Research On Slope Deformation Technology Based On GNSS-RTK

Geological disasters caused by slope deformation,such as landslides,mudslides,falling rocks,etc.,cause a large number of personal injuries and property losses throughout the world every year.The main monitoring measure for slope deformation is to monitor the displacement of the slope body.The monitoring accuracy of this displacement must reach the centimeter or even millimeter level.The use of traditional monitoring technology is not only expensive and not real-time.In order to make up for the shortcomings of traditional monitoring technology,this paper focuses on the GNSS-RTK(Global Navigation Satellite System-Real time kinematic)technology,which is used to achieve high-precision and lowcost slope deformation monitoring,and design a set of real-time monitoring capabilities.Slope deformation monitoring system.The main research contents and innovations of this article are as follows:(1)This paper completes the derivation of the BDS-GPS dual-mode single-frequency algorithm,and deeply analyzes the main difficulties of GNSS applied to slope monitoring,and systematically analyzes the main reasons that affect the accuracy of slope monitoring.A fixed algorithm for fast ambiguity in slope monitoring is proposed.This algorithm can significantly reduce the number of floating-point solutions,and to a certain extent can improve the ambiguity fixation rate and positioning accuracy.(2)In order to verify that low-cost hardware devices can be used for slope deformation monitoring,this paper tests the positioning performance of GNSS antennas,low-cost GNSS receivers,and different baseline lengths.And set up a simulated slope displacement device in the laboratory,and use the fixed algorithm of fast ambiguity and low-cost hardware to test the monitoring accuracy under different deformation displacement speeds.At the same time,in order to further analyze the data collected by low-cost hardware,a GNSS data postprocessing analysis software was developed using MATLAB,which can realize RTK positioning and error analysis.(3)This paper has completed the design of the GNSS-RTK slope monitoring system scheme,which includes the multi-threaded development of the RTK solution program,and proposes two RTK solution solutions: local solution and server solution.In order to improve the reliability of the system,it is proposed A two-layer baseline monitoring program was developed.Then,in view of the situation that a small amount of outliers(large errors)will inevitably appear in the positioning results in a complex environment,a real-time outlier proposal procedure is proposed.Finally,two practical application examples of river slope and highway slope are described.The design of GNSS monitoring station and data transmission network are completed for the river slope,and the static monitoring results are analyzed.The monitoring accuracy error is obtained,and the horizontal direction is 2.1.mm,the elevation direction is 4.6mm;the design of the monitoring station and base station is completed for the highway slope,the RTK server solution mode is designed,and real-time data is collected to complete the analysis of the improved ambiguity algorithm.Practice has proved that the proposed slope monitoring is fast and fuzzy The degree of algorithm is helpful to improve the fixed rate of ambiguity and positioning accuracy.