Study Of The Characteristics Of CFG-pile Composite Subgrade Under Tall Building Box Foundations

Theory analysis of composite subgrade has got behind practice engineering of it in recent years. In correlation code, design and construction of composite subgrade have actual being unsureness for complex of geotechnical conditions. As a technician of geotechnical engineering, what he need is accuracy of design as well as reliability, safety and economy of build engineering. Method of FEM has been found application in practice engineering for which can erect model of calculation by specially boundary conditions and obtain exact explain.Through established a three-dimension model, this paper makes use of ANSYS FEM software analysis and study of the characteristics of CFG-pile composite subgrade under tall building box foundations (parameter of model was acquired from CFG pile composite subgrade of Beijing Jiachen plaza). Result of analysis detailed explain its characteristics from six-aspect.1. Bring diverse pressure to bear on motherboard of foundation.2. Distinct thickness of motherboard of foundation.3. Difference replacement rate of area of CFG-pile under the motherboard of foundation.4. Disparate thickness of cushion of CFG-pile composite subgrade.5. Different longth of CFG-pile.6. Distinct outward extension of CFG-pile in the core region.After analyze stress field and deformation field of CFG-pile composite subgrade , a good result were had application in composite subgrade of Beijing Jiachen plaza (twenty-six floor on ground and three floor under ground). At the stage of construction, a practice text was taked about nature foundation, CFG-pile and composite subgrade bearing load and pile-soil ratio of stress. At the same time, a long period of observation were put in practice when gradually add load of construction. In the end, good conclusions with satisfied economic was been given through comparing of results of tests in site, FEM simulation and calculation of...