滨海软弱土条件下的PHC管桩挤土效应试验研究

Experimental Research on Soil Squeezing Effect of PHC Pipe Pile Under Condition of Coastal Soft Soil

结合工程实际并通过现场监测,测试在滨海软弱土区域进行PHC管桩压打过程中的四周土体位移和孔隙水压力。监测结果表明:离压桩位置越近的地基土的侧向位移越大,在影响范围内的孔隙水压力一直升高,压桩结束后,孔隙水压力消散比较缓慢;压桩挤土效应影响范围可取为桩长的0.85倍。通过监测可以确定软弱土孔隙水压力分布规律和桩的偏位规律的影响范围,其结果可以指导大面积进行PHC管桩施工时控制桩机的压桩路线、顺序以及桩机间的施工半径。

Combined with engineering practice,through on-site monitoring,the surrounding soil displacement and pore water pressure during pressing of PHC pipe piles in coastal soft soil area are tested.The monitoring results show that the closer the soil is to the pile pressing position,the larger the lateral displacement of the foundation soil will be,and the pore water pressure in the affected area will increase all the time,after the pile pressing,the pore water pressure dissipates slowly;the influence range of soil squeezing effect induced by the pile pressing can be 0.85 times of the pile length.Through monitoring,the distribution law of pore water pressure in soft soil and the pile deviation law can be determined.The results can guide the piling route,sequence and construction radius of pile driver during the construction of large area PHC pipe piles.