The Study And Engineering Application Of Deep Foundation Pit Deformation Monitoring System

With the continuous development of modern city of all kinds of buildings and the size of the foundation pit the development towards the direction of the large and deep, thus put forward great challenge for safe construction. In the process of deep and large foundation pit construction, the reasonable choice of foundation pit deformation monitoring project is particularly important, so the study of deep foundation pit deformation monitoring system is becoming more and more attention by all of us on abroad. But, in china, the research relatively late in the deep foundation pit, it was not until1999, we held its special meeting to the research field of deep foundation pit. The theoretical research relatively lags behind the practice and engineering experience is not rich also, coupled with lack of the management level and construction experience, so engineering accidents caused by far more than the developed countries during the period of deep foundation pit engineering construction. Therefore, this article through consulting a large number of relevant documents researches the deep and large foundation pit from the following aspects:First of all, I introduce the foundation pit deformation involved in geotechnical deformation theory and the mechanism of seepage in rock mass deformation. Second, the paper analyzes the forms of the deformation of foundation pit during excavation process:One, at the beginning of the foundation pit excavation, foundation pit has elastic uplift and the middle has the largest elastic uplift at the bottom of the foundation pit. Two, with the excavation of foundation pit, the ground settlement around the foundation pit increases. Three, with the excavation of foundation pit, the horizontal displacement and vertical settlement of foundation pit supporting structure increases.Later, I analyses the monitoring design system of deep foundation pit and more detailed discusses the principle of foundation pit monitoring system layout, the determination of monitoring items and monitoring instruments and monitoring method of choice. Due to the diversity of the monitoring data, then I discusses the monitoring method of data processing, such as error analysis and the principle of adjustment. Finally, the paper takes mathematics method of evaluation and analysis for monitoring data and determines the alert value of various monitoring items.At the end of the paper, combined with Dalian Hang Lung plaza foundation pit excavation project, the paper analyzes in detail implementation process of the whole monitoring system. Through the above theoretical operation method, first of all, using ANSYS numerical analysis was carried out on the excavation of a cross section. By analyzing the results compared with the actual monitoring data, which assesses safety and shortage of the foundation pit engineering and provides strong guarantee for the safety of the foundation pit construction.