ADAPTABILITY OF BURGERS RHEOLOGICAL MODEL AND ITS IMPROVED MODEL TO THE CREEP PROPERTIES OF GLUE LAMINATED BAMBOO

The proportion of bamboo material used in industrial production has increased year by year. The glue laminated bamboo (GLB) is a kind of bamboo engineering material. GLB can be used in modern buildings, bridges, furniture and other fields. It is necessary to study its mechanical properties, especially its creep properties. In the paper, the short-term creep performance of GLB is studied at four stress levels. At first, the Burgers rheological model (BRM) and the improved Burgers rheological model (IBRM) are used to study the creep properties of GLB. The parameters of the two models are obtained by fitting the experimental data. The results show that BRM is only suitable for the elastic deformation part of the GLB material. But the nonlinear viscosity coefficient is introduced into IBRM, so it can better describe the creep characteristics of GLB. On this basis, IBRM and BRM are used to predict the long-term creep performance of GLB based on the obtained creep parameters. The results show that the prediction error of BRM is large, and the prediction result of IBRM is in good agreement with the experimental data. It shows that IBRM is more suitable to describe the creep characteristics of GLB.