Response of different machine foundation shapes resting on dry sand to dynamic loading

Abstract EN

In this paper, the effect of footing shape resting on dry sand when subjected to machinedynamic loading is experimentally investigated.

A laboratory set-up was prepared tosimulate the case at different operating frequencies.

Nine models were tested to examinethe effects of the combinations of two parameters, including different frequencies of (0.5, 1, and 2 Hz) and different footing shapes (circular, square and rectangular).

The testswere conducted under a load amplitude of (0.25 ton) using sand with medium and denserelative densities corresponding to (R.

D.

= 50% and 80% ) having unit weights of (17.04and 17.96 kN/m3) respectively.

A shaft encoder and a vibration meter were used tomeasure the strain and amplitude displacement, while the stress in the soil at differentdepths was measured using flexible pressure sensors.

It was found that the shape offooting has a considerable influence on the bearing capacity of the supporting soil underdynamic loading.

For instance, the strain of dry sand under a circular footing was nearly(41% ) higher, the amplitude displacement was nearly (17% ) higher, and stress wasnearly (12% ) higher than square and rectangular footings, under the same conditions.