Optimisation of Support Performance Through Consideration of the Pressure/Convergence Ratio

SUMMARY The Paper considers the ratio of pressure increase per unit of convergence in the legs of a powered support to be a measure of its sensitivity to convergence. This sensitivity, which should be maximised in the interests of strata control, is shown to depend on the load bearing properties of the foundation underneath the support base. Methods, including the manipulation of setting and yield pressures, are suggested for modifying these properties in order to generate high sensitivities.