结构设计竞赛中的受拉竹条力学性能实验及选用方法

Mechanical Properties and Selection of Tension Bamboo Strips Used in Structure Design Contest

受拉竹条是全国大学生结构设计竞赛中的常用杆件,但目前对受拉竹条科学选用方法的研究较为欠缺。因此,针对太原理工大学结构设计竞赛中常用的1 mm×6 mm、2 mm×2 mm和3 mm×3 mm这3种不同截面竹条开展受拉力学性能实验研究,探究含水率、质量、维管束数量和刨磨处理等因素对抗拉极限承载力的影响。研究结果表明:竹材强度随含水率增加先增大后减小,最佳含水率为14%;对未处理的杆件,抗拉极限承载力与杆件质量存在线性关系;杆件质量相近时,可通过维管束数量和竹条颜色选择受拉竹条;通过刨磨处理杆件稀疏维管束,可减轻质量,提高荷质比;研究结果可为结构设计竞赛中受拉竹条科学选用提供参考依据。

Tension bamboo strips are common structural elements in the National Structure Design Contest for College Students.At present,however,the research is scarce on the scientific selection of tension bamboo strips.Therefore,mechanical experiments were performed to study the tensile properties of bamboo strips with cross-sections of 1 mm×6 mm,2 mm×2 mm and 3 mm×3 mm commonly used in structure design contest.And the impacts of moisture content,weight,number of vascular bundles and planing treatment on the ultimate tension capacity were examined.The results indicated that the tensile strength of bamboo strips increased first and then decreased as the moisture content rose,and the optimal moisture content was 14%.For untreated bamboo strips,there was a linear relationship between the ultimate tension capacity and the weight;When the weights were similar,the tension bamboo strips could be selected by the number of vascular bundles and the color of bamboo.If part of bamboo strip with sparse vascular bundles was removed by planning and grinding,the weight was reduced and the load-to-mass ratio was improved.These results may serve as references for selecting tension bamboo strips in structure design contest.