Analysis of Comparison of Calculation Methods for Downdrag of Single Pile

Abstract

The problem of negative skin friction has acquired great importance for the circles of civil engineering over that last few decades. It aims to understand the mechanisms of pile-soil interaction, define more adequate analytic methods for the load transferand and ensure the bearing capacity of pile foundation. But for the complexity of problems, there are some issues that have not been well solved in engineering practice.In order to avoid the failure of pile body, the uneven settlement of pile foundation and other engineering disasters, the researches of downdrag have been carried out since 1965. And engineers have proposed a number of calculation formulas for the downdrag of single pile, yet the calculation results differ sharply on account of the respective applicability and limitation of these formulas.This paper introduces several common calculation methods of downdrag on single pile and recommends diverse calculation situations in self-weight collapsible loess area. In this paper, some calculation methods based on limit analysis method will be compared from different angles and the applicable conditions, advantages and disadvantages, etc. are also discussed to provide reference for practical engineering design.