One-dimensional,semi-analytical solution for time-dependent behaviour of a seam

The paper provides a one-dimensional, semi-analytical study of face advance in a coal seam assuming a Bingham type of material model. The changes in vertical stress and deformation in the seam due to change in the geometric configuration of the excavation are analysed. The general analytical formulae defining stresses and strains for an arbitrary time instant i Δt(i = 1,2,…) are derived, and the size of the viscoplastic zone near the opening and its evolution with time are determined. The influence of the seam extraction rate on the stability of the seam and rock burst occurrence is discussed in the light of the developments presented in this paper.