Research On The Diagnosis Methods In System Of Automatic Monitoring Horizontal Displacement In Underground Engineering

Monitoring of horizontal displacement in underground engineering is an importantpart of monitoring of engineering. The cycle of underground engineering is very longand the amount of monitoring results in the cycle is very huge. Most importantly, themonitoring results of construction process are time-sensitive. Based on previousexperience of research and development, the remote and automatic monitoring systemhas been optimized and it is applied to practical projects.The work and conclusions in the paper are as follows:1. The automatic monitoring system has been optimized in the paper. Thefunction such as data acquisition, data processing, data transmission, deformationprediction and alarming has been improved. Series of Verhulst models has been addedinto diagnostic module as well as finite element method.2. The theory and development processes and the characteristics of time seriesmodels such as GM(1,1) model, Verhulst model, BP neural model has been depthstudy in the paper. Based on the Matlab, models mentioned above have beendeveloped, and the GM(1,1)-Verhulst combined model and Verhulst-BP combinedmodel had been established according to the variance portfolio and error correction.3. The time series models are applied to two practical projects. One of practicalprojects is Tianjin Jinyuhuayuan residential project, the other is Rongchuang project.The time series models are established to forecast horizontal displacement ofsupporting structure in the near future, the feasibility of time series models indeformation prediction and diagnosis model has shown in the paper by comparisonbetween the true value and the predictive value; the combined models have higheraccuracy than pure model. The conclusion that the number of time series modelsshould be bigger is drawn.4. Many finite element models have been created by ABAQUS. They aredifferent in the depth of excavation and pit angle and the way of excavation. Theinfluence scope for the horizontal displacement of pies with different angles has beendefined by the ratio of horizontal displacement; the curves of horizontal displacementin pits with different construction methods were shown. The features of differentconstruction methods were gotten by the contradistinction between curves. It isobvious that the finite element models have an important significance in the system of automatic monitoring horizontal displacement in underground engineering.