【摘要】 目的研究成桩工艺对黏性土中单桩承载性状及承载力的影响机理,为工艺设计提供参考.方法根据相似理论和模型试验方法,建立桩-土之间的相似系统,结合常州高架道路一期工程中特定黏土层性质,配置相应人工土,在人工土中分别设置混凝土预埋桩、静压桩和钻孔灌注桩并测试桩身力学数据.结果通过对模型桩进行静载试验,获得黏土中不同成桩工艺单桩荷载传递规律和承载性状.设计荷载时,静压桩、灌注桩和预埋桩桩端荷载占桩顶荷载的比例分别为5.9%、4.7%和3.2%.结论由成桩工艺造成的桩-土作用的不同对桩基承载性状及承载力具有很大影响,桩周土体侧向卸载不仅影响侧阻力的发挥,同样会削弱桩端阻力的发挥.更多还原

【Abstract】 In order to analyze the influence mechanism of set-up process for the load-bearing capability of single pile,similarity theory and model experimental method are applied to build the pile-soil similarity system which can be used to design the indoor model experiment.The artificial soil is configured to formulate the clay soil of specific layer in Changzhou Viaduct Project.Three types of piles are set up:built-in pile,jacked pile and cast-in-place pile,and all piles are made of concrete.Afterwards,the static load test is carried out and mechanical data are got,and the load transfer law and bearing capability of testing piles are analyzed.It proves that the pile set-up process has a great influence on the bearing character and bearing capacity of single pile.Under design load,the proportions of point resistance in total resistance of jacked pile,cast-in-place pile and built-in pile are 5.9%,4.7% and 3.2%,respectively.And lateral unloading of soil can weaken not only the frictional resistance but also the tip resistance.更多还原