Bending behavior of glass fiber reinforced composite overwrapping pvc plastic pipes

Abstract

The challenge associated with the use of polyvinyl chloride (PVC) plastic pipelines is to improve their structural integrity without increasing their cost. Currently, PVC pipelines are the most cost-effective method of transporting water and sewage drainage. However, their low deterioration and mechanical properties cause significant losses and sacrifice the structural integrity of pipelines. Therefore, this study proposes the glass fiber-reinforced polymer (GFRP) overwrapped system to strengthen the external surface of PVC pipes, which will improve pipes’ flexural load-carrying capacities. Accordingly, an extensive experimental program is developed and performed to examine the flexural behavior of GFRP composite overwrapped onto PVC plastic pipes. These phases include the fabrication process and different types of tests for evaluating the structural integrity of the GFRP/PVC pipes. The results showed that the proposed overwrapped system significantly improved the flexural carrying capability. The initial flexural failure load increased significantly, with an improvement from 64 to 1140 N. Also, the ultimate flexural load found to be improved by a factor of nine. The flexural behavior was significantly affected by changes in the fiber orientation angle. The results also revealed that as the pipe diameter increased, the flexural carrying load capacity increased. It is also important to note that the matrix cracking, fiber debonding, and fiber breakage were dominating the failure modes of GFRP/PVC pipes.