Continuum mechanical solution for negative frictional resistance of single floating pile under ground overload
A vertical displacement model based on pile-soil interaction and continuum mechanics was proposed to simulate the displacement of the pile-soil system in response to the negative friction force of a single pile caused by ground overload.The model included the displacement function of the pile-soil axis and the attenuation function along the radial direction.The total potential energy of the pile-soil system was obtained by using the variational calculus,and the coupled control equations for the pile-soil displacement and attenuation function in the displacement model were obtained.The iterative method was used to solve these two coupling functions,and mathematical expressions for key parameters such as pile axial force,neutral plane,negative frictional resistance,down-drag force,and equivalent stiffness of soil spring were obtained.The correctness of the proposed method were verified through comparison with in-situ experiments and existing theoretical results.The results show that the ratio of pile-soil modulus has a significant impact on the negative friction resistance and down-drag force of piles,and the position of the neutral plane is closely related to the slenderness ratio,while it is not closely related to the ratio of pile-soil modulus.As the pile-soil modulus ratio increases and the pile slenderness ratio decreases,the axial force at the same position of the pile increases significantly,but the growth rate slows down.The maximum settlement of soil displacement around piles under ground overload occurs at the surface,and the range of 0.3 times the pile length below the surface is a strongly affected area of displacement.The increase in pile slenderness ratio and pile-soil modulus ratio will both increase the range of influence on the displacement field of the soil around the pile.
ground overloadfloating pilevariational calculusneutral planedown-drag force
万方数据
维普
