Double-parameter foundation beam modal of overlying thin rock stratum under loose layers grouting mining

Strata movement of drilling grouting is distinctly different from that of traditional caving mining, especially for overlying thin rock stratum. Considering the horizontal shear transfer of foundation, a mechanical model of overlying strata movement was established using the theory of Pasternak double-parameter foundation beam. The deflection and internal force equations of rock beam were derived, and the influence mechanisms of grouting material parameter were discussed. The results showed that the thickness of layer grouting was the key influential factor than the foundation modulus coefficient and grout diffusion radius. The comparison with the theory of Winkler elastic foundation beam also showed that double-parameter foundation beam method is more applicable to reinforced strata.