Creep shear deformation of glued-laminated bamboo

Abstract

Glued-laminated bamboo has been applied to many parts of building structures. In peripheral, edge beams part of the multi-storey buildings and beams supporting canopy slabs, are not only subjected to bending moment but also to a shear load. Glued-laminated bamboo is classified as a viscoelastic material since it shows the properties which are common to both solid and fluid. In the long-term constant or steady loading, the glued-laminated bamboo will cause creep deformation. This paper discussed the experimental investigation of the creep behavior of glued-laminated bamboo subjected to pure shear. The specimens were apllied constant load with the different load level 20%, 30% 40% of the ultimate shear capacity. The instantaneous or elastic deformation was recorded after 1 minute a constant load was applied, then the load was maintained for 180 days. An intensive recording was done every 5 minutes for 60 minutes (1 hour), every 60 minutes (1 hour) until 300 minutes (5 hours), then every day until 90 days, every 1 month until 180 days. The results showed that creep shear deformation, strain and rate depend on load level. Creep shear deformation, strain and rate increased when the load level increased. The Burger and Power law model were used to fit the creep data and then can be used for predicting primary and secondary creep stage. The models were successfully for predicting viscoelastic creep shear parameters.