This study proposes the surface-perforated mortar (SPM) to mitigate railway noise. As one of most emerging noise problems, deteriorates quality human lives. paper investigates sound absorption performance SPM and it is compared that porous concrete which has been adopted as a potential solution for The effects hole size depth, surface porosity on examined using an in-situ test results explain m...

Abstract The crash box’s internal structure can be designed to absorb more energy in a significant way. Using the finite element method, this paper investigates with negative Poisson ratio and self-torsion effect. arrangement combination of eight structures have torsional that is negative. optimal absorption LCHC-B structures, as determined by simulation analysis, results an excellent performan...

Abstract In this paper, a carbon nanotubes/polyurethane resin (CNTs/PUR) honeycomb composite absorbing material was prepared, and the influence of content nanotubes on performance single-layer double-layer materials investigated. The mechanical properties are discussed. core compounded together by impregnation method to form CNTs/PUR material. microstructure shows that uniformly dispersed in wa...