Mechanical behavior of glubam engineered bamboo at low temperature

Glubam is a type of engineered bamboo, which can be used as structural members in buildings. To explore the potentials of glubam for various application environment, this study examines the bending performance of three types of glubams at conditions of low temperature (-196 degrees C-20 degrees C) and freeze-thaw cycle. A total of 260 specimens were tested under static bending at different temperatures, in order to provide the reference data for the low-temperature design of the bamboo structure. The elastic modulus (MOE) and modulus of rupture (MOR) of three types of glubams under the condition of oven-dried and air-dried were measured respectively through static bending tests. The morphological characteristics after low-temperature treatment were explored by optical microscope and scanning electron microscopy (SEM). The results showed that thin-strip glubam, thick-strip glubam and side-pressed glubam all show good bending performance at -50 degrees C. The oven-dried glubam showed a different variation trend from air-dried glubam and the strength variation amplitude of oven-dried glubam is smaller than that of air-dried glubam. Glubam at conditions of low temperature and freeze-thaw cycle showed the same variation trend. However, the effects of freeze-thaw cycle on MOR and MOE were not significant. This pilot research provides basic performance data for potential applications of engineered bamboo in low temperature situations, such as buildings and facilities in polar regions as well as extremely low temperature situations such as high altitude.