Research on Deformation Monitoring and Analysis Method of Ancient Architecture Based on 3D Laser Scanning——Taking the Deformation Monitoring of State-level protection Units Along Suzhou Rail Transit Line 4 as an Example

3D laser scanning is a rapidly developing and mature technology in obtaining mass high-precision point cloud of ground.As a traditional measurement work,deformation monitoring has developed to the present,need more and more new technologies to be integrated.Especially for the deformation monitoring of historical ancient architectures,3D laser scanning technology can be better applied when traditional monitoring methods are difficult to unfold.Taking the 3D laser scanning deformation monitoring of the two stone structures named Lingxingmen and Canglangting along the No.4 line of Suzhou Rail Transit as a research example,the method of deformation analysis based on linear or planar features extrated from point cloud data is discussed,and the adjustment model using total-least squares adjustment method is improved,in order to improve the reliability of the deformation analysis.