The Changsha City Geological Home Ⅱ Deep Excavation Engineering Monitoring And Prediction

With the continuous development of economic construction,our variousconstruction get improved, there has been a lot of deep excavation in the process, thescale enlarges a lot as well as the depth deepends,which requires bigger challenge ofengineers Deep foundation pit is a complex engineering and influenced by variousfactors,which is crossed with monitoring technology, geotechnical engineering,structural engineering, construction technology, environmental engineering and otherdisciplines, its deformation influence by a variety of complex factors. To meet safetyand quality standards, the deformation of deep foundation must be controlled within acertain range. Given the complexity of the actual project,excavation is needed tomonitor through the dynamic monitoring deformation data to reflect the pit, andprovide a basis for predicting post-deformation pit.In this paper, based on pratical works-Changsha Geological home Ⅱ deepfoundation pit,the author makes the prediciton of deformation:1Through the review of literature,the author understands the characteristics ofdeep excavation and commonly used forms of support,and analyzes the deformationmechanism and characteristics of deep excavation. In the case of Geological home Ⅱdeep excavation, development of monitoring programs, measurement point, andalarm monitoring methods are planned. Sedimentation analysis of surroundingbuildings was monitored, the settlement value of the column and the top horizontaldisplacement value changes of the supporting structure, and with the alarm valuecompared to determine the security status of the deep pit. By construction schedule,rain caused flooding expansive soil, the impact of measurement error and otherfactors, there is fluctuations in monitored value.2Using FLAC3D software to build a three-dimensional solid model of deepfoundation pit,the author analyzes the soil around foundation settlement, settlementand columns supporting structure made the top horizontal displacement settlementnumerical simulation analysis, simulation results is basicly the same with monitoringresults,it\reflects the pit deformation characteristics to some extend. 3With the method of gray system theory, the metabolic GM (1,1) model.thetraditional GM (1,1) model is considered the first point after definite solution ofdifferential equations least squares fit of the curve, from the theoretical prediction,oldest b data is important which discrepancies in the actual situation. Therefore, thisarticle selects the last fixed-point fitting least squares curve, to establish appropriatemetabolic GM (1,1) model. Among all the monitoring data obtained,the authorselecte measurement points JC9supporting structure at the top level of the cumulativevalue of displacement monitoring study were using traditional GM (1,1) model andimproved metabolic model predictions. Predicted results were compared with theactual monitoring data, the results show improved metabolic models predict higheraccuracy, better applicability in practical engineering.