Performance test and mechanism analysis of moso bamboo chainsaw cutting

To explore the effects of process parameters on the cutting performance of moso bamboo during chainsaw cutting, and to establish a mechanism characterization method applicable to hollow round bamboo structures.

3-5-year-old moso bamboo was selected as the test material. A dedicated test bench for bamboo chainsaw cutting was constructed. Chainsaw specification, bamboo diameter, feed speed, and moisture content were selected as experimental factors, and peak cutting force and specific sawing energy were adopted as evaluation indices. Single-factor tests and L₉(3⁴) orthogonal array tests were conducted. In addition, the equivalent single-tooth average cutting thickness and normalized peak cutting force were introduced to carry out mechanism analysis.

The results showed that when moisture content increased from 40% to 80%, peak cutting force decreased from 48.14 to 34.29 N, and specific sawing energy decreased from 13.4 to 8.1 J/cm³. As bamboo diameter increased from 70 mm to 110 mm, peak cutting force increased from 31.18 to 52.40 N. When feed speed increased from 8 mm/s to 32 mm/s, peak cutting force increased from 26.44 to approximately 90 N, and specific sawing energy reached its relatively low value at around 24 mm/s. The orthogonal test results indicated that the factors affecting peak cutting force rank in descending order of influence magnitude as feed speed, chainsaw specification, moisture content and bamboo diameter. For specific sawing energy, the order of factor influence magnitude is chainsaw specification, feed speed, moisture content and bamboo diameter. Mechanism analysis revealed that when the equivalent single-tooth average cutting thickness increased from 0.07 mm to 0.41 mm, the peak cutting force increased from 18.66 to 101.51 N. The normalized peak cutting force exhibits a linear upward trend with the increase of equivalent single-tooth average cutting thickness, with a coefficient of determination R² of 0.702.

This study demonstrated that the peak cutting load of moso bamboo during chainsaw cutting is mainly controlled by single-tooth chip load. Moisture content, bamboo diameter, and chainsaw specification exert a modifying effect on cutting performance. The equivalent single-tooth average cutting thickness and normalized peak cutting force can be used to characterize the cutter tooth load and the stress intensity per unit effective cutting area in the chainsaw cutting of moso bamboo.