黄连根茎物理力学特性试验性究

Experimental Study on Physical and Mechanical Properties of Rhizomes of Coptis Chinensis

通过实地探访和试验获得了黄连形态结构特征参数,测定黄连根系约90%的质量分布在入土深度为0~60 mm的土壤中.应用万能拉伸试验机对收获期黄连根茎进行了拉伸和剪切特性试验研究,分析了黄连根茎拉伸和剪切断裂方式,以及根茎含水率和直径对其力学特性的影响,结果表明,黄连根茎的极限拉力随着根径的增大呈现出增大的趋势,黄连根茎的极限伸长率随着根径的增大呈现出减小的趋势,但含水率范围不同,变化幅度不同;当根茎含水率在80%~130%和130%~180%时,黄连根茎的极限剪切力随着根径的增大而大幅增大,当含水率在180%~230%时,黄连根茎的极限剪切力随着根径的增大而平缓减小.研究结果可为黄连机械化收获关键部件的拉拔与采挖过程提供基础设计参数.

The morphological and structural parameters of Coptis chinensis were obtained through field investigations and tests.It was determined that about 90%of the root system of Coptis chinensis distributed in the 0~60 mm depth of soil.The tensile and shear properties of rhizomes of Coptis chinensis during harvest period were tested with universal tensile tester,and the tensile and shear fracture modes of rhizomes of Coptis chinensis were analyzed,as well as the influence of water content and diameter of rhizomes on their mechanical properties.The results showed that the ultimate tensile force of rhizomes of Coptis chinensis increased with the increase of root diameter,while the ultimate elongation of rhizomes of Coptis chinensis decreased with the increase of root diameter,but the range of water content was different and variation of the range is different.When the water contents of rhizome were between 80%~130%and 130%~180%,the ultimate shear force of rhizome of Coptis chinensis increased greatly with the increase of root diameter.When the water content was between 180%~230%,the ultimate shear force of rhizome of Coptis chinensis decreased smoothly with the increase of root diameter.The research results can provide basic parameters fordesigning the key components of pulling and excavation process in mechanized harvesting of Coptis chinensis.