老采空区上方地表变形是一个具有复杂性、突然性和长期性等显著特点的非线性过程。在老采空区上方建设生活或服务设施时,必须对老采空区上方地基稳定性和残余变形情况进行评价和预测。基于多尺度经验模态分解(EMD),提出了老采空区上方地表建筑物稳定性分析及预测新方法。通过实例研究,证实采用多尺度经验模态分解可获得老采空区上方地表建筑物的动态变形细部信号。对各分解尺度进行分析能更准确有效地评价原始数据所反映的建筑物变形特征和进行变形机制研究。同时,实例计算也证实,采用考虑多尺度特征的预测模型可获得比传统方法更优的变形预报精度,为更科学地评价老采空区建筑物稳定性提供理论依据。
Deformation of ground surface above old mine goaf is a complex nonlinear process, which has complex, sudden, and long-term features. The foundation stability and residual deformation must be evaluated before building life or service facilities above old mine goaf. A new method is put forward for stability analysis and evaluation of buildings above goaf by multiscale decomposition using empirical mode decomposition(EMD) method. Trough case study, detail signals of dynamic deformation of buildings above old mine goal are obtained using multiscale empirical mode decomposition method. Decomposition scales are analyzed so as to evaluate the deformation characteristics reflected by original data and research the deformation mechanism effectively. Precision prediction for deformation is obtained by multiscale prediction model which is better than traditional method. This prediction model can provide a theoretical basis for stability evaluation of buildings above old mine goaf.