Study on local uplifts near border of surface subsidence basin caused by mining excavation

To study the uplift phenomenon near the border of surface subsidence Basin and its influencing factors, field measurement and numerical simulation wer e conducted to study the uplift phenomenon near the border of surface subsidence basin under different bedrock thickness and lithology conditions.On the basis of over burden migration structures after mining excavation, a mechanical model based on the elastic foundation beam had been established to study the deformation character istics of strata in different mining and geological conditions, the mechanism of uplifts of surface and its judgment basis were also analyzed.The results showed that the most important factors affecting local uplifts near the border of surface subsidence basin were mining influence and geological condition. The amount and rate of integr al subsidence increased as the thickness of bed rock or hardness of the roof decreased.It was hard to see the uplift phenomenon as the thickness of the bedrock was to 0 large or the hardness of the roof was too high. Only when the thickness and Protodyakonov coefficient of bed rock were in a certain range, the local uplift phenomeno n could appear at the border of basin. In addition, the amount of uplift was inversely proportional to thickness of bed rock and proportional to Protodyakonov coefficient of roof strata.