Improved method for calculating settlement of pile foundations and case studies

Based on the test results of 153 field test piles, various complicated and different shaft resistance distributions under working loads (characteristic values of bearing capacity of piles) are generalized into four types: regular trapezoid, cone head, garlic head and concave valley, and the additional stress coefficient within the projection range of pile section is homogenized. At the same time, the additional stress coefficient of the affected piles in the range of section projection is homogenized. Based on this, the concrete steps and detailed rules for calculating the settlement of conventional and composite pile foundations by the method of layered summation for the homogenized additional stress of pile foundations are put forward. Through 6 groups of model tests and 8 practical engineering cases, it is shown that the settlement value of pile foundations calculated by the proposed method is close to the measured one without correction.