截面尺寸、加载方式和指接形式对落叶松大尺寸结构指接材抗弯性能的影响  

Effects of Cross Section,Loading Mode and Finger-Joint Type on the Bending Property of Larch Structural Finger-Jointed Lumber in Large Dimension

作　　者：周志芳[1,2] 毕克新[1] 张雪松 毛磊[1] 赵思淼 王齐[1,2] 李晨琦[1] 

机构地区：[1]黑龙江省木材科学研究所,哈尔滨150081 [2]黑龙江省木材综合利用重点试验室,哈尔滨150081

出　　处：《林业科学》2016年第3期82-89,共8页Scientia Silvae Sinicae

基　　金：国家林业公益性行业科研专项"工程木质复合材料结构承载性能检测技术研究"(201304514)

摘　　要：【目的】研究截面尺寸、加载方式和指接形式等因素对落叶松大尺寸结构指接材抗弯性能的影响,得出不同试验因素下的抗弯强度特征值,为结构指接材的分级技术提供测试数据和可行性建议,为大尺寸结构指接材的抗弯强度测试标准及其特征值的确定方法提供参考,推动落叶松及其他树种作为结构指接材在建筑结构上的应用。【方法】参照LY/T 2228—2013《轻型木结构-结构用指接规格材》标准,选取2种尺寸(截面尺寸为40 mm×90 mm和40 mm×140 mm)的Ⅱc等级落叶松材料加工成结构指接材,采用数理统计方法检验样本数据的正态性和方差齐性,然后用2个独立样本t检验方法判定试验因素对大尺寸结构指接材抗弯强度和抗弯弹性模量是否有显著影响。【结果】截面尺寸、加载方式和指接形式在特定条件下对抗弯强度和抗弯弹性模量有显著影响。截面尺寸对V形指接侧面抗弯强度和侧面抗弯弹性模量均有显著影响,即截面尺寸大的(40 mm×140 mm)侧面抗弯强度和侧面抗弯弹性模量也大;不同加载方式对抗弯强度没有显著影响,但对截面为40 mm×140 mm试样的抗弯弹性模量有显著影响,即侧面加载方式测得的抗弯弹性模量明显高于平面加载方式;不同指接形式对截面为40 mm×140 mm的试样平面抗弯强度有显著影响,即V形指接的平面抗弯强度高于H形指接的平面抗弯强度,而指接形式对截面为40 mm×90 mm的试样侧面抗弯强度和抗弯弹性模量均有显著影响,即H形指接的侧面抗弯强度和抗弯弹性模量高于V形指接的侧面抗弯强度和抗弯弹性模量。在大尺寸结构指接材抗弯性能检测数据的基础上得到了参数法和非参数法计算的强度特征值,参数法计算的特征值低于非参数法。【结论】落叶松结构指接材完全可用作木质工程材料,宽面承载、V形指接以及适宜的截面尺寸有利于保证结构指接材的�【Objective】The effects of cross section,loading mode and finger-joint type on the bending property of larch structural finger-jointed lumber in large dimension was studied.Then the characteristic values under the different experimental factors（ cross section,loading mode and the finger-jointed type） were obtained.These are very important to the domestic researches of the bending property of larch structural finger-jointed lumber in large dimension.【Method 】According to LY/T 2228—2013,larch（ Larix gmelinii） timbers of grade Ⅱc with two different cross section（40 mm×90 mm and 40 mm×140 mm） were chosen to fabricate the structural finger-jointed lumber.The statistical methods were used to do normality test and homogeneity of variance test, and two-sample t test was applied to check whetherexperimental factors（ cross section,the loading mode and the finger-jointed type） significantly influencing the modulus of rupture（MOR） and modulus of elasticity（ MOR） of larch structural finger-jointed lumber in large dimension.【Result】The experimental factors（cross section,the loading mode and the finger-jointed type） had significant effect on the MOR and MOE in some particular situations.The cross section had significant effect on both MOR and MOE of the samples with V finger-jointed type and narrow side loading mode.Concretely,this effect was that MOR and MOE of the samples with large cross section（40 mm×140 mm） were higher than those of the samples with small cross section（40 mm×90 mm）.The difference in loading mode did not behave significant effect on the MOR.But the loading mode obviously influenced the MOE of the samples with large cross section（40 mm×140 mm） behaving that the values of MOE tested in the narrow side loading mode were higher than those of the large side loading mode.The finger-jointed type also significantly influenced MOR of samples with large cross section（40 mm×140 mm） and large side loading mode.In details,the MOR of the samples with V fing

关 键 词：结构指接材 抗弯性能 大尺寸 特征值 

分 类 号：S781.2[农业科学—木材科学与技术]