Abstract:
Bamboo is a high-quality material that is light, strong, and grows quickly. Bamboo structures have the advantages of environmental protection, ecology, low carbon and so on. It is a renewable and environmentally friendly biomass building material that is easy to obtain. However, full culm bamboo is often used to construct rural low-rise houses and temporary structures such as scaffolding or pavilions. This is because the irregular geometry of bamboo causes problems in building form and component connection, while the traditional bamboo architecture has poor performance in fireproofing, heat insulation, sound insulation and so on. Bamboo is difficult to use in buildings to meet the requirements of comfort. In order to fully exploit the natural advantages of bamboo and overcome its deficiencies, a new type of multifunctional composite members which combines bamboo skeleton and composite material was presented. The composite material was mainly composed of a combination of mortar, polystyrene particles, and mineral adhesives. It is wrapped on the surface of the bamboo skeleton. Through the full-scale tests of multifunctional composite members, the process of force transfer, bearing capacity, failure mode and enhancement function of composite material were observed. The results showed that composite material provided a good binding effect and greatly improved the axial compressive bearing capacity of the composite members. However, there was still a gap between the above-mentioned ultimate bearing capacity and the strength failure result. The failure mode of the composite members was cracking of composite material on the side elevation. Because of slippage between composite material and bamboo studs, the restraint effect of the composite material on the studs was weakened, and the ultimate failure of the composite members was caused by instability. Analysis of finite element parameters showed that when the number of studs is less than 6, the axial bearing capacity of each composite members stud increased with the increase of the number of studs. Conversely, the axial bearing capacity of each composite members stud was reduced. When the spacing of the composite members studs were in the range of 200-500 mm, the average bearing capacity of the stud increased with the increase of spacing. When the composite members was loaded uniformly, the composite members was in a state of global buckling failure, but when the middle single composite members stud was loaded, the top of the stud appeared the phenomenon of local crushing. The failure mode of the bamboo skeleton sprayed with composite material was bending failure at joining of concentrated load, accompanied by slippage between bamboo and composite material, and the pressure was borne by composite material before 30 kN, with the increase of load, the pressure was borne by the top of bamboo. When the allowable deflection and peak deflection of the composite member are achieved, the bearing capacity of the composite member is about 7 and 4 times as much as that of the bamboo skeleton member, the composite material can greatly increase stiffness of the bamboo skeleton member, the proteiform disadvantage of bamboo subjected to bending can be overcome . The multifunctional bamboo skeleton member sprayed composite material has good performance, the results provided a reasonable basis for the theory and engineering application of composite member.