Dynamic active thrust from c–ϕ soil backfills

This technical note presents an analytical derivation of the expression for the total dynamic active thrust on a retaining wall from the c–ϕ soil backfill considering both horizontal and vertical seismic coefficients. The derivation is based on the Coulomb sliding wedge concept, and it considers tension cracks, wall adhesion, and surcharge in order to make the expression useful for practical applications. It is found that the special cases of the general expression result in the expressions for total static and dynamic active thrusts presented by earlier researchers for different field conditions of soil backfills with and without seismic loadings.