高地钩叶藤的主要物理力学性能研究

Study on the main physical and mechanical properties of Plectocomia himalayana

为构建健全的棕榈藤数据库、合理开发利用棕榈藤资源提供理论基础,以高地钩叶藤为研究对象,研究其主要物理力学性质及两种方式下的断裂韧性。结果表明,高地钩叶藤的气干密度、绝干密度和基本密度分别为0.44、0.46和0.36 g·cm^(-3)。体积气干干缩率和体积全干干缩率的变化范围分别为2.91%~8.11%和7.71%~11.36%,干缩各向异性较大。高地钩叶藤的抗弯弹性模量、抗弯强度、抗压强度、抗剪切强度和冲击韧性分别为804.10 MPa、49.95 MPa、33.12 MPa、4.77 MPa和184.02 kJ·m^(-2)。三点弯曲法测得其横纹断裂韧性为1 870 kN·m^(-3/2),紧凑拉伸法测得其顺纹断裂韧性为77.8 kN·m^(-3/2),说明高地钩叶藤的横纹断裂韧性比顺纹断裂韧性大得多。

In this paper, we chose Plectocomia himalayana Griff. as the experimental materials to study the main physical and mechanical properties and fracture toughness of two methods. The results showed that the air-dry density, absolute density and basic density of Plectocomia himalayana Griff. were 0.44, 0.46 and 0.36 g·cm^(-3), respectively. The volumetric air dry shrinkage rate ranged from 2.91% to 8.11%, the volumetric dry shrinkage rate ranged from 7.71% to 11.36%, and the dry shrinkage anisotropy was large. The flexural modulus,flexural strength, compressive strength, shear strength and impact toughness of Plectocomia himalayana Griff.were 804.10 MPa, 49.95 MPa, 33.12 MPa, 4.77 MPa and 184.02 kJ·m^(-2), respectively. The transverse grain fracture toughness measured by three-point bending method was 1 870 kN·m^(-3/2), and the fracture toughness parallel to the grain measured by the compact tensile method was 77.8 kN·m^(-3/2), which indicated that the fracture toughness of the transverse grain is much larger than that of the fracture along the grain.