| As a green,environment-friendly,and renewable unidirectional fiber reinforced composite material,bamboo scrimber has a wide application prospect in building structural engineering because of its even and exquisite texture,excellent mechanical property,strong processibility,and other qualities.At present,the two materials of bamboo/wood-concrete composite structures are mostly connected through shear connectors,and there are few studies on the use of adhesives.In this paper,supported by“the Fundamental Research Funds for the Central Universities”（2021ZY53）,the bonding interface of reconstituted bamboo-concrete was studied through a single-sided shear test,in order to explore the effects of different bond lengths,widths and thicknesses of bamboo scrimber,concrete strengths,and adhesive layer thicknesses on the shear performances of bond interfaces.The main research contents are as follows:（1）In this thesis,44 bamboo scrimber-concrete single shear samples are designed by orthogonal test method.Plus,a self-designed fixing device is used to carry out the tests.The failure behavior and debonding load-carrying capacity of bamboo scrimber-concrete interfaces are also comprehensively analyzed according to the shear test phenomenon.From the experimental results,it is obvious that the failure behavior of the interfaces are almost the same under different influencing factors.Besides,the debonding load-carrying capacity of the specimens can be effectively improved through increasing the widths and thicknesses of bamboo scrimber,the strengths of concrete,and the thicknesses of adhesive layers.（2）Based on the data collected by the strain gauges,the interfacial shear stress and the relative slip of bamboo scrimber-concrete interface are calculated by strain distribution difference method.To explore the load-slip relationship between reconstituted bamboo and concrete.The distribution rule of stress and strain at the interface is studied,and the debonding failure process of the bamboo scrimber-concrete specimen is studied by observing the stress transfer process zone,and the influence of different influencing factors on the peak stress of the interface is also analyzed.（3）According to the bond-slip curve of the bamboo scrimber-concrete interface,three bond-slip constitutive models are constructed.Through the regression analysis of the test data,not only are the characteristic parameters of the model curve revised,but also the calculation formula of the peak stressτmax under different factors is given.By comparing with the experimental data,it is found that the Popovics model can truly show the variation of shear stress with the relative slip of the interface in the bamboo scrimber-concrete interface.（4）Based on the fracture mechanics research method,not only is a bond strength model of bamboo scrimber-concrete interface proposed,and the formulas for calculating interface fracture energy and effective bond length are established.Besides,the validity of the bond strength model is also verified through comparative analysis.Based upon the study on the shear performance of bamboo scrimber-concrete bond interface,the conclusions of this thesis will not only supply the calculation basis and method criterion for the design of bamboo scrimber-concrete composite structures,but also have important reference value for the permanent formwork and decorative panel engineering of bamboo scrimber. |
