Post Pressure Grouting Of Rotary Digging Bored Pile Quality Control And Testing

The quality of pile foundation and cost control have been the focus of the construction industry,rotary bored pile also has a common problem of pile foundation.Although strictly control the construction quality of each stage,due to the influence of the construction process and other unfavorable factors,the quality of pile body is not easy to control,the bearing capacity of the pile body is insufficient or the integrity of the defects often occur.So it is inconvenience to the subsequent construction and it has left hidden danger to the overall structure of the buildings stability.In order to ensure the bearing capacity of pile foundation and limit the settlement of pile position,the present method is mainly to increase the diameter of pile,the end of pile and the technical post grouting.In this paper,combined with a building pile foundation engineering in Handan,Hebei,the main research problems are:1.Understand the domestic and international research status of grouting technology,analysis the impact of the various factors of the quality and bearing capacity of rotary bored pile.The problems encountered in the construction and the solving methods about the mechanism of the post grouting technology to reinforce the soil body,the mechanism of improving the bearing capacity.2.Comparison of calculation method of bearing capacity and calculation method of bearing capacity of bored pile.Compared with the grouting parameters and the increase of bearing capacity about pile end bearing stratum is different soil mass and the best grouting ratio of different soil mass is understood.3.With the help of geotechnical finite element analysis software MIDAS/GTS NX to establish three-dimensional model of pile soil,simulate rotary digging pile static load test of single pile,compare the same load before grouting and after grouting pile top settlement value.Study on loading pile-soil relative displacement change,the pile soil stress changes,and the post grouting pile without grouting pile bearing capacity curves and contours,and the feasibility of increasing the diameter of the pile,the end of the pile and the post grouting is analyzed and compared.