扩底抗拔桩试验分析与抗拔承载力计算方法

Experimental Analysis and Calculation of the Up-lift Resistance Bearing Capacity of Bored Cast-in-place Pile with Enlarged Bottom

为了了解扩底抗拔桩的抗拔机理和抗浮特点,进行扩底抗拔桩和等截面抗拔桩的试桩试验。试验表明,扩底抗拔桩可以大幅度提高桩的抗拔能力。通过试验,分析了扩底抗拔桩抗浮作用机理,得到了扩底抗拔桩的上拔规律。根据作用机理,结合已有公式,探索出扩底抗拔桩单桩极限抗拔承载力设计的计算方法,从而进一步为扩底抗拔桩在软土地区中的应用提供借鉴。

In order to understand float resisting mechanism and its characteristic a test on the bored cast- in-place pile with enlarged bottom and up-lift resistance pile with equal section is carried out. It is found that the bored cast-in-place pile with enlarged bottom can improve the float resisting capability to a great extent. Through the test, the suffering force mechanism and up-lift disciplinarian are discussed. Based on the float re- sisting mechanism and the existed formula, the calculation for up-lift resistance bearing capacity of bored cast- in-place pile with enlarged bottom in the deep foundation of soft clay area is obtained. It extends the use of the bored cast-in-place pile with enlarged bottom in the deep foundation of soft clay area.