[Objective]This research aims to investigate the bearing performance of domestic dimension lumber joints connected with domestic truss plate,and to offer a reference for the development and utilization of domestic building materials.[Method]Larix kaempferi dimension lumber harvested from Dagujia Forest Farm of Qingyuan Country,Liaoning Province,and domestic truss plates were selected as the experimental materials. The lateral resistance of teeth in four conditions was tested,with five repeated specimens for each condition. The shear strength in ten conditions was tested, with three specimens for each condition. The bearing capacity of L. kaempferi joints connected by truss plates under different working conditions were investigated and compared with imported truss plates and imported SPF dimension lumbers.[Result]The result shows that lateral resistances of teeth under conditions of AA,AE,EA,EE are 3. 50, 2. 53,2. 61 and 2. 37 N·mm -2 ,respectively. The strength of imported M20 truss plate is slightly lower than that of domestic truss plate under the EA working condition. While show 10. 57%,21. 34%,9. 28% higher,respectively,under circumstances of AA,AE,EE by comparing the result of the two samples,which are L. kaempferi joints connected by domestic truss plates and those by import truss plates. On the other hand,the lateral resistances of teeth tested with import M20 truss plates connected by L. kaempferi are 36. 27%,50. 49%,30. 00% and 40. 00% higher than those by SPF under the four working conditions of AA,AE,EA,EE,respectively. The shear strengths of plate are 132. 39,122. 73, 135. 66 ,199. 13 ,92. 26 ,172. 76 ,99. 81 ,89. 52 ,79. 10 and 85. 68 N·mm -1 respectively under working conditions ofθ=0°,θ=90°,θ=30° T,θ=60° T,θ=120° T,θ=150° T,θ=30° C,θ=60° C,θ=120° C as well asθ=150° C. The strengths of domestic truss plates connected with L. kaempferi are higher than those of imported truss plates connected with SPF except one when tested under θ=120° with shearing and tension.[Conclusion]The failure modes are identical for lateral resistance of teeth under four conditions,which was pulling out of the teeth. For shear strength test,the failure modes are splitting of dimension members at the abutting area,pulling out of teeth at the end of truss plate and warping of truss plate. Loading direction has significant impact on the bearing capacity of the truss plate joints. Compared with the imported truss plate connected SPF joints with,the load carrying performance of domestic truss plate connected Larix kaempferi joints with is better. Further research on L. kaempferi wood trusses connected with domestic truss plates may provide a scientific basis for development of Chinese wood structure system.%[目的]研究国产规格材与国产齿板连接节点的拉伸及抗剪承载性能,为国产建筑材料的开发利用提供参考.[方法]以采自辽宁清原大孤家林场的日本落叶松规格材及市购国产齿板为试验材料,设计制作4种工况下的板齿极限强度试件及10种工况下的齿板抗剪强度试件,通过拉伸和剪切试验,研究不同工况下日本落叶松齿板连接节点的板齿极限强度和齿板抗剪强度,并与进口齿板和进口SPF规格材进行对比.[结果]日本落叶松与国产齿板连接节点的板齿极限强度在AA、AE、EA和EE 4种工况下分别为3.50、2.53、2.61和2.37 N·mm-2,通过比较日本落叶松与国产齿板、进口齿板2组结果,除EA工况下进口M20齿板强度略低外,在AA、AE和EE 3种工况下分别高于国产齿板10.57%、21.34%和9.28%,对比进口M20齿板与日本落叶松、进口SPF 2组结果,在AA、AE、EA和EE 4种工况下与日本落叶松的组合分别高于与进口SPF的组合36.27%、50.49%、30.00%及40.00%;齿板抗剪强度在 θ=0°、θ=90°、θ=30°T、θ=60°T、θ=120°T、θ=150°T、θ=30°C、θ=60°C、θ=120°C和 θ=150°C 10种工况下分别为132.39、122.73、135.66、199.13、92.26、172.76、99.81、89.52、79.10和85.68 N·mm-1,除剪-拉复合受力情况下 θ=120°时国产齿板和日本落叶松组合的齿板受剪极限强度较小外,其他工况均大于进口齿板与进口SPF的节点组合.[结论]板齿极限强度试验在4种工况下的破坏方式均为齿拔出破坏,齿板抗剪强度试验主要破坏方式为木材接缝处开裂、齿板端部齿拔出和齿板在木材接缝处翘曲等;荷载方向对齿板连接节点承载力影响较大;国产齿板和国产日本落叶松的齿板连接性能较好,且优于常见进口齿板和进口SPF的节点组合,可进一步研究国产齿板和国产日本落叶松制成轻型木桁架的承载性能,为完善我国木结构建筑体系提供科学依据.
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