| Original state arc reorganization of bamboo is the a new efficient utilization way in the field of bamboo processing which bionics is used, which keeps the natural bamboo arc structure, improve the utilization rate of bamboo, that it is widely used in new high strength structural material manufacturing. At present, there are some progressed of research on technology and equipment of Arc Bamboo Recombining in Original Status(A-BROS), however, the research of adhesive strength of A-BROS and its key processing equipment have not been described. The research contents were as follows. The preparation technology of arc bamboo were studied, physical and mechanical performance of arc bamboo were analysed using the software ANSYS, surface wettability and roughness of arc bamboo were studied, arc bamboo finish milling machine was developed, the relation between preparation technology and bonding strength were discovered, micromorphology and stress strain contribution of conglutination interface were revealed, therelation of agglutination performance and micro properties were established, which could realize the optimization of design of original state arc reorganization of bamboo. It also has important practical significance and theoretical value for preparation of arc bamboo and design of original state arc reorganization of bamboo.The main research work and corresponding results of this paper are summarized as follows.(1) It proposed the preparation technology of arc bamboo, carried out the finite element and mathematical modeling analysis, the results show: processing technic of arc bamboo is bamboo-truncation-grouping according to the diameter of bamboo-broken bamboo-rough milling(removing the outer of bamboo and inner of bamboo) dry-finish milling(arc bamboo); The bending capacity of arc recombinant section is better than rectangular recombinant section. The stress angle and deflection of bamboo arc sectional beam are smaller than bamboo rectangular sectional beam, which verified by theoretical calculation.(2) Developed arc bamboo finish milling machine, arc bamboo’s processing thickness can reach 6~9mm, processing width can reach 25~45mm, the minimum processing length is 600 mm. The equipment runs smoothly, bamboo processing width can reach 42 mm, meet the production requirements of gluing.(3) Researched the surface wettability of arc restructuring unit by contact angle tester, the results show that: the wettability of distilled water, UF and P-MDI on the outer of bamboo in FMAB and RMAB is better than the inner of bamboo, the wettability of FMAB is better than RMAB, the wettability of distilled water on the RMAB is great, the wettability of UF and P-MDI have no obvious difference; The effects of arc bamboo type, bamboo surface and adhesive on the contact angle is extremely significant, significant level in the initial contact angle and equilibrium contact angle reach 0.0001, the interaction between factors can influence on the contact angle.(4) Researed surface roughness of arc restructuring unit by the surface roughness measuring instrument. The results show that: the outer of bamboo of FMAB surface roughness, and respectively for 4.29μm, 23.7μm and 32.3μm,the inner of bamboo surface roughness, and respectively for 6.22μm, 33.0μm and 46.9μm,significantly less than RMAB roughness.(5) Researched bond performance test on water content, arc bamboo type and rubber, explored the relationship between technology and bonding strength. The results show that: the bonding performance of FMAB is better than RMAB, bonding performance in vertical and parallel directions almost equal, P-MDI bonding performance is better than UF, bonding performance in arc bamboo moisture content is 8~11% better, with the increase of water content, bonding performance decline; the bonding strength of A-BROS is 1.12 MPa which made by FMAB and P-MDI, the thickness swelling rate is 1.31%, can be used as structural materials.(6) Researched the microstructure of the arc restructuring unit broken bonding interface by ESEM, analysed the influence of different factors on the bonding performance of arc restructuring unit. The results show that: P-MDI permeability on the outer of bamboo and inner of bamboo is better than UF; With the increase of arc bamboo unit water content, the permeability of P-MDI gradually decrease, the mechanical properties of bonding interface also decrease; The high surface quality of FMAB is conducive to the infiltration of adhesive; the outer of bamboo and the inner of bamboo of A-BROS have high precision surface, Bond performanceis better, and close to the bond performance between them.(7) It tested the strain distribution in A-BROS under different loading conditions by digital speckle correlation method, and researched the stress strain and displacement curve of interface fracture. The results show that: the strain distribution variation of A-BROS change great which suppressed different roughness and adhesive. When parallel and vertical loading on outer of bamboo, the loading time before breaking of FMAB and P-MDI bonding interface is longer than RMAB and UF bonding interface, it is similar with fault displacement, but slope between the displacement and time are almost the same. The maximum load and deflection which FMAB and P-MDI can bear is greater than RMAB and UF, this shows that FMAB, P-MDI has better performance. |
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