Research on the creep property of the recombinant bamboo based on the theory of variable-order fractional derivative and the stress level effect
摘要
For the natural fiber-reinforced composite materials, such as the recombinant bamboo obvious creep behavior is usually observed. In this paper, the compressive creep property of the material was chosen as the research subject. First the standard compressive fracture experiment was carried out to provide the basic stress level parameters for the compressive creep test. Then the creep experiment under four different stress levels was conducted to record the strain evolution process. Finally the creep property was analyzed based on different selected models and the stress level effect. The results showed that the stress level affects the creep property obviously. The creep strain growth speed under higher stress levels is much quicker than that under lower stress levels. In addition, compared with the traditional Burgers model, the combination of the variable-order fractional derivative defined Maxwell model and the stress level defined model parameters can provide excellent performance in fitting the strain evolution process during the whole experiment period, which makes it worth popularizing and utilizing in actual engineering.