long spiral drilling pressure filling pile,local memory space in a hard layer of iron sandwich,resulting in long auger drilled holes difficult,Even circumstances beyond drilling,long spiral drilling pressure filling pile can not normally construction. After a comparison of several alternatives,a pilot hole using a rotary digging machine was created,which worked in dry condition and drilled through the hard inclusion layer,filling holes before the construction technology operations with a long auger. This approach was found effective in solving the trouble with drilling using a long screw auger in horizons with iron ore or other hard material inclusions. The results of the practical works suggest that using a helical digger to drill a pilot hole not only guarantees construction progress and quality,but generates less environmental pollution and reduces construction cost as well.