Dynamic response of a footing adjacent to dynamically loaded footing on gypseous soil

Abstract

This paper presents an experimental study on the dynamic response of a circular foundation, underneath the have an impact on of a dynamic load that outcomes from the placement of a neighbouring footing said as (vibration source), having square-shaped and excited by way of a known source of vibration placed on top of it. The cause is to evaluate the effect of dynamic motion closely by group called the second foundation. Both foundations were founded on collapsible soil (gypseous soil) with a content of gypsum 65%. The research is conducted in dry and soaked conditions with an oversized experimental programme. The first base (source vibration) and also the second base are made of steel, with the size of 80 × 80 × 40 and the circular shape of 80 mm diameter. Subsequently, the soil had been prepared in layers in steel containers with 1000 × 500 × 500 mm, then the two foundations positioned centrally over the underside. The first footing excited by the rotating mass type mechanical oscillator to come back up with vertical harmonic loading, produces a related have an impact on of dynamic loads and also the 2nd base is loaded with only static weight under dynamic excitement. The checks are conducted beneath dynamic response for 3 frequencies (12, 18, 24) Hz, Displacement amplitude and acceleration of the 2nd foundation are examined, at a special distance between the inspiration (2B, 4B, 6B). The results have shown that when the space between the inspiration increases, the amplitude and also the acceleration for the second foundation decreases. Furthermore, the value of these parameters at dry condition is larger than their value at soaked states.