PURPOSE: To enable the improvement of strength and stability of a fill-up ground, by a method wherein a dry mortar is positioned between the nip formed by bankings, and simultaneously, reinforcing steel material is embedded in a dry laminar mortar.

CONSTITUTION: In case a ground is formed by conducting a banking, a dry mortar 2 is located in a laminar manner between nip formed by bankings 1, and simultaneously, a reinforcing material 3 is embedded in a dry mortar layer 2. The dry mortars 2 are positioned in a multilayer between the nip formed by the bankings 1. The dry mortar 2 is prepared such that fine aggregates, being 7W12 times as much as a binder, is mixed in the binder containing blast furnace cement and hemihydrate in ratio of 80W95% the former to 20W5% the latter. This causes monolithical curing of the dry mortar 2 and the reinforcing steel material embedded therein to form a mortar beam which results in producing an effect to stabilize the banking.