Study on the Mechanical and Creep Properties of the Bamboo Fiber Under Thermal or Hygro Conditions

The aim of the study is to investigate the mechanical and creep properties of the bamboo fiber under thermal or hygro conditions. Bamboo fibers were extracted mechanically, and then undergone alkali treatment. The bamboo fiber in this study is actually thin bamboo sticks instead of the real bamboo fibers. This bamboo stick will retain the structure of the original. Tensile tests of the bamboo fiber were. The yield and the tensile strength were found to decrease with the increase of the moisture content or temperature. Creep tests of the bamboo fibers were conducted to investigate the viscoelastic behavior. Results show that the strain creep curve can be divided into three stages. In primary creep phase, strain increases at a decreasing rate. The secondary phase exhibits a linear response with time, also called steady-state creep. The tertiary stage is the stage in which strain response almost increases exponentially, resulting in the failure of the fiber. In the creep test, the applied force was maintained 25 N, and the fracture strain was about 0.7%-0.8%. A mathematical constitutive model was constructed to fit the creep curves. The creep fitting curve only includes the primary and secondary phases, and the fitted curve can roughly show the creep behavior of the bamboo fiber.