木结构螺栓连接横纹受力性能试验研究  

Experimental study on mechanical behaviors of timber structures loaded perpendicular to grain by bolted connections

作　　者：冯新[1,2] 肖宏彬[2] 陈伯望[2] 晏班夫[3] FENG Xin;XIAO Hongbin;CHEN Bowang;YAN Banfu(Hunan Engineering Laboratory for Manufacturing and Application Technology of Modern Timber Structural Engineering Materials,Central South University of Forestry and Technology,Changsha 410004,China;College of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,China;College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]中南林业科技大学现代木结构工程材制造及应用技术湖南省工程实验室,湖南长沙410004 [2]中南林业科技大学土木工程学院,湖南长沙410004 [3]湖南大学土木工程学院,湖南长沙410082

出　　处：《建筑结构学报》2021年第2期151-165,共15页Journal of Building Structures

基　　金：国家自然科学基金项目(51578554);国家住建部科技项目(2018-K9-069);湖南省教育厅科研项目(15C1419);中南林业科技大学青年基金项目(QJ2013001A)。

摘　　要：木结构螺栓连接横纹受力在现代木结构应用中难以避免,其横纹劈裂承载力计算目前尚缺乏相关规范作指导。设计制作了185根锯材木梁和54根胶合木梁螺栓连接横纹受力试件,进行了横纹劈裂承载力试验研究。结果表明:劈裂承载力与梁截面宽度成正比,与连接节点相对加载高度呈非线性关系,而与螺栓直径无关,螺栓布置方式对劈裂承载力无明显影响;简支梁试件劈裂承载力与连接节点沿跨径所在位置无关,但对于外伸端螺栓连接的外伸梁试件,其横纹劈裂承载力相对于简支梁试件出现了无明显规律的降低现象;当梁的有效跨高比l/he≥5时,梁的跨径对其劈裂承载力没有影响。对比国外相关木结构规范和计算模型,提出了计算木结构螺栓连接横纹劈裂承载力的修正模型,其预测值与锯材试件试验结果之比的平均值为0.92,与胶合木试件试验结果之比的平均值为0.94,验证了所修正模型的精确度和适用性。In modern timber structures,it is inevitable to use bolted connections which lead to significant stresses perpendicular to grain.However,the splitting capacity calculation of the members loaded perpendicular to grain by bolted connections in the structural design remains unspecified in the national standards of China.A total of 185 sawn lumber and 54 glulam beams were designed and manufactured to be tested under loading perpendicular to grain by bolted connections to obtain their experimental splitting capacities.The test results indicate that the splitting capacity is in proportion to the beam width,has a nonlinear relationship with the relative connection height,and is independent of the bolt diameter.No significant effect of the bolt arrangement on the splitting capacity is observed.The results also show that for the simply supported beams,the splitting capacity is independent of the position of the connection along the beam span,while for the beams with a bolt-connected cantilever part,the splitting capacity of the cantilever part is found to be reduced compared with the simply supported beams.The splitting capacity is also found independent of the span when the effective span-depth ratio is not smaller than 5(l/h_e≥5).Based on the relevant timber structure standards and theoretical calculation models abroad,a modified model to predict the splitting capacity of timber structures loaded perpendicular to grain by bolted connections was proposed.The average ratio of predicted splitting capacity to mean experimental splitting capacity is 0.92 for the sawn lumber beams,and is 0.94 for glulam beams.The accuracy and the feasibility of the proposed model are validated by test results.

关 键 词：木结构 螺栓连接 横纹受力 试验研究 劈裂承载力 破坏模式 

分 类 号：TU366.2[建筑科学—结构工程]