EXPERIMENTAL RESEARCH ON A NON-WELDING Y-SHAPED STRENGTHENING TECHNIQUE OF POWER TRANSMISSION TOWERS

The bearing capacity of the existing power transmission tower which has been in operation for a long time is reduced, and there is a risk of collapse in strong wind. In the paper, a Y-shaped strengthening technical scheme which can be applied to the existing transmission tower members was presented. The scheme does not need welding and is convenient for construction. Axial compression tests on one unstrengthened specimen and two strengthened specimens adopting this scheme were carried out. The results showed that the axial load bearing capacity of the specimen adopting Y-shaped strengthening scheme was significantly improved. The bearing capacity of the two strengthened specimens was 1.25 and 1.53 times higher than that of the unstrengthened one, respectively. It indicated that the Y-shaped strengthening scheme could effectively improve the bearing capacity of the original section. The friction between the original and auxiliary materials generated by the clamps could gradually transmit the axial force of the original section to the strengthened section, making the original materials and the strengthening components resist the load together. In the later loading stage, the force transmission efficiency of each cross section tended to be stable, and after a certain distance from the loading end, the force transmission efficiency could reach 40% to 60%.