The Bearing Capacity Mechanism Study For Post-grouting Of Cast In Place Pile

Compared to the bored pile,post grouting bored pile can improve mechanical properties of surrounding soil of the pile,curing bottom sediment,improve the properties of bottom soil of the pile,improve the bearing capacity of pile side friction and end,and greatly reduce the settlement of pile top,and greatly to improve the bearing ability of the post grouting bored pile,compared to other support with good economic and technical index.But,there are few researches on the supporting mechanism of post grouting bored pile,for example in practical engineering,post grouting bored piles have been applied more and more widely.Therefore,it is necessary to study the bearing behavior of post grouting bored pile.In this paper,it is analyzed that the mechanism of improving the bearing capacity of the pile after grouting and the main factors affecting the bearing capacity of the post grouting bored pile.This paper,on the basis of bored pile mechanism,used cylindrical cavity hole theory to calculate the initial pore pressure,and combined with the radial consolidation theory study on post grouting pile construction caused by the dissipation of excess pore pressure.Based on the principle of effective stress,obtained calculation method of effective stress of post grouting bored pile.Finally,combined with the pile-soil contact surface damage form,this paper obtain an analytical solution of the ultimate bearing capacity of single pile,and compared with the result of engineering project.Combined with the soil characteristics of Shandong Dongying Shengli oilfield engineering example,it simulated the effects bearing capacity factors of grouting bored pile after by using finite element numerical simulation software FLAC3 D to establish three-dimensional solid.By changing the pile length,pile diameter,consolidation grouting parameters,The bearing behavior and the settlement deformation characteristics of non grouting pile and pile-end grouting pile are analyzed by finite element simulation and comparison.The analysis results show that the post grouting technology of bored pile can significantly improve the bearing capacity of single pile and reduce the settlement of single pile under certain length of pile,grouting volume and solid diameter of pile end.