Abstract: The deformation induced by mining residual cavities and fractures is a main reason causing damages to buildings in mining-induced subsidence area. In order to study the deformation characteristics of the building foundations in mining-induced subsidence area, by analyzing the distribution of the additional stress and the mining residual cavities and fractures in mining-induced subsidence area, the deformation zone of the foundations in mining-induced subsidence area has been studied. Based on the analysis of the detection for mining residual cavities and fractures and the distribution of the additional stress in the foundations, the deformation zone of the foundations in mining-induced subsidence area is above the soil depth, at which pz=0.1σz. However, when there are some mining residual cavities and fractures near this depth, the deformation zone in foundations should include mining residual cavities and fractures zone and its above area. According to the location of the buildings in Yima mining- induced subsidence area, the residual cavities and fractures zones under building foundations in mining- induced subsidence area have been detected by high density resistivity tomography method. In addition, the main reason causing damages to buildings has been demonstrated by analyzing the distribution of the stress and the deformation zone in foundations. The analysis of the distribution of the additional stress and the mining residual cavities and fractures zones also indicates that a proposed new structure will be affected by the deformation induced by the residual cavities and fractures zone, therefore, the new building foundation should be reinforced or changed.

Key words: mining-induced subsidence area, foundation, deformation, additional stress, high density resistivity method