| Bamboo is a kind of engineering structural material which is environment-friendly and hasexcellent mechanical performance. It possesses the properties of high strength, light weight, largerigidity and could improve natural environment during growth. Moreover the energy consumptionis low during processing, in addition, bamboo can be naturally degraded when discarded. Theplates and profiles with standardized sections and stable mechanical performance can be obtainedfrom raw bamboo experiencing a series of physical and chemical processing by means of modernindustrial technology, which can form modern bamboo structural buildings or bridges. Bamboobuildings have a great advantage in environmental conservation and earthquake-resistance.With features of material-saving, light weight and flexible forming method, cold-formedthin-walled section steel is available to larger gyration radius and inertia moment compared withordinary steel with identical cross-sectional area. Profile steel is prone to overall buckling and localbuckling with the increase of sectional width-to-thickness ratio. Thus buckling and instabilitybecome the main controlling factors in load-bearing capacity design. If it can effectively overcomeor ameliorate the defects, the utilizing efficiency and economy will be further improved, promptingits application field more extensive.In order to better play the mechanical performance advantages of bamboo and cold-formedthin-walled section steel, the present author has been devoted to the study of steel-bamboocomposite structures which are compounded of bamboo-based panels and cold-formed thin-wallsection steel by adhesive. Combination of steel and bamboo can avoid the problem that it’simpossible to develop different types of combination components made of pure bamboo such ashollow shape, I-shape and box-shape. Meanwhile, the capacity to resist buckling and instability ofthin-wall section steel will be enhanced effectively due to constraints of bamboo so as to achievethe complementary advantages of bamboo and steel.The paper mainly determines the basic mechanics index of recombinational bamboo,cold-formed thin-walled section steel basic mechanics index, shear performance indicators ofadhesive. Flexural tests of6composite beams are conducted simultaneously. The uniaxialconstitutive relation of recombinational bamboo is obtained through the axial tension andcompression tests. The flexural ultimate bearing capacity formula of recombinational bamboo isdeduced based on the constitutive relation with45specimens verifying its accuracy. Shear performance tests of25recombinational bamboo have been carried out at the same time. Flexural tests of6steel-bamboo composite beams are conducted by taking bamboo board thickness, steel plate thickness, sectional dimension and shear span ratio as parameters to observe failure characteristics and analyze the factors influencing composite beams. Theoretical expressions of slip, deformation and load-bearing capacity of steel-bamboo composite beams considering the interfacial slip effect are put forward. Furthermore, numerical simulation based on the slip effect is performed by application of ANSYS software.Studies have shown that the recombinational bamboo exhibits more complex mechanical relationships and its compressive ultimate strength can’t be fully developed in bending failure. Steel-bamboo composite beams indicate good composite effect, but the slip behavior affects the overall performance especially deformation capacity. In order to simplify the ultimate load-bearing capacity model of composite beams, we mainly take reinforcing effect of thin-walled cold-formed section steel to offset the decrease of ultimate load-bearing capacity of composite beams caused by its slip effect, making it possible to apply the computing model in practical work better. Placing COMBIN elements at the interface between the two materials can realize finite element numerical simulation for slip effect better and improve computational accuracy. |
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