摘要
选择胶合竹为研究对象,以双组分环氧树脂为胶黏剂,采用拉—拉荷载模式开展胶合植筋连接抗拔性能研究。主要探讨了边距、胶层厚度以及长径比等对植筋连接抗拔强度的影响。结果表明:边距对植筋连接抗拔强度有一定影响,边距过小导致胶合竹开裂,抗拔强度下降,推荐边距应大于4d(植筋杆直径);胶层厚度对植筋抗拔强度影响不显著;长径比是影响植筋连接抗拔强度的重要因子,抗拔强度随长径比的增大而增大,并存在一个临界植入深度使得抗拔强度等于植筋杆屈服强度。胶合竹与胶黏剂粘接界面名义剪切强度随长径比的增大而减小。根据长径比给出植筋抗拔强度预测方程。试验过程中主要产生胶合竹开裂、植筋杆拔出和植筋杆屈服3种破坏模式。
With structural glued laminated bamboo as study object,we used two-component epoxy to study the pull-out strength of glued in rod,and tested the specimens in pull-pull configuration. We also studied the influence of edge distances,glue thickness and the slenderness ratio on pull-out strength. The edge distances had certain effect on pull-out strength,the pull-out strength was decreased when the edge distance was too small; because the glulam was cracking in this case,the recommended edge distances was 4d（ d is the rod diameter）. The glue thickness had insignificant effect on pull-out strength. The slenderness ratio has an important effect on pull-out strength. The pull-out strength was increased with the slenderness ratio increasing,and there was a critical embedded depth making the pull-out strength of glued-in rod equal to the yield strength of the steel rod. The nominal shear strength of glulam / adhesive was decreased with slenderness ratio increasing. We got the mean pull-out strength of a single axially loaded rod set parallel to the grain. The main failure modes were glulam cracking,shear failure along the rod and yielding of the rod.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2015年第4期96-100,107,共6页
Journal of Northeast Forestry University
基金
林业公益性行业科研专项(201204701)
关键词
胶合竹
边距
胶层厚度
长径比
抗拔强度
Structural glued laminated bamboo
Edge distances
Glue thickness
Slenderness ratio
Pull-out strength
