Study On The Bearing Characteristic Of Cement Mixing Pile Composite Foundation And Applying In The Soft Soil Subgrade

With the popularization and application of the cement mixing piles in groundprocessing, disturbance is relatively small, construction is simple and rapid, low costand effective, as a way of soft soil foundation improvement, cement mixing pilecomposite foundation has gotten great concern of the domestic and internationalgeotechnical community, people began to pay attention to the study of cement mixingpile composite foundation. Cement mixing pile has a unique performance ontechnology and economy, and the application is quite extensive, but it’s design andcalculate theory is not very mature, construction methods and quality inspection arestill exist many problems to be solved. There have been many engineering accident inengineering practice. It is necessary to conduct further research in aspects of bearingmechanism and the calculations of bearing capacity and settlement.Bearing mechanism, bearing capacity calculating and settlement calculating ofcement mixing pile composite foundation are all important. Through two ways oftheoretical derivation, measured data, cement mixing pile composite foundation hasbeen made relatively careful research in this article. Firstly, the bearing mechanism ofcement mixing pile composite foundation has been analyzed, composite foundationunder rigid foundation has been compared with composite foundation under flexiblefoundation, rigid pile composite foundation has been compared with flexible pilecomposite foundation. On this basis, the influencing factors of load transfer of cementmixing pile composite foundation which under the load of embankment has beenanalyzed. Secondly, through theoretical analysis of the typical unit in the compositefoundation, deduced the expression of the ultimate bearing capacity of compositefoundation. Then, the method of settlement calculation has been argued. According tothe characteristics of the side friction of pile, assumed the distribution form of theside friction of pile, introduced the unit model and the displacement pattern of the unitmodel, a new kind of method to calculate compression of piles and soil between pilesin cement mixing pile composite foundation is presented. On this basis, thecharacteristics of deformation of cement mixing pile composite foundation has beenresearched through analysis of example, then argued the influence to the traits ofcement mixing pile composite foundation of various factors, such as cushionthickness, load level, the compression modulus of soil between piles, the replacement rate and so on. Lastly, applied the method in this paper to the practical engineeringproject to forecast the settlement of cement mixing pile composite foundation.