Reduction of Thermal Stress Induced in a Steel Plate Strengthened by Bonded Aluminum-CFRP Composite:

In steel members strengthened with carbon-fiber reinforced polymer (CFRP) plate, thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched. Therefore, the thermal stress caused by temperature change has to be considered when designing the repair or strengthening of a steel member with CFRP plates. With this in mind, the authors proposed a technique to reduce thermal stress in steel members strengthened by CFRP plate on both side, which involves bonding aluminum alloy plates with CFRP plates. In this proposed method, the thermal stresses in steel member can be reduced so that there are negligible levels of stress when the cross sectional areas of CFRP and aluminum plates are designed to correspond the coefficient of thermal expansion of steel, even though the thermal stresses are introduced in the CFRP and aluminum plates. So far, a thermal bending moment was not c...