A simplified approach is proposed to reduce computational cost in conventional parametric optimization of open or in-filled trenches isolating rail-induced structural vibrations. In particular, it stands on an FEM-bas...A simplified approach is proposed to reduce computational cost in conventional parametric optimization of open or in-filled trenches isolating rail-induced structural vibrations. In particular, it stands on an FEM-based hybrid optimization scheme consisting of multiple two-dimensional models and one global three-dimensional model. First, representative planar FE （finite element） models orthogonal to the rail-direction are identified. For each section, the sensitivity of the trench＇s design parameters, such as geometry and backfill materials, to its vibration screening effect is respectively evaluated. Second, a full trench along the rail-direction is determined according to the two-dimensional optimization result. The global performance of the optimal trench is simulated in the three-dimensional model and finally becomes a reference for practical design. By optimizing the design parameters of a case study project, the proposed approach has shown the capability of solving complex engineering problems at a minimum computational cost, therefore is applicable in determining design parameters of rail-induced vibration isolation trenches.展开更多
文摘A simplified approach is proposed to reduce computational cost in conventional parametric optimization of open or in-filled trenches isolating rail-induced structural vibrations. In particular, it stands on an FEM-based hybrid optimization scheme consisting of multiple two-dimensional models and one global three-dimensional model. First, representative planar FE （finite element） models orthogonal to the rail-direction are identified. For each section, the sensitivity of the trench＇s design parameters, such as geometry and backfill materials, to its vibration screening effect is respectively evaluated. Second, a full trench along the rail-direction is determined according to the two-dimensional optimization result. The global performance of the optimal trench is simulated in the three-dimensional model and finally becomes a reference for practical design. By optimizing the design parameters of a case study project, the proposed approach has shown the capability of solving complex engineering problems at a minimum computational cost, therefore is applicable in determining design parameters of rail-induced vibration isolation trenches.
