In order to improve the bending resistance of carbon fiber composite I-beams, the influence of different structural designs on the bending resistance of carbon fiber composite I-beams was studied. By using the experimental method of control variables and comparison, five experimental specimens of carbon fiber I beams with different structures are designed and three-point bending tests are carried out, and the experimental data such as bending strength and bending displacement of carbon fiber I beams are obtained; Secondly, the three-point bending model of carbon fiber I-beam is established with ABAQUS finite element software, and the validity of the model is verified. Then the model is used to analyze the stress of the I-beam in the three-point bending process, and the following conclusions are obtained:
(1) When the carbon fiber I-beam is in three-point bending, the stress of the upper flange is slightly greater than the lower flange. Properly increasing the thickness of the upper flange can improve the bending resistance of the I-beam, and increasing the thickness of the lower flange has little effect on the bending resistance of the I-beam;
(2) The stress value at the upper and lower ends of the web is always greater than the stress value at the middle of the web. Properly increasing the height of the web can improve the bending resistance of the I-beam, increase the thickness of the web, and have a weak impact on the bending resistance of the I-beam.
The above research has certain guiding significance for the structural optimization design of carbon fiber I-beam.
