Method for analyzing longitudinal vibration of tubular pile on basis of radial heterogeneous viscous damping soil model

Abstract

The invention discloses a method for analyzing longitudinal vibration of tubular pile on the basis of a radial heterogeneous viscous damping soil model. According to the method, outer soil and inner soil are assumed to be a series of thin layers which are independent from each other, and mutual effects among the soil layers are ignored; a soil body around the pile is portioned into an interior area and an exterior area, the interior area is partitioned into an arbitrary number of circular layers, a soil body unit in each circular layer is a homogeneous and isotropic linear elastic body, a soil body in the exterior extend infinitely along a radial direction, viscous damping is adopted for soil body material damping, and radial displacements of the soil bodies are ignored; on two sides of a pile soil face and every circular layer soil face are continuous in displacements and balanced in stress, and vibration of a pile soil system appears as small deformation; concrete in a pile body is linearly elastic, and stress wave propagation in the pile body meets a plane cross-section assumption; according to basic theories of elastokinetics, longitudinal vibration equations for the soil body around the pile, an inner soil body and the pile body are established; by Laplace conversion, the three equations in the step 5 are solved to obtain a time-domain speed response function of any excitation force at the pile top.

Description

technical field [0001] The invention relates to the field of civil engineering, in particular to a method for analyzing the longitudinal vibration of pipe piles based on a radial heterogeneous viscous damping soil model. Background technique [0002] The study of pile-soil coupled vibration characteristics is the theoretical basis of engineering technology fields such as seismic design of pile foundations and dynamic testing of pile foundations, and has always been a hot issue in geotechnical engineering and solid mechanics. [0003] As we all know, in the process of pile foundation construction, due to the influence of soil compaction, relaxation and other disturbing factors, there is a certain inhomogeneity in the soil around the pile along the radial direction of the pile foundation, that is, the radial heterogeneity effect. In order to consider this radial heterogeneity effect, many scholars at home and abroad have made a lot of achievements. These results can be classi...

AI Technical Summary

Problems solved by technology

However, for the problem of anharmonic vibration (transient vibration or random vibration), the hysteretic damping model is not suitable, especially when studying the time domain response of piles under transient excitation conditions, the soil damping force is also related to the amplitude Related to the strain rate, the use of the hysteretic damping model will cause contradictions in the concept, resulting in the so-called "non-causality of dynamic response", while the viscous damping model is more suitable and more reasonable in physics

[0008] In addition, most of the current research is carried out on solid piles, and for large-diameter tubular piles, due to the existence of pile core soil, there must be differences in the vibration characteristics between them and solid piles.

Images