Experimental Study on Mechanical Properties of Bamboo Culms and Joints Reinforced with GFRP Sheets

Abstract

Bamboo is a kind of a green renewable traditional building material with the advantages of high tensile strength parallel to grain and fast growth, which can meet the development needs of green and ecological fabricated buildings. However, the round bamboos are likely to crack under pressure, especially at the bottom of the column and bolted bamboo joint, because of stress concentration. To solve the above problems, glass fiber reinforced polymer (GFRP) was used to strengthen the natural bolted bamboo joints in this study. Then shear tests and pressure tests were carried out in order to find an effective way to improve the compression resistance capability of the bamboo column and shear behavior of bolted bamboo joint. The bearing capacity and failure modes were observed and studied. Compared with the specimens without reinforcement, the maximum deformation capacity of the GFRP reinforced bamboo column specimens is increased by at least 2.5 times, and the bearing capacity is increased by 5.5%–11.7%; the maximum deformation capacity of the GFRP reinforced bamboo joint specimens is increased by at least 2.5 times, and the bearing capacity is increased by 3–6 times. Therefore, GFRP is a kind of material which can greatly improve the deformation and bearing capacity of bamboo column or bolted bamboo joint. In addition, GFRP can prevent brittle failure and improve ductility of specimens.Although the bearing capacity of GFRP reinforced bamboo joints has been greatly improved compared with that without reinforcement and the stress has also been greatly enhanced, the maximum load that the bamboo joint can bear is still far lower than that of the bamboo column due to the lack of bearing area. How to make full use of the bearing capacity of bamboo in addition to the node is the key point to be solved in the future, one suggestion is to add fillers to bamboo joints.