Influence of temperature on the adhesion of fibre reinforced polymers to timber surface

Abstract Carbon and glass fibre reinforced polymer composites are being increasingly used in timber structures, where they can be exposed to harsh temperature conditions. In order to be properly used, information is needed on their adhesion to the substrate. The objective of this research is to evaluate the influence of temperatures between 20 and 80 ºC on the adhesion of these reinforcements to the wood. The shear test of adhesive line and pull-off test of the reinforcement from wood surface were carried out using specimens made of Pinus spp. The results demonstrated that temperature causes the nonlinear reduction of the reinforcement adhesion. The specimens exposed to a temperature of 80 °C presented residual bond strength means of 34% and 20% of the mean strength at room temperature for CFRP and for GFRP, respectively. Caution in using the applied resins is required due to the presented behaviour even in the service temperature range specified by the manufacturers.

摘要 碳纤维增强聚合物复合材料（Carbon Fiber Reinforced Polymer, CFRP）与玻璃纤维增强聚合物复合材料（Glass Fiber Reinforced Polymer, GFRP）正日益广泛应用于木结构建筑，此类结构常处于严苛的温度环境中。为确保其合理应用，需明确此类增强材料与木材基底的黏结性能相关数据。本研究旨在评估20℃至80℃区间的温度对上述增强材料与木材黏结性能的影响。本研究以松属（Pinus spp.）木材制备试样，开展了胶层剪切试验与增强材料-木材界面拉拔试验。试验结果表明，温度会导致增强材料与木材的黏结性能呈非线性衰减。经80℃环境处理的试样，其碳纤维增强聚合物（CFRP）与玻璃纤维增强聚合物（GFRP）的残余黏结强度均值，分别仅为室温下强度均值的34%与20%。鉴于本次试验揭示的性能表现，即便在生产商规定的使用温度范围内，也需谨慎选用此类配套树脂胶黏剂。