A comparative analysis on methodologies for determining the saturation fiber point in bamboo

The stability of dimensional and load-bearing capacity of bamboo, as a green and sustainable engineering material, is critically important during its processing and utilization. Properly managing moisture content through fiber saturation point (FSP) had a significant impact on both bamboo production and its engineering applications. Therefore, the accurate determination of the FSP of bamboo was crucial for practical applications and the effective moisture content control. This study performed a comprehensive analysis on the determination of FSP in bamboo using three methods: LF NMR, mechanical and shrinkage testing. The findings indicated that the FSPs were 23.2 % and 22.3 % as determined by the mechanical method and low-field NMR method, respectively. The shrinkage method produced FSP values of 26.7 %, 26.6 %, and 28.6 % in the longitudinal, tangential and radial directions, respectively. While the three methods yielded comparable experimental outcomes, each demonstrated distinct advantages and limitations in FSP determination. The findings addressed the discrepancies in determining FSPs for bamboo using the three methods and provided essential guidance for the industrial processing and engineering application of bamboo.