Abstract: In recent years, there have been an increasing number of high-rise heterogeneous buildings in coal mining subsidence areas. Traditional point measurement methods can no longer meet the requirements for the deformation monitoring accuracy, mainly due to the following two reasons: ①It is not easy to select feature points; ②It is difficult to accurately measure the feature points. Regarding these two problems, based on point cloud data and by using the target central axis fitting method, this paper proposes a tilt measurement method for high-rise heterogeneous buildings based on surface mapping. Verified by practical examples, the tilt obtained by this algorithm for the structures is 22.97 mm/m, while the tilt obtained by the traditional measurement method is 21.53 mm/m, with a relative error of 6.9%, which meets the accuracy requirements for tilt measurement. The research results can provide technical support for the rapid and efficient tilt monitoring of similar high-rise structures in mining areas.

Key words: high-rise heterogeneous buildings, tilt measurement, coal mining subsidence area, 3D laser, least square method