木节对齿板连接剪切延性统计特性的影响  

The Effect of Knot on Statistical Characteristics of Shear Ductility of Truss-plate-connected Joints

作　　者：丁星[1] 张新培[1] 

机构地区：[1]四川大学建筑与环境学院

出　　处：《林产工业》2016年第12期21-25,共5页China Forest Products Industry

基　　金：成都市科技局惠民工程项目(2013惠民工程-12)

摘　　要：通过对比试验研究木节对90°纯剪、30°剪拉和150°剪压3类双剪试件齿板连接延性比的影响。试件选用北美二级SPF规格材及国产齿板制作,并设置有木节试件与无木节试件进行对比,有木节试件规格材连接区域含木节面积为482~2 016 mm^2。以有木节试件与对应的无木节试件延性比的比值为指标,通过正态性检验、方差齐性检验和方差分析研究木节对3类试件延性比比值的影响,并进一步分析延性比比值与木节面积的关系。结果表明:1)3类试件延性比比值的方差和均值无统计学上的显著差异;2)在试验选取的木节面积482~2 016 mm^2内,延性比比值的均值为0.993 4,变异系数为0.133 5,木节对延性比均值总体上影响很小,但延性比比值的离散性较大;3)在实际工程中,可以容许规格材连接区域内有一定面积或一定尺寸的木节存在。对于3类剪切试件,当规格材连接区域内木节面积小于2 016 mm^2(折算直径51 mm)时,可以忽略木节对延性比均值的影响。The effect of knot on ductility ratio of truss-plate-connected joints is investigated by compared experiments for three types of double shear specimens：90° pure-shear,30° shear-tension and 150° shearcompression.Specimens are made of second-grade SPF dimension lumber from North America and domestic truss plate,and two kinds of them are especially designed for comparing,the specimen with knot and its corresponding specimen without knot,the former containing knot areas ranging from 482 to 2 016 mm^2.Using the index,ductility ratio ratio（DRR）,definded as the ratio of ductility ratio of the specimen with knot to that of its corresponding specimen without knot,the influence of knot on DRR is studied by statistical methods of normality test,variance homogeneity test and variance analysis,and then relationship between DRR and knot areas is further analyzed.The results show that：1） the differences of mean value and variance of DRR are not statistically significant among the three types of specimens;2）in the range of knot areas of 482 -2016 mm^2,the mean value and variation coefficient of DRR are 0.993 4 and 0.133 5 respectively,which means that knot has little influence on mean value of DRR,but its discreteness is large;3） in practical engineering,knot in joint area of dimension lumber can be permitted for the three types of shear specimens and the effect of knot on mean value of ductility ratio can be neglected below knot area of 2 016 mm^2（convert diameter 51 mm）.

关 键 词：木节 齿板连接 延性比 均值 变异系数 统计分析 

分 类 号：TU366.2[建筑科学—结构工程]