Resilient Precast Concrete Structures Using FRP Bolts and Tendons: Experimental Validation and a Resilience Performance Index

Abstract

Fiber-reinforced polymer (FRP) reinforcement is linear-elastic to rupture and is therefore brittle at the material level. However, this does not necessarily imply brittle response at the structural level when deformation, energy dissipation, and recovery are intentionally designed. Recent experimental and analytical evidence showed that precast concrete structures with FRP systems could achieve functional ductility and recoverability when ductile-by-design mechanisms were adopted, rather than relying on reinforcement yielding. For precast segmental beams prestressed with unbonded FRP tendons, functional ductility has been achieved through controlled joint opening/rocking, strain redistribution along unbonded tendons, and localized inelastic deformation and damage at interfaces. For precast beam–column joints assembled using FRP bolts and dry or hybrid interfaces, stable cyclic and impact responses have been reported when damage is shifted to intended interface mechanisms and confined to repairable regions, while the FRP fasteners remain elastic. To quantify the resilience of structures, a resilience performance index (RPI) is proposed based on the SDuMuRS concept (Sustainability, Durability, Multihazard resistance, Recovery, and Smart monitoring and management). The RPI is intended for structure-level application and implemented using conditional scoring when only partial pillar data are available from component-level studies. A worked example is provided for precast FRP-reinforced joints under impact loading, showing that fiber-reinforced concrete can improve conditional RPI values by simultaneously reducing peak deformation and enhancing recentering capacity. This paper proposes a mechanics-based and conditional resilience assessment framework for precast FRP systems, linking joint opening, tendon/bolt elasticity, residual deformation, recoverability, durability constraints, and smart monitoring into a unified RPI structure.