关键词: 插桩深度预测, CPT原位测试, 砂性地基, 桩靴端部型式, 接触应力分布, 有限元方法

Abstract: The distribution form of contact stress between the bottom of pile shoe and foundation has a significant effect on the penetration depth of pile, and the magnitude and distribution form of contact stress are associated with the tapered tip type of the pile shoe. Therefore, taking the pile penetration project in Qidong, Jiangsu province, as an example, the relationship between the tapered tip type of pile shoe and the penetration depth of pile has been discussed. Based on the field monitoring data of contact stress under different pile shoes, the penetration depth of pile has been calculated by empirical formulae recommended in the engineering specifications at home and abroad and numerical simulation method, respectively. The results demonstrate that the contact stress in the middle area is greater than that at the edge of the pile shoe with different cone end forms. The characteristic of stress distribution is similar to that of flexible plates. When the penetration depth of pile shoe is predicted according to the empirical formulae recommended in the engineering specifications, the effect of the shape of pile shoe on penetration depth can be ignored, and the calculated value is basically consistent with the field measured one. The penetration depth of pile predicted by small deformation finite element numerical method is satisfactory. The conclusions of this paper can provide reference for similar engineering practice.

Key words: prediction of spudcan penetration depth, CPT measurement, sandy soil foundation, toe shape of spudcan, distribution of foundation contact stress, finite element method