In order to explore the rebound properties and the residual stress characteristics of jacked piles,so as to make full use of its bearing capacity,the rebound characteristics of jacked piles under different pile sinking rates and unloading rates are analyzed,through the jacked pile sinking and static load test,combined with the finite element simulation method,with the influence of pile end residual stress on the ultimate bearing capacity of jacked piles summarized.The results show that the rebound a-mount of the pile body accounts for 80％of the total rebound amount of the pile body during the un-loading process,and the rebound displacement of the pile body gradually stabilizes after unloading.Af-ter the pile sinking,the maximum stress of the soil around the pile reaches 4.5 times of the passive earth pressure.After unloading,the lateral pressure stress dissipation of the shallow soil around the pile is greater than that of the deep soil.The more the stress consumption of the soil at the pile end,the smaller the residual stress at the pile end,and the more the rebound of the soil at the pile end after un-loading.The increase of pile sinking rate and unloading rate would lead to the decrease of residual stress at the pile end,and reduce the bearing capacity provided by the soil at the pile end,resulting in the decrease of bearing capacity of the pile.It is concluded that the residual stress of the jacked pile is the main factor affecting the bearing capacity,and the unloading rate has the most obvious influence on the residual stress of the jacked pile.
关键词
静压桩/残余应力/回弹变形/极限承载力/有限元模拟
Key words
jacked pile/residual stress/rebound deformation/ultimate bearing capacity/finite element simulation
维普
万方数据