The Research Of Deep Foundation Engineering About The Optimization Design In Kunming Region

In recent years, with the rapid development of economy and city construction many high-rise buildings, subway and other projects like Bamboo shoots after a spring rain in our country city in recent years. at the same time, foundation pit engineering are more and more. So it has important significance that optimization design of deep foundation pit and study on the law of deformation. Because that Kunming area adjacent to the Dian Chi River Basin, the soft plastic to flow plastic peat soil distributes widely.,that resulted in many foundation face all sorts of difficulties in design, construction and excavation, theoretical research lags behind, that resulted many consequence. such as seriously waste, instability of foundation pit, cracking or even collapse accidents. Therefore, a safe, economic, reasonable supporting scheme is very important.From the actual situation, taking some deep foundation pit engineering in Kunming area for example, using FLAC3D to simulate on the foundation pit excavation step by step, calculated that the horizontal displacement, the ground surface settlement, the upheaval value, retaining pile internal force and axial force of cable of each condition is simulated And then the article compares and analysis simulation results,The calculation results of Li Zheng and monitoring data for comparative analysis, draws the following conclusion:First, the horizontal displacement:for the same condition in different position of the retaining pile of deep horizontal displacement, leading the calculation results is about1.05～1.87times of the measured results, the simulation results about the measured results of0.91～1.27times; for different conditions the maximum displacement of the roof, for computational results about test results1.24～1.58times, the results of simulation calculation is aboutl～1.22times of the measured results.Second, the ground surface settlement numerical simulation:settlement curve and Li Zheng software parabola method to calculate the settlement curve is more close to the measured curve, and compared with the numerical simulation results and measured results, more consistent.Third, the upheaval value:numerical simulation, measurement and calculation for three trends, variation is consistentFourth, he pile bending moment:for the results of calculation and measurement of difference, for calculation of the pile bending moment is about0.61-1.43times of the measured results, numerical simulation of pile bending moment is relatively identical with the actual conditions, numerical simulation of pile bending moment is about0.89～1.14times of the measured results.Fifth, anchor, axial force:numerical simulation results between canon law and elasticity method between calculation results, were less than the bolt design internal force. For the same excavation condition different row Cable axial force values for calculation of axial force of the anchor cable, about monitoring data of1.22～1.89times of the cable, numerical simulation of axial force of aboutl.11～1.32times of the monitoring date.In short numerical simulation on horizontal displacement, surface subsidence, heave, bending moment and axial force of pile anchor in five aspects compared with the results of measurement for anastomosis, and pathology results in the horizontal displacement and the anchor shaft power as compared with the measured result is too large.