复合加固方形中长木柱轴压性能研究OA北大核心

In order to study the axial compression mechanical properties and improve the theory of square medium-long timber columns strengthened with near surface mounted steel bars and wrapped carbon fiber reinforced polymer(CFRP)strips,the axial compression performance of composite strengthened timber columns was studied through experimental research,theoretical analysis and numerical simulation in this paper.In the experimental study,axial compression tests were carried out on eight timber columns with different strengthening forms,using the number of embedded steel bars,the amount and wrapped ways of CFRP strips as parameter variables.The failure characteristics,load-displacement curves,and load-strain curves of specimens were analyzed,and the test results were compared with those of the composite strengthened square short timber columns.Experimental results show that the load bearing capacity of the composite strengthened square medium-long timber columns increases by 14.12％to 67.05％compared with un-strengthened timber columns.Meanwhile,a finite element numerical analysis model was established using ABAQUS software.On the basis of the varified model,the influences of the slenderness ratio of specimens,the reinforcement ratio of the section,and the spacing width of CFRP strips on the reinforcement effect were studied.The analysis reveals that the load bearing capacity of the composite strengthened timber columns gradually decreases with the increase of the slenderness ratio and significantly decreases when the slenderness ratio is greater than 70.When the reinforcement ratio is around 2.5％and the width of the CFRP strips and the spacing are both 150 mm,the mechanical performance of composite strengthened square medium-long timber columns is the best.