The Design And Conduction Of Pile Foundation For Urban Flood Control Projects Of Guang Xi

For some limitations, many engineers always use the conventional design method of piles in the work of piles design. The method believes.the entire loads, are subjected to the pile so as to bring large waste. Although combined action, which means the whole structural load is assigned to piles and caps or rafts in proportions with the elastic theory, between pile and soil is considered, it is different from the settlement control method of composite piles. As a new type method for pile design, the settlement control design method for composite piles foundation has a board and bright future.The paper shows the advantage and disadvantage of optimization method for general piles foundation and composite piles controlled by settlement from the optimum design for piles foundation. The computation comparison is conducted in this study for the design of pile foundation for urban flood control projects by the three methods of pile embedded in rock and of non-pile embedded in rock and of composite piles control led by settlement from the optimum design. It is proposed that in the area where the hard plastic soil layer is thick enough, it is not necessary to locate the bearing stratum of the pile foundation on fresh rocks given condition that the loads of urban flood control project are not substantial. In stead, the bearing stratum can be located on stiff-plastic soil layers. Different choices of bearing stratum would result in differentproject cost and construction time.The result shows that composite piles foundation controlled by settlement can obtain better benefits and assure better security for projects.