| Many experts and scholars have done a lot of related research on horizontal bearing capacity.However,the research on penetration problems and horizontal bearing characteristics of concrete solid square piles is relatively few.This paper mainly discusses the problems of continuous static pressure penetration and horizontal bearing characteristics of solid square piles through theoretical research and numerical analysis simulation of finite element software,and lays a foundation for practical application and further study.The main contents of this paper are as follows:1.On the basis of previous solid square pile test in situ,the finite element software ABAQUS is used to establish the numerical analysis model.The correctness of the model is verified by the comparison of the pile top displacement,and the horizontal displacement of the pile,the damage area and the pile body cracking after numerical analysis,and the results are compared with the in-situ test data.It can be further studied based on this model.2.A numerical model of local engineering is established to carry out a systematic study of horizontal bearing capacity.The main conclusions are as follows:(1)When the same lateral load is applied,the elastic modulus has little influence on the horizontal bearing characteristics of the solid pile,and the larger the internal friction angle can effectively enhance the horizontal bearing characteristics of the solid pile.Increasing the cohesive force of soil can also enhance the horizontal bearing characteristics of pile foundation to a certain extent,and reduce the horizontal displacement of pile top,but it has no effect on the moment value of pile body.(2)The increase of vertical load can greatly increase the peak bending moment of solid square pile,and at the same time,it will also improve the horizontal bearing capacity of solid square pile.The effect of the vertical load on the sandy soil is obviously different from the vertical load in the clay.The vertical load in sandy soil shows a linear change,while the vertical load in the clay appears to be nonlinear.In this paper,the optimum value of vertical load of square pile in sandy soil is 0.4Vult,and the optimal value of vertical load of clay is 0.6 Vult.(3)The lateral movement of the top of the pile can be significantly reduced when the fit ratio changes from low to high.The acceptable value of the lateral bearing capacity of the pile with low filling ratio is controlled by the fracture of the pile body,and when the filling ratio is high,the acceptable value is controlled by the horizontal displacement of the pile head.The effect of increasing the pile strength ratio of square pile on the allowable value of transverse bearing capacity is very small,but for the case of high filling rate,the allowable value of transverse bearing capacity is more important.3.(1)Based on the numerical model of ABAQUS,the effects of static pressure penetration on soil,soil parameters on penetration resistance and penetration velocity on penetration resistance are analyzed.The main conclusions are as follows:(1)With the increase of penetration depth,both radial and vertical stresses show the phenomenon of maximum stress first,then decrease.Because of the degradation effect of lateral resistance,the effect on vertical stress is greater.The radial displacement mutation occurred at the junction of laminar soil.(2)The reduction of static lateral pressure coefficient K0 can reduce the penetration resistance,and the squeezing effect of solid square pile is obvious.The increase of friction coefficient ? makes the penetration resistance greatly larger and the mutation occurs at the junction of the laminar soil.(3)When the penetration depth is the same,the greater the penetration velocity v,the greater the penetration resistance.Considering penetration resistance and construction efficiency in a comprehensive manner,it is recommended that the penetration speed be 0.1m/s?0.2m/s as the best static construction penetration rate. |
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