锤击贯入PHC开口管桩现场监测试验研究

现场试验研究为工程实践积累经验和数据,并促进相关理论研究的发展。以马鞍山发电厂2×660 MW改扩建工程#1汽机房预应力高强度混凝土管桩(PHC)施工现场监测试验为例,探讨了锤击贯入开口式PHC管桩在沉桩过程的挤土效应和土塞效应。在简要叙述现场监测试验内容和方案的基础上,通过对现场沉桩施工的深层土体位移、孔隙水压力、锤击贯入度、土塞高度的现场监测试验数据分析,初步评价了沉桩的挤土效应和土塞效应对施工的影响。最后基于监测成果分析,论证了施工方案的技术可行性。并基于工程实例得到了管桩的挤土效应,随着管桩入土深度的增加而逐渐减弱,中上部土层反应明显,而下部土层则影响甚微的结论,研究能对后续以及类似地层场地的施工提供了有效的作业指导。

Field Monitoring Test Research of PHC Open-end Pile with Hammer

Field tests are used to accumulate experience and data for engineering practice, and promote the development of the relevant theories. Take the construction site monitoring test of prestressed high strength concrete pipe pile(PHC) for example, which is in #1 turbine room of 2 ? 660 MW reconstruction projects in Ma on shan power plant, the paper discusses compaction effect and soil plugging effect in the process of PHC Open-end Pile with Hammer. Based on the brief narration of the field monitoring test contents and scheme, preliminary evaluation is on the compaction effect of pile and soil plugging effect to construction, through to the field monitoring test data analysis of the site of the construction of the pile soil mass displacement of deep layer, pore water pressure, hammering penetration degrees and soil plug height. Finally, based on monitoring results, it demonstrates the technical feasibility of the construction scheme, and based on the engineering example got a conclusion that the compaction effect is weakened gradually with the increase of the depth of pile soil, and the obvious response is on the upper soil, and the lower soil is little. The research provides effective work instruction on the follow-up and similar strata construction.