Study On Critical Force Of FRP Elongated Rod

Fiber-reinforced composites(FRP)are increasingly used in large spans,cable domes,and other important structures due to their lightweight,high-strength,corrosion-resistance,and other characteristics.FRP,as the main bearing component of the structure,has become stable in axial compression.The main factors affecting the safety of the entire structure.In this paper,based on the two-step pressure forming FRP slender rectangular rods,the stability of its axial compression was studied.First of all,the wood properties of the FRP members studied in this paper were tested,and their basic mechanical properties parameters were obtained.At the same time,the mechanical properties of FRP were theoretically deduced based on the relevant knowledge of FRP meso-mechanics to ensure the accuracy of the test results.Then,the XL3410 S multi-functional stabilizing tester was used to test the critical force of the rods of the FRP slender rectangular bar.During the test,by changing the boundary constraints at both ends of the rod,the critical force of the struts under different constraints was compared.The difference;change the length of the rod,compared the impact of different slenderness ratio on the critical force.At the same time,the pressure rod stability test is performed on FRP rods with the same length and different composition,and the main influencing factors of the critical force are compared;finally,the rod rod stability test is performed on the rods under the two forming methods of pultrusion and two-step pressure forming.,Compare the difference in the critical force of its pressure bar.The finite element analysis of FRP axial compression components was carried out by numerical simulation method.The finite element results were compared with the test results.The finite element analysis was performed on different diameter-thickness ratio pipes,and the different diameter-thickness ratio bars were observed.The law of critical force.Finally,the difference between the two Euler formulas and empirical formulas is compared.At the same time,the calculated results of each formula are compared with the actual values.The revised Euler formula can be used to predict the critical force of rectangular FRP members.Considering the initial bending of the FRP member,a modified Bailey's formula is proposed,which can be used to calculate the critical force of the compression rod considering the initial bending.