THE PROPOSAL ABOUT EFFECT ON A DECREASE IN THE GROUND VIBRATION OF THE COMPOSITION ISOLATION WALL OF CONCRETE AND EPS AND THE APPRAISAL METHOD

Abstract

The hollow composition isolation wall made of concrete and EPS (Expanded Poly Styrene) was investigated to reduce transmission of vibration. A full-scale experiment was conducted with the wall. The vibration was given by free falls of a weight to simulate vibration from construction works and vehicles. Aa for effect on a decrease in vibration, including embedded depth of the composition isolation wall showed the effect of 4.5dB on the average even in about 1/4 of the wavelength 3Hz in the nearby low frequency number of vibration. And, it was found that the range where the diffraction from the end part of the isolation wall didn't affect was within θ=70° behind the wall. Based on the results, a simple method to estimate the reduction of vibration by the composition wall was proposed. The proposed method estimated the vibration reduction well, and it was found that the method can be used to quantitatively estimate the efficiency of composition isolation wall.