The Stability Analysis Method And Applied Research Of Deposition Monitoring Network Of Deep Foundation Pit

With the development of high-rise buildings and underground engineerings, deepfoundation construction is generally started.Now, the number of deep foundation pit issharp increasing, in the design and construction experience gradually rich at the sametime,however,the foundation pit accident continue to occur.According to incompletestatistics, from 2000 to 2010, between 10 years , the 37 large and medium-sized citiesof our country has occurred more than 100 major excavation safety incident causedsignificant damage to the national economy and people’s lives and property.Theaccident of the Pit caving form, the supporting structure damaged collapsed and thesurrounding area of landslide, cracking or collapse of the adjacent underground basedeflection or destruction, excavation of the surrounding road, near the buildingcracking or even collapse.Statistical analysis the cause of the accident, the vastmajority of accidents are directly related to the monitoring is not in place or warningare not allowed.Therefore, the deep foundation for effective monitoring, scientific andtimely processing of monitoring data, information construction is necessary.Subsidence monitoring in order to obtain the displacement of the verticaldirection of the surface or surrounding buildings, which is the focus of deformationmonitoring and subsidence monitoring should create a subsidence monitoring networkmonitoring network stability analysis is the basic premise and an important part of thesettlement analysis. Based on a subway deep foundation settlement monitoring project,analysis and research on some important issues in the analysis of the subsidencenetwork stability. The main content is as follows:(1) Through the analysis of indirect adjustment, the rank defect free networkadjustment, the proposed stable adjustment principle, given the actual choice of thereference system and two commonly used adjustment datum transformation method,and derive another benchmark based on the benchmark solution to transform;(2) Steps and the classical method of stability analysis, in which the average gapmethod and for the overall test for single-point test "T-test method" for a moredetailed analysis, and briefly describes the tolerance test method(3) In view of the average gap method + unstable point search methoddisplacement analysis of pattern of excessive, given a method——“Hybrid stabilitytest method ", It is one that enhances the efficiency of calculation of a relatively smallamount of analytical methods;(4) Using C + + language preparation of an adjustment program, the programusing indirect adjustment Rank Defect Free Network Adjustment intended Stable Adjustment and different adjustment calculated.And then using MATLAB softwareprogramming on the stability of data analysis, in order to make the results moreintuitive, and the preparation of a vector displacement map program.The original needto manually compute-intensive process, the computer will be able to complete thestability analysis. Stability analysis of the use of engineering practice, saving a lot oftime, and the monitoring network is easy, simple(5) The monitoring project of the deep foundation of a subway monitoringnetwork observation data processing and analysis, a data analysis used to test thetheory, methods and formulas.And net shape to make a change, analog are likely tomove the case at all, using observational data of two stability analysis of themonitoring network, and the aforementioned preparation procedures applied to theinstance for the program unreasonable athave made changes, and achieved goodresults.