Deformation Detection and Estimation of Pagoda Based on Multilayer Central Points’ Fitting

Abstract:

This paper presents a practical novel approach for tilt measurement of ancient pagodas and the criterion quality evaluation. Due to the characteristics (multieaves, dougong and vague edges) of ancient pagodas, it is difficult to select measurement points. The coordinates of the central point of each floor of the ancient pagoda structure is estimated by using the method of ellipse fitting. During the process of fitting space axis of the pagoda, the method of total least square is applied to calculate the result. Besides the inclination and twist of each floor is calculated in order to assess the quality of the pagoda in a comprehensive way. This method is more accurate and detailed than the current tilt measurement method which determines the deformation and inclination of tower structures by the ratio of relative displacement of the tower’s base and top and the height of the tower.