Dynamic characterization of timber beams reinforced with GFRP

摘要

A study on the static and dynamic properties of timber sawn beams reinforced with glass fiber-reinforced polymer (GFRP) is reported in this paper. The experimental program is focused on the behavior of unidirectional wooden slabs. The main objective is to fulfill the service state limit upon vibrations using GFRP reinforcements when an architectonical retrofitting project is necessary. Different timber (pine tree wood) beams were analyzed and reinforcements made with GFRP were also applied. Two different typologies of reinforcement were checked: one only applied the GFRP on the lower side of the beams while the other also covered half of the lateral sides. For the dynamic characterization the natural frequencies, damping ratio, and dynamic elastic modulus were measured through two different techniques: experimental modal analysis upon the whole beams; and bandwidth method using smaller samples of the same material.