Abstract:Behavior of spread foundation on aeolian sand with geo-grids subjected to pressure force is studied with model tests. The properties of direct shear friction and pull-out friction actions are studied. Fourteen types of geo-grid reinforced aeolian sand are selected in the model tests to show that the pressure-bearing capacity of geo-grid reinforced aeolian sand is 11.0%~453.0% higher than that of the unreinforced. The pressure-bearing capacities of rectangle box geo-grid and two layers of geo-grid are higher than those with other types of geo-grids for the same embedment,and the anti-displacement property is improved. It is shown that the mechanism of pressure-bearing capacity is due to the compression of sand,shearing resistance of sand,the mutual frictional action,and restrain action between geo-grids and soils. The formula for calculating pressure-bearing capacity of spread foundations with reinforced aeolian sand is derived and the calculated results agree well with those measured. The rectangle box geo-grid and two layers of geo-grid are shown to be effective to reinforce the aeolian foundation.