Conceptual explanation to study the development of surface roughness Of frp composite piles during driving process

The surface roughness of FRP composite piles may be significantly altered during the driving process. This change could affect the interface pile design parameters. Therefore, an accurate quantification of this change is required to precisely determine the pile shaft resistance. This letter presents the results of an experimental study that investigated the change in surface roughness and interface shear coefficient of two different FRP counterface surfaces that sheared against two different types of sand under increased normal stress levels. The test results indicated that quantifiable surface roughness and interface resistance changes could be induced by the interface shearing process under increased normal stress levels. A conceptual explanation is provided in this study to interpret the observed behaviour. In conclusion, the outcomes of this study demonstrate the importance of considering the shear induced wear of FRP materials during the driving installation process.