螺纹结构对螺纹桩双桩竖向承载特性的影响研究OA

Based on three-dimensional finite element numerical simulation analysis,a numerical analysis model of double piles under vertical load was established,and the influence of different design parameters(including pile spacing,thread height,and thread length)on the vertical bearing characteristics of double piles of threaded piles was investigated.Meanwhile,the change rule of the soil displacement nephogram around the pile was analyzed,and the axial force transfer characteristics of the pile shaft were revealed and combined with the effect of bearing capacity and pile utilization rate of pile body material in order to explore the optimal design interval of the threaded structure.The results show that:with the increase of pile spacing,the mutual interference effect between piles is reduced,the load-bearing capacity of double piles is increased,and the load-bearing performance of double piles is better when the pile spacing is 4~5 times the pile outer diameter.Increasing thread height can strengthen the mechanical occlusion of the threads with the soil,which in turn enhances the bearing capacity of the double piles.In addition,the double-pile bearing capacity with the ratio of the thread height to the inner diameter of the pile of 0.5~0.6 is fully utilized.Increasing the thread length can effectively increase the contact area of the pile-soil body,thereby enhancing the lateral frictional resistance of the pile and improving the double-pile bearing capacity and the utilization rate of pile material.The optimal double-pile bearing performance was also obtained with a thread length to pile length ratio of 0.6~0.7.The most efficacious method of enhancing the bearing capacity of double piles is to increase the thread length.