Comparative tests of the wall thickness effect of a glass-reinforced thermosetting plastic coating with a non-circular cross section in a soil-coating object for economic aspect

Culvert structures made of plastics are employed extensively in the construction of new facilities as well as the renovation of existing ones. Due to the high costs of materials required for the manufacturing of these goods, the objective of this research is focused to lessen the thickness of the walls, which may, on the other hand, result in a reduction in the stiffness of the system. In the course of the testing, the structure was subjected to both vertical and horizontal displacements, and wall deformations were measured in both the central portion of the section and at the junction. The results of the tests were assessed to determine whether or not the reduction in wall thickness had an effect on the amount of deformation that occurred in the structure's internal cross-section as well as the wall stresses. GRP pipes with reduced (optimized) wall thickness can withstand comparable loads to the ones with thicker walls, which opens up consideration about possible application of such products for sustainable development of circular economy.