Research On Post Grouting Technique Of Bored Pile And Its Application In Zhoushan Area

Bored piles as a common form of pile foundation is simple in construction,the formation,such as strong adaptability and economic cost advantages,particularly suitable for on the soft soil foundation construction of high-rise buildings and large span industrial buildings such as the upper load large buildings.But because of the bored piles and stress relaxation of mud by the side of pile,pile end sediment subsoil disturbance,pouring concrete quality of pile,and the same venue discreteness of vertical bearing capacity of the bored piles.Bored pile post grouting technique arises at the historic moment,it not only can reduce the settlement of pile foundation,but also improve pile bearing capacity.The research of this paper is started on the advantages of post grouting technique and engineering application,analysis of bored piles in detail on the basis of the function and mechanism of grouting technique,through the theoretical analysis,the pile static load test,engineering experience and the way of post grouting pile bearing capacity,settlement characteristics and its application in Zhoushan area were studied.At first,this paper analyzes the mechanism of the effect of post grouting bored piles and reinforcement,summarizes the commonly used after grouting pile ultimate bearing capacity and settlement calculation method.And then put forward the bored piles after grouting technique in the process of design and construction key points and matters needing attention,summarizes the design method of post grouting piles,the construction technological process and main points of the quality inspection.According to the hydrogeology characteristics of Zhoushan area,summarizes the Zhoushan area commonly used form of pile foundation,the advantages and disadvantages of all kinds of pile type and applicable area.Combined pile static load test results,the system is analyzed in the Zhoushan city new district within the CBD area of post grouting piles work performance and application situation,and compared with no grouting pile,and put forward based on the foundation in the specification in the formula of single pile bearing capacity characteristic value of Zhoushan city new district after grouting pile bearing capacity of composite increase coefficient,subsequent similar project in Zhoushan area has good reference value to the design and construction.