Longwall Mining Surface Subsidence Trough

Mining & Petroleum Engineering

How It Works

Underground extraction of coal or mineral seams via longwall caving causes overlying strata to collapse into the mined void, propagating vertical displacement to the ground surface as a continuous subsidence trough. The surface settlement profile is modeled using Gaussian influence functions and the angle of draw, governing horizontal tensile strains and ground curvature.

Governing Equation
S(x) = S_max · exp[-π · (x / r)²]  |  ε(x) = dU/dx = -B · (d²S / dx²)