Design And Research On Horizontal Movement Automatic Monitoring System Of Foundation Pit

With the development of urbanization and large-scale infrastructure construction,the development of underground space has been brought into full swing.When the development of large scale deep foundation pit,real-time and reliable monitoring and prediction of construction safety are needed to be provided.For a long time,pit horizontal movement data acquisition is mainly rely on manual measurement or fixed inclinometer measurements,which are difficult to meet the need of the pit horizontal movement information in large-scale infrastructure;the former is lack of stability,slow and can not be measured in real time,the latter is expensive and inconvenient to install which make it is difficult to promotion in large scale.So,it is of great significance to study how to obtain the horizontal movement information of the foundation pit accurately,in real time,and at low cost.The object of this research,the deep horizontal movement of foundation pit refers to the deformation of the soil around the foundation pit at various depths,it is the most direct and most important parameter to measure the stability of foundation pit.In view of the fact that in the aspects of real-time,economy and systematization,current horizontal movement measurement technology of foundation pit can not meet industry needs at present and in the future,this paper puts forward a set of solutions to realize the accurate,real-time,low cost and network monitoring of the horizontal displacement of foundation pit.Firstly,this paper reviewed the development in measurement technology of horizontal movement,described the research results at home and abroad in detail,and analysis of the advantages and disadvantages of current technology,fully tap the measurement method mentioned in the literature value.Then,from the aspects of realization of horizontal movement automatic monitoring and optimization of measurement data,the operation principle of the whole system,the design details and the optimization scheme of data processing algorithm are discussed detailedly in this paper.The realization of automatic monitoring is based on the acquisition,transmission and display of horizontal displacement data,introduces the principle of measuring horizontal movement of foundation pit,optimization on the structure of inclinometer sensor,the structure design of small host,hardware and software design of sensor and host,Zigbee based site networking scheme,and the design of monitoring system software.About the pant of data processing optimization,to deal with the noise problem of measurement data,it proposes a processing method basedon the limit average filter and Kalman filter;in order to fully excavate the hidden foundation deformation information in the measured data,the method of three spline interpolation is demonstrated and selected on data processing.Finally,through a long time high density measurement of a complex foundation pit which located in the Pearl River Estuary Area,the reliability of the whole system has been tested;At the same time,by comparing with manual measurement data and traditional data processing methods,the validity of the data processing scheme used in this system has been verified from the point of quantification.