Evaluation Of Outpatient Building Deep Foundation Pit Slope Stability In Guang’anmen Hospital

With the rapid development of city construction, the high-rise buildings and thefull use of underground space promote the development of deep foundation pit, whichleads to a large number of deep foundation excavations. At present, the deepfoundation pit engineering has been gradually showing the characteristic of increasingnumber, larger scale, deeper and more difficult in technology. Because of perplexinggeological structure, uncertainty of soil properties and lack of effective design andconstruction management, collapse of deep foundation pit slope occurs frequently.Serious collapse will lead to great economic loss and bad social influence. So it hasimportant practical significance to study the stability of deep foundation pit.Firstly, this dissertation discusses the significance of the topic and the status offoundation pit research at home and abroad. After that, the structure type, slopeprotection principle and design calculation principle of pile-anchor supportingstructure are presented.Secondly, the classification of safety level of deep foundation pit is introducedaccording to different standards. The comparative analysis is done for someevaluation methods of the deep foundation pit slope stability. A new method has beenpresented, which uses the central difference method to analyze the pile bendingmoment according to the data of pile deformation which is monitored by inclinometer.The theory basis and the advantage of the evaluation method are explained. There is adetailed analysis of the calculation principle, calculation steps and applicability in thisdissertation.Thirdly, the factors affecting the calculation results are analyzed according toinclinometer data. These factors mainly include measurement error, design scheme offoundation pit and the parameters selected for calculation. At the same time, thecorresponding solutions are put forward.Finally, the deep foundation pit project in Guang’anmen hospital is taken as anexample. The excavation and support are analyzed by FLAC-3D software through theactual monitoring data which is monitored during the construction process. The comparative analysis of monitoring results and the numerical simulation results isdone and the reliability of numerical simulation analysis is verified. At the same time,on the basis of the central difference method mentioned above, the monitor data iscompared with the elastic method. According to the standards for foundation pitdeformation and internal force of supporting structures, the alarm value ofdeformation and moment are confirmed. The method of determining the safetysituation of foundation pit by the moment of supporting structures is feasible.