The Action of Vibrating Foundation on Adjacent Static – Load Foundation Having Rectangular Shape

This paper presents an experimental study on the dynamic response of the rectangular foundation, under effect of dynamic load which results from an adjacent footing called (the source of vibration), having square shape and excited by a well-known source of vibration put on the top it. The purpose being to study the effect of dynamic motion on a nearby foundation called a second foundation. Both foundations are founded on collapsible soil (gypseous soil) with a content of gypsum 60%. The research is conducted in dry and soaked conditions with a large experimental program. The first basis (source vibration) and the second footing are made out of steel, respectively in the sizes (80x80x40), (160x40x40) mm with (L/ B= 4). After that the soil had been prepared in layers in steel containers with (1000x 500x500) mm, then the two foundations positioned centrally over the ground. The first footing excited by the rotating mass type mechanical oscillator to generate vertical harmonic loading, produces a comparable impact of dynamic loads and the second footing is loaded with only static weight under dynamic excitement. The tests were conducted under dynamic response for three frequencies (10, 20, 30) Hz, Displacement amplitude and acceleration of the second foundation were determined, at a different distance between the foundation (2B, 4B, 6B). The results have shown that, when the distance between the foundation increases, the amplitude and the acceleration for the second foundation decreased. Furthermore, the value of these parameters at dry state is higher than their value at soaked state.