摘要
在诸如"大三石"和岩石等复杂地层中施工灌注桩,常采用冲孔法。有时也采用爆破法、回转钻进、潜孔锤钻进,或采用冲钻爆抓等复合方法,但工序复杂,成桩工效较低。将韩国生产的上下旋转动力头及高压潜孔锤与合金钻头和螺旋钻杆整合到国产液压步履或履带行走的桩机上,同时将护壁钢管设计成具有高切削能力的钻具,形成了双动钻具,提高了对复杂地层的钻凿能力。钻凿的岩屑通过螺旋钻杆从出土口排出,克服了常规潜孔锤法在潮湿地层钻进中排渣不畅的缺陷。护壁钢管的快速插接技术既减少其接长耗时,又降低沉拔管启动摩阻力。新技术实现了全桩长钢管护壁干取土,是一种无泥浆污染的环保施工技术。工程实践表明,新技术1天可完成5~7根复杂地层条件下的嵌岩桩,相比冲孔法,工效大增。
The common method used in construction of bored piles in complex formation, such as 'three-large-stone' formation and rock, is the punching method. Sometimes, blasting, rotary drilling, DHD(down-hole hammer drilling), or their composite method are also used in the same formation. However, the pile-forming efficiency is lower due to the complex pile-forming process. The upper and lower rotary power devices, high pressure DHD, alloy boring crown and spiral drill pipe, produced by Korea, are integrated with Chinese domestic hydraulic walking or crawler pile machine, and the casing pipe is designed as the drill tool. Then a double dynamic drilling tool with high drilling ability in the complex formation is formed. Drilling cutting is discharged from the unearthed port by spiral drill pipe, so the defect of poor slag dumping in wet ground for DHD is overcome. The technology of fast plugging pipe is used to shorten the connect time and reduce the starting friction between the pipes and the soils in pipe sinking and pulling. The new method is a kind of environmental protection construction method due to the soil slag dry-dumping technique. Engineering practice shows that 5~7 piles are made by using the new method in 1 day. Compared with that of the punching method, the pile-forming efficiency is greatly improved by the new method.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2013年第S2期1188-1191,共4页
Chinese Journal of Geotechnical Engineering
关键词
复杂地层
“大三石”
大孤石
双动钻进
全桩长护壁
灌注桩
嵌岩桩
complex formation
'three-large-stone'
large boulder
double dynamic drilling
hole wall protection in full length pile
cast-in-place pile
rock-socketed pile
