利用旋挖工艺优化嵌岩桩的勘测方案

现行的标准对端承桩的勘探点间距与持力层层面坡度的变化情况做出了严格的规定,但在以基岩作为桩端持力层的场地,由于受沉积环境与地质构造的影响,持力岩层的层面变化较大,如果严格按打入桩的要求来控制,则勘察工作量将大幅增加,而且也很难做到。旋挖桩的成孔过程客观上起到了钻探的作用,在施工过程中可以很好进行桩端持力岩层风化程度的鉴别,有效地控制进入持力层的深度,确保桩侧与桩端阻力的发挥。本文结合工程实例,探讨了在基岩地区采用旋挖桩时,可以对勘探点间距与持力层层面坡度变化的规定作适当的放宽处理,旨在为旋挖桩的勘测方案优化积累一些有益的经验。

Optimizing Survey Scheme of Embedding-Rock Pile Making Use of the Swivel-driven Technology

The active criterion strictly stipulates spacing of exploration point and lay gradient of bearing stratum for end-bearing pile,but in the site where the rock is for bearing stratum,the lay gradient of rock undulates in large extent due to sedimentary circumstance and geologic structure.The workload of reconnaissance will increase in large amount and the work is very difficult to be finished according to the desire for driven-pile.The swiveldriven pile objectively take the role of exploration in the course of driving,it is benefitial to distinguish the degree of weathered rock for bearing stratum and control the depth into bearing stratum for exerting the shaft and tip resistance.The paper discussed the swivel-driven pile in the rocky site and suggested that the stipulation for spacing of exploration point and lay gradient of bearing stratum could be extended,it aims to pile up some useful experience for optimizing survey scheme of embedding-rock pile.