چكيده به لاتين
In the present study, by using full-scale field experiments and three-dimensional finite element numerical model built with LSDNA software, the performance of wave barrier trenches in both empty and in-filled trenches with different crumb rubber percentages has been studied. The performance of sand rubber mixture as filler materials in reducing vibration has also been investigated. Since studies have so far performed mainly limited to two-dimensional numerical modeling and the results of these modeling have rarely been validated, this study attempted to investigate the parameters affecting the performance of trenches using the results of full-scale field experiments and numerical modeling and parametric analyzes. For this purpose, the numerical model was validated by field experiments, followed by parametric numerical analysis in the elastic strain range. The amount of vibration reduction, optimal mix of sand and rubber, the optimal source-barrier distance and the optimal dimension of the trench were the studied parameters.
Prove the close performance of a SRM filled-trench to the empty trench that has been the subject of much research to find such materials, and prove the effectiveness of these materials in reducing vibrations up to 77% was the results of present study. Based on the results, the optimum depth and length for deep trenches for controlling vibrations in both horizontal and vertical directions were proposed as 5λR and 8λR, respectively. It was also found that the width and distance of the trench to the loading location were only effective in shallow trenches and their effect will decrease with increasing depth. Also, the width of trench impact in deep trenches is equal to the width of the trench and is up to 8λR behind it. On the other hand, the most important factor in effectiveness of the trench is the impedance coefficient, which, based on the obtained results, the final limit of effect of this parameter is 0.1. Reducing the impedance above this level will have little effect on trench performance. Coefficients of -0.31 and -0.51 in vertical vibrations and -0.46 and -0.53 in horizontal vibrations to correct the empirical formula proposed by Sikia et al was also one of the findings of this study.
