| China is the forest resources deficient country, and regardless of the forest acreage or the amount per capita is lower than the world's average, and domestic high quality and large diameter timber resources are especially scarcer. But plantation lumber, small diameter timber and sawmill slab resources are abundant. Moreover, our country is rich in bamboo resources, and the acreage and the output come first in the world. The comprehensive utilization of those rich resources is important to alleviate our country timber resources contradictory between supply and demand, and promote the sustainable development of wood-based board industry.Bamboo has merits such as higher strength, bigger hardness, better toughness, and abrasion-resistant, also has shortcomings like small diameter and low utilization. In addition, plantation lumber and small diameter timber have merits like easily machined and higher manufacturing efficiency, but simultaneously have shortcomings such as lower strength, lower hardness of surface, and bigger residual stress. Therefore, bamboo/wood composite materials could strengthen the fine property of bamboo and wood scientifically and rationally, obtain the purpose of reducing the cost of production and guaranteeing the intrinsic and exterior quality.Wood combing processing, using small diameter timber and sawmill slab to produce the new constitution unit, was a unique method. China fir strip obtained from combing processing was simple root. Except less in macroscopic size, China fir strip almost did not change microscopic organizational structure, and maintained physical and mechanical properties of raw material by the greatest extent. Divided China fir strip into four grade using the method of manual screening. The result showed that the mass percentage of grading A was 20.0%; the mass percentage of grading B was 35.3%; the mass percentage of grading C was 20.4%, and the mass percentage of grading D was 23.4%.Bamboo/wood composite orient strand lumber was manufactured, using China fir strip combed from small diameter timber and sawmill slab and waste bamboo strip obtained from the process of slicing bamboo square as raw materials. Under the laboratory condition, the effects of the hybrid ratio of bamboo and wood,the resin consumption of China fir strip, the proportional relations between thick China fir strip and thin China fir strip, and the board density on properties of bamboo/wood composite orient strand lumber were explored. The orthogonal testing method was carried on the experimental design to obtain the optimum manufacturing technology of bamboo/wood composite orient strand lumber. The results showed that: (1) the physical and mechanical properties of bamboo/wood composite orient strand lumber had enhanced along with the increasing of the content of waste bamboo strip; (2) the hybrid ratio of bamboo and wood, the proportional relations between thick China fir strip and thin China fir strip, as well as the board density all had significant influences on modulus of rupture and modulus of elasticity. And the resin consumption of China fir strip was found to have a major effect on thickness swelling of water absorbing and internal bonding strength; (3) the optimized parameters were obtained as hybrid ratio of bamboo and wood 2:8, resin consumption of China fir strip 9% (10%), thick China fir strip and thin China fir strip mixed evenly, and board density 0.75g·cm-3. According to the optimized parameters obtained from laboratory test, bamboo/wood composite orient strand squared lumber was carried on pilot testing, and its physical and mechanical properties were examined. The results showed that: (1) the manufacturing technology of bamboo/wood composite orient strand squared lumber was feasible; (2) the strength of bamboo/wood composite orient strand squared lumber was closely related to density and hybrid. The products had even quality and excellent physical and mechanical properties, so they could be widely used. |
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