| CFG pile composite ground technology was applied in multistoried building at first, and developed to be applied in high-rise and super high-rise building widely through more than twenty years of scientific research and engineering practice. It is obtained remarkable economic and social benefit. This paper mainly finished the following:1. Adopted the large-scale indoor test to simulate the eccentric loading effect of connecting body of high-low rise building. Based on the results of the test, it is obtained that base reaction of natural foundation and uniform layout of CFG piles composite ground under axis loading can be simplified as uniform distribution, the base reaction of natural foundation and uniform layout of CFG piles composite ground under eccentric loading can be simplified as linear distribution, and the non-uniform layout of CFG piles composite ground under eccentric loading is non-linear distribution. The non-uniform layout of CFG piles composite ground under condition of equal deformation is non-linear distribution, which the end of long pile is higher and the end of short pile is lower, both can be simplified as uniform distribution, and it is distributed by the composite modulus of high-rise part and low-rise part.2. Based on static equilibrium equation expressed by concentrated force, the bearing capacity formula of multi-type-pile composite foundation was derived. It is pointed that the bearing capacity improvement factor of soil between piles is tight link with soil features, construction technology, and pile spacing. It is put forward that how to part the area, how to calculate the improvement factor of composite modulus, how to lay the soil along the depth and how to calculate the composite modulus of each layer when calculating the deformation of multi-type-pile composite foundation. The procedures of calculating the deformation of composite ground is also given.3. According to problem of selecting the incorrect compression modulus to calculate the deformation of natural foundation and CFG piles composite ground in currently, simulating the consolidation test results is put forward. Based on comprehensive analysis a lot of simulating mathematical models put by the previous, a new mathematical model is put forward as followding: eï¼c[exp(-aNpbx)-1]+e0The above formula has the characters of satisfy the boundary conditions, monotone decreasing and showed the shape of "S". Each parameters of the formula have the unique value by the optimization method. A visual program is compiled by VC++computer language. It is indicated that the mathematical model put forward by this paper has high fitting degree, and better than models put forward by the previous according simulating a lots of compression modulus test results. It can apply the model put forward by this paper to simulate the compression modulus test results directly, in order to calculate the compression modulus of pressure section between gravity stress and the sum of gravity stress and additional stress. It is achieved the man-machine interaction, avoided human error, and improved the calculation accuracy of deformation. |
