Static Monitoring And Dynamic Measurement Based On 3D Laser Scanning Technology In Geotechnical Engineering

Monitoring is an important prerequisite for ensuring the safety of all kinds of engineering.With the rapid development of China's economy and construction,the requirements for engineering safety and construction accuracy are constantly improving,and the monitoring conditions are becoming increasingly complicated.Conventional displacement monitoring methods such as total station,etc.are increasingly unable to meet fast frequency and high intensity monitoring.In addition,a large number of geotechnical engineering will be affected by dynamic disturbance during construction and operation.Dynamic monitoring of engineering is becoming more and more important.Therefore,it is urgent to establish a non-contact,wide range,fast dynamic and static monitoring method.3D laser scanning technology has the advantage of non-contact,large surface displacement field acquisition,and has been widely applied in geotechnical engineering monitoring.This paper focuses on the application of 3D laser scanning technology in geotechnical engineering dynamic and static monitoring.In the aspect of static monitoring,the advantages of non-contact and large range acquisition of surface displacement field are made full play.Combined with the traditional monitoring means,a high efficiency,high speed,high speed and high speed based on 3D laser scanning technology is established,and the static monitoring and stability evaluation method of digital archiving cannot be established.The limitations of visualized archives.In order to discuss the application of this technology in dynamic monitoring,the iterative least square method is used to restore the dynamic cloud point,and the fitting algorithm is verified by the experiment of water transport sand square.The main work and conclusions are as follows:?1?through experiment,the system error index of 3D laser scanner is obtained,and the error source and influence are analyzed according to the obtained index,which makes the conclusion of this paper more valuable;?2?Iterative least square method is used as the basic theory of point cloud fitting and deriving the applicability of the method through the mathematical formula.The point cloud is filtered by using the curvature and elevation of the surface of the object.Kriging interpolation method is used to make up the hole caused by the filter and extract the topography of the slope.Based on static monitoring theory,the reduction method of scanning point cloud under dynamic perturbation is proposed.?3?A new stability evaluation system was established by using 3D laser scanning technology to monitor the surface deformation of a side slope of Zhang-Cheng expressway.The 3D laser scanning technology can continuously monitor the feature points and analyze the deformation field and provide the 3D model and displacement cloud map by generating the grid model and extracting contour lines.The point cloud data is used for rapid modeling,deep deformation analysis and calculation of safety coefficient in FLAC^3D.Finally,the stability of the slope is analyzed comprehensively with the results of surface deformation monitoring and deep deformation analysis.The results fully demonstrate the feasibility of 3D laser scanning technology in long-term and high-precision monitoring.?4?We did a series of experiment on shipload measurement.Through the static measuring experiment,the error of 3D laser scanning system is found to be 2.46%which satisfy site requirement.But the point cloud under dynamic disturbance must be calibrate to satisfy the limit.Then demonstrate the feasibility of polynomial surface fitting by fitting the point cloud under static condition.The result after fitting is 99.80%similar to it before fitting.Finally,the error is corrected by the polynomial surface fitting which decreases to 2.97%from 5.37%which satisfy the 3%site requirement.The experiment demonstrates the applicability of this method in dynamic measurement.Compared with traditional measuring methods,the 3D laser scanning technology has the characteristics of high precision and high efficiency and has the ability to obtain the details of the 3D space of the scanning object and digitize the file.