Bamboo-precocious wood composite beams: bending capacity for long-term loading

Similar to timbers, bamboo shows creep behaviour under sustained load. However, a remarkable performance is shown during static experiments, the degradation of the performance by the creep must be discussed to secure the utilization over a long period. In order to study the longterm efficiency of bamboo laminas reinforcing low-quality precocious wood beams, a series of creep tests was carried out on two types of specimens: bamboo–poplar sandwich beams and non-reinforced poplar beams. Under a constant climatic condition, the load on the beams was stepwise increased to observe the behaviour at different load levels. Analyzing the experimental data of the sandwich beams, the long-term admissible load level, as well as the supplemental deformation was studied. In accordance with the Burger body model, their behaviour was analytically interpreted in order to obtain the coefficients characterizing the creep curves. Comparing these coefficients revealed the influence of bamboo reinforcement on the creep.