Based On FLAC3D Software Three-dimensional Numerical Simulation Analysis On Pit Supporting

With the rapid development of our social economy, city buildings have been extended tohigher floor, which leads to sufficiently exploring and making use of underground space. Asthe basement has changed from a layer to multi-layer, the depth of foundation pits alsoincreases to dozen meters below surface correspondingly. Consequently, a large amount ofexcavation engineering emerges in cities. Excavation engineering, as the basis of the wholeproject, directly affects the safety, progress and quality of the main works. Thus, somecorresponding measures are needed to be taken to reinforce the foundation pits, in order toensure the completion of the whole project smoothly.At present, calculation theory and method of the pre-stressed anchor cable in the processof foundation pit reinforcement still stays on the limit equilibrium method of Rigidity theory.Moreover, the understanding of the deformation mechanism of foundation pit slope isinsufficient, regarding the side wall as a rigid body but not deformation; meanwhile analysisand design relying on practical experience. Nowadays, the numerical simulation technology isdeveloping continually, which provides a new approach for analyzing and designing of thefoundation pit supporting engineering.Based on specific project examples, the C’-Dsection of foundation pit supportingengineering is simulated and analyzed by using two different tools, analysis software ofLizheng stability and FLAC3D software. Then the thesis organizes the actual measurementdata. Finally, it compares and analyzes the calculating results obtained from the above threemethods, and then analyzes the stability of the foundation pit slope more accurately, verifiesthe correctness and feasibility of the design scheme.The detailed content of this thesis is listed as follows:(1) It reviews domestic development status of the foundation pit engineering and also thefunction and principle of pre-stressed anchor cable in the foundation pit reinforcement.(2)It analyzes and summaries the calculation theory of earth pressure, presents applicableconditions of each calculation theory, which lays the theoretical foundation for the latersoftware calculation.(3) It briefly introduces the basic principle and application scope of FLAC3D, andespecially makes a detailed description of the cable unit simulation. (4) Using stability analysis software to calculate C’-D section in foundation pit, and thenthe thesis puts forward the design scheme, finally verifies the feasibility of this designaccording to relevant specification.(5) On the basis of the calculations of stability analysis software, the thesis adoptsFLAC3D software to make two different (supporting before and after) three-dimensionalnumerical simulation to the C’-D section of foundation pit, which can reflect the forces andposition changes of the interior of foundation pit intuitively and accurately. This embodies thekey role of the pre-stressed anchor rope supporting system in the foundation pitreinforcement.(6) Combined with field monitoring data, the thesis makes a comparison in calculationresults among of FLAC3D, Analysis software of Lizheng stability and field measured data, soas to verify the correctness and effectiveness of FLAC3D numerical simulation, whichprovides valuable reference for the future engineering design and construction.