Analysis of Building Safety Affected by Residual Cavities in Mining Area

摘要

Deformations induced by the unstability of residual cavities have seriously harmed the safety of the building in mining area. In order to analyze the influence of the residual cavities on the buildings, an effective method called high density resistivity tomography geophysical technology has been used. Then the residual cavity zones and their horizontal locations and vertical depth have been obtained. Based on the detection results and related theory, the mechanism of deformation and reasons of building damage in mining overburden residual cavities under construction load have been analyzed. According to the locations of the residual cavity zones and the distribution of the additional stress of buildings, the safety of buildings affected by residual cavities has been investigated. The calculated-depth of foundation deformation is suggested to be above the depth where the ratio of additional stress p_z to the soil gravity stress a_z is 0.1(p_z=0.1σ_z). If the depth of the residual cavities located beneath this calculated-depth, the foundation deformation range should be chosen above the depth of residual cavity zone. The method and analysis process proposed in this research will provide an important reference for safety evaluation of the buildings located in the areas affected by mining residual cavities.