CREEP RESPONSE OF GLULAM REINFORCED BY A NOVEL PRE-STRESSED FRP-WOOD COMPOSITE SYSTEM

摘要

Enhancement of strength and stiffness of glulam beams by the addition of fibre-reinforced plastic (FRP) sheets is nowadays a common practice. New developments have been ongoing to further improvement of the strength and stiffness of glulams. Recently a novel integral reinforcing system referred to as PWCL was patented [1]. This system is comprised of pre-stressed aramid, sandwiched and glued within layers of pre-compressed wood strands. The resulting sub-laminated system may be attached to the tension zone of glulam beams. As a result, the long-term performance of the composite beam that may be affected by the creep responses of the pre-stressed system must be established. This study outlines the details of a finite element model (FEM) constructed to predict the long-term behaviour of the entire reinforced glulam system, including the PWCL, under an externally applied load and constant environmental conditions. The FEM was developed in the Abaqus environment and the residual stress distribution was modeled in a step-wise scheme, corresponding to each step of PWCL and beam fabrication, as well as the in-situ response of the composite beam. The integrity of the creep model used in the simulation was verified by the experimental results obtained from tests performed on FRP reinforced glulam beams.