坡向对毛竹主要物理力学性质的影响

Impact of Different Slopes on Main Physical and Mechanical Properties of Bamboo

研究不同坡向毛竹主要物理力学性质的变化,为竹材资源合理开发、加工和利用提供理论依据。按照GB/T 15780—1995对毛竹材的气干密度、基本密度、抗弯弹性模量、顺纹抗压强度、抗弯强度进行了测定,结果表明:气干密度、基本密度随毛竹轴向高度增加呈增加趋势,其中,东北、西南坡向的基本密度分别为0.699 g.cm-3和0.720 g.cm-3,气干密度分别为0.798 g.cm-3和0.835 g.cm-3,西南坡向毛竹的基本密度、气干密度分别增加了2.973%和4.618%,在0.05水平上经T-检验差异显著。东北坡向与西南坡向毛竹的抗弯弹性模量、顺纹抗压强度、抗弯强度分别为12 368.281、1 244.71 MPa,55.8585、6.206 MPa和183.203、179.918 MPa,其中,东北坡毛竹的平均弹性模量较西南坡高9.08%。

According to the China national strandard GB/T 15780-1995, the air-dry density, basic density, MOE, compressive strength parallel to grain and MOR of bamboo were measured. The results showed that both the air-dry density and basic density increased along with the increase of axial height. The basic density and air-dry density of bamboo on northeast-facing and southwest-facing slopes were 0. 699 g ·cm^-3 and 0. 798 g ·cm^-3 , 0. 720 g ·cm^-3 and 0. 835 g ·cm^-3 respectively. The basic density and air-dry density of southwest- facing slope increased by 2. 973% and 4. 618% compared to the values on northeast-facing slope respectively. They were significantly different at 0.05 level in T-test. The MOE, the compressive strength parallel to grain and the MOR of bamboo on northeast-facing and southwest-facing slope were 12368.28 MPa ＆ 11244. 71 MPa, 55. 858 MPa ＆ 56. 206 MPa and 183. 203 MPa ＆ 179. 918 MPa respectively. Among them, the MOE on northeast-facing slope bamboo increase by 9. 084%, and the differences of MOE between northeast-facing and southwest-facing slopes were remarkable at 0.05 level in T-test.