Nonpenetrating repeated impact effect to the damage behavior of prestressed glass/epoxy composite pipes

Abstract

AbstractGlass‐reinforced plastic (GRP) composite pipes, the use of which has been increasing rapidly in many areas in recent years, may be exposed to the impact of different objects during assembly, operation, repair, and maintenance. Since composite materials are sensitive to impacts, it is vital to examine damage to the material. In this study, the repeated impact response of GRP composite pipes under internal hydrostatic pressure was investigated. In order to simulate different operating conditions on the GRP samples, a prestress was created by applying 4, 16, and 32 bar internal hydrostatic pressure. Then, the prestressed pipes were subjected to low velocity repeated impact tests. As a result of repeated impact tests at low velocity, changes in maximum displacement amount, maximum contact force, energy absorption capacity, and impact velocity were evaluated depending on the number of impacts applied to the samples. The changes in the strength of the samples subjected to repeated impact tests at different internal pressure levels were determined by the hoop tensile tests performed according to the ASTM D2290 standard. As a result of the hoop tensile tests, the variation of the material's tangential tensile strength and damage behavior according to impacts' number and the prestress were investigated.