AN OPTIMIZATION MODEL FOR PARALLEL HIGHWAY NOISE BARRIERS

The concept of noise reduction by means of a single barrier is well understood, and the technical methods involved are well developed. But the problem of parallel highway barriers on both sides of a proposed facility has not been resolved to any practical extent, specially the problem which involves barriers of different heights.;An optimization model consisting of a parallel-barrier algorithm and an nonlinear programming model is presented. The parallel-barrier algorithm is developed by consolidating the previous works on parallel barriers theory and extending from the Federal Highway Administration Highway Noise Prediction Model to account for the analysis of parallel-barrier problem. The nonlinear programming model is developed by using the parallel-barrier algorithm to account for the design of parallel highway barriers with different heights. Application examples and validation studies are conducted by a computer program coded from the algorithm and the direct search method of the nonlinear programming techniques. Results from the validation studies show that the model presented is suitable to conduct the parallel-barrier analysis and optimum barrier design with different heights.