| Bamboo/wood preservation is an important issue of current wood industrial development. In this paper, for the wind blade spar with bamboo and wood composite materials in cold thermal curing of the rheological model and the start of this paper to the poplar, bamboo stripes and rheological behavior of compression were carried out research and evaluation, but also on the Poplar veneer Laminated wood, bamboo and wood composite LVL suppression techniques, the amount of resin impregnation, the optimal pressure, etc. were studied. The results are as follows:(1) Viscoelastic Behavior of poplar under radical compressionA study on the different thickness of Poplar (Populus nigra) veneer. The effects of the different strain levels,temperature,moisture content and the adhesive on stress relaxation of poplar veneer were explored. The results showed that: 25±2 degree,under the same deformation, The amount of Stress relaxation in proportional to Moisture Content ;0% Moisture Content, As the temperature increases, The amount of Stress relaxation increase slightly;0% moisture content,under the same deformation,Poplar veneer with adhesive have a greater amount of Stress relaxation,And the Stress relaxation of poplar veneer behavior can be used by the Maxwell model and spring model composed of three components to simulate.(2) Creep behavior of bamboo under radical compressionDiscussed the bamboo (Phyllostachs edulis) under a constant pressure with different temperatures,different moisture content relationship, Identified the corresponding creep model, also studied bamboo with node compression creep performance. The results showed that: Under the compressive stress less than the yield limits, Burger model can be used to simulate bamboo radial compression of the short-term creep behavior; The four–element model parameters were as the temperature and the Moisture content decreased. Bamboo node creep results showed that the bamboo with node permanent creep deformation increases.(3) The analysis for Poplar LVL Dimensional stability,Resin impregnation and RheologyUse different way prepare Poplar LVL. Mainly analyzes the factors that impact LVL dimensional stability,and analysis the factors that impact stress relaxation and dimensional stability. The results show that pressure and temperature on Poplar LVL dimensional stability of the most significant.And strengthened laminated veneer lumber (LVL). was manufactured using Poplar(Populus nigra) veneer as raw materials, Poplar veneer were impregnated in epoxy resins with different solid contents, and then to calculate the amounts of resin impregnation with different time durations; The effects of the impregnation amount on LVL stress relaxation,2hTS and longitudinal compressive strength were also explored. The results showed that :(1) When the solid contents of the epoxy resin were the same, the impregnation increment of the Poplar veneer increased with the impregnation time and then became stable;(2) When the impregnation time durations were the same, the impregnation increments of the Poplar veneer impregnated in epoxy resin with higher solid contents were higher than those in epoxy resin with lower solid contents;(3) AS the impregnation increment increased, The density of Poplar LVL and longitudinal compressive strength increased and then stabilized, 2hTS decreased and then stabilized.(4) Within the scope of the experiment, Poplar veneer were impregnated in epoxy resins with solid content of 55%>5h,LVL can reach better requirement. (4)The optimal pressure of Bamboo/wood composite under Cold compression and Thermal curingStrengthened laminated veneer lumber (LVL) was manufactured using Poplar (Populus nigra) veneer and bamboo as raw materials, Explored the impact of different pressures on the LVL,When the Assembly patterns is 4, 5 Bamboo Wood,The density of LVL,2h TS,longitudinal compressive strength on properties of the bamboo/wood composite LVL were explored, Under the experimental conditions , The Optimal pressure range is 3~5MPa.
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