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In recent years, the zero-span tension technique of paper and pulp-making industry was applied to wood industry for indirectly testing the longitudinal tensile strength of tracheids. In this paper, this technique was used to test the longitudinal tension strength of tracheids for Chinese fir specimens with different widths. The results showed that average tension strength was 357.39 MPa. The order of average tension strength of tracheids was: 3 mm > 12 mm > 6 mm > 9 mm > 7.5 mm. But, earlywood samples frequently contained a little latewood and sample-making was difficult when the width of specimen was bigger, both the testing and the putting of samples were difficult when the width of specimen was smaller. Therefore, the width of 6 mm was chosen as the best width of specimen of Chinese fir.
In recent years, the zero-span tension technique of paper and pulp-making industry was applied to wood industry for indirectly testing the longitudinal tensile strength of tracheids. In this paper, this technique was used to test the longitudinal tension strength of tracheids for Chinese The results showed that average tension strength was 357.39 MPa. The order of average tension strength of tracheids was: 3 mm> 12 mm> 6 mm> 9 mm> 7.5 mm. But earlywood samples frequently contained a little latewood and sample-making was difficult when the width of specimen was bigger, both the testing and the putting of samples were difficult when the width of specimen was difficult. fir.