FRP增强胶合木梁的受弯性能研究

对FRP(fiber reinforced plastics/polymer)增强胶合木梁的受弯性能做了详细研究。通过试验分析了构件的破坏形态与破坏机理,对比分析了FRP增强胶合木梁与未增强梁的极限荷载与抗弯刚度等受弯性能。试验结果表明FRP增强杨木胶合木梁相对于未增强梁,受弯极限承载力提高了18%~63%,刚度提高了32%~88%,当配筋率为1.0%左右时,FRP增强杨木胶合木梁的受弯承载力与刚度分别可达到常用松木实木构件的1.82倍和1.35倍,并且增强构件的破坏形式大多表现为塑性受压破坏。基于力学模型分析,提出了粘结界面粘结剪应力、截面中性轴位置、FRP板拉力、受拉面层破坏荷载和极限荷载等的计算公式;然后将理论分析结果与现有的大量试验结果进行了对比,结果表明,模型精度较高,能够较好地预测FRP增强胶合木梁的受弯性能,可为此类结构构件的加工设计与工程应用提供参考。

Study on flexural behavior of FRP reinforced glulam beams

A detail study on flexural behavior of FRP(fiber reinforced plastics/polymer) reinforced glued laminated timber(glulam) beams is presented in this paper.Through the experimental work,the failure modes and failure mechanism were discussed,then the ultimate load and the flexural stiffness of FRP reinforced glulam beams were compared with those of unreinforced control beams.It is shown that reinforced poplar glulam beams with FRP increased the ultimate load by 18%～63%,and bending stiffness by 32%～88%.And when compared with the sawn pine beams,the ultimate load and the stiffness of the reinforced poplar glulam beams with reinforcement ratio of 1.0% were 1.82 and 1.35 times higher,respectively.Furthermore,the failure modes of the reinforced beams showed ductile compression failures.Based on the analysis of mechanic model,it developed the equations for computing the interfacial bonding shear stress,position of neutral axis,tensile force in FRP strips,the load at bumper-lam failure and the ultimate load.Compared with a large number of test data,the presented model shows a satisfied accuracy and it can be used to predict the flexural behavior of FRP reinforced glulam beams.And the whole work can be taken as a reference for manufacture,design and application of this kind of structural members.