GFRP posts for railway noise barriers – Experimental validation of load-carrying performance and durability

As part of a 15-year railway noise remediation plan, 300 km of noise barriers will be installed in Switzerland over the next few years. To enable pultruded glass fiber-reinforced polymer (GFRP) materials to be used for the noise barrier posts, a specification concerning design and installation was prepared for their technical approval. The approval of a first GFRP-post system confirmed that the requirements defined in the specification are reasonable and can be met. A coherent system of design values for strength and stiffness resulted from the process that differentiates between environmental impact (inside or outside the concrete foundation) and short- or long-term loading. The GFRP posts, composed of glass fibers and a polyester matrix with a protective coating, showed that even a small number of scratches in the coating may strongly affect the long-term strength of the GFRP material inside the concrete foundation. The post-foundation system stiffness decreased by only 7% during 12 million fatigue cycles due to concrete cracking and remained below the 10% limit prescribed in the specification.