Effects of vacuum heat-treated waste bamboo fibers on the drying shrinkage and mechanical properties of cementitious composites

Abstract

Vacuum heat-treated bamboo fibers (HFs) with different treatment temperatures (160–200 °C) and times (2–4 h) were used as fillers, and they were added to cement paste to fabricate cementitious composites with HFs (HFCs). The results showed that a high intensity of heat treatment could not only lead to the decomposition of hemicellulose and cellulose in the chemical composition but also to an increase in the mass loss of a bamboo fiber. Adding fibers treated at relatively high treatment temperatures (> 180 °C) for a long duration (> 2 h) significantly decreased the densities of HFCs. Additionally, the HFs improved the drying shrinkage of HFCs at a 75 % relative humidity in an early drying period. Furthermore, the tensile strength and compressive strength of HFCs with 2 h-treated fibers increased with increasing treatment temperature. However, the mechanical strengths of HFCs were not influenced by adding fibers treated for more than 2 h.

Keywords

• Vacuum heat treatment
• Waste bamboo fiber
• Cement
• Drying shrinkage
• Mechanical strength