| Due to frequent earthquakes in recent years, people have raised their requirements for building security, which necessitates the research on strengthening joints in the reinforced concrete frame. Despite many experimental studies, both domestically and abroad, have been done in the stress and anti-seismic performance of frame joints after strengthening, the number of researches on the effectiveness of different strengthening methods is still limited.This thesis first introduces stress mechanics and two frequently used strengthening methods of frame joints, namely sticky-steel strengthening method and sticky-CFRP strengthening method. Additionally, in the background of joints of a company’s office building, comparisons are made between the anti-seismic performances of these two methods by MIDAS/FEA, a finite element software. And the result is then verified by checking the shear capacity of joints. It shows that both strengthening methods can improve the effectiveness of reinforcement and the shear capacity, but the sticky-steel strengthening method outperforms the sticky-CFRP strengthening method.This thesis focus on examines how key factors affect the effectiveness of reinforcement, including axial compression ratios, the strength grade of concrete, the thickness of steel plate, and layers and models of CFRP. It shows that there is a threshold under which the axial compression ratios and the effectiveness of reinforcement are positively related, while above it, they are negatively related. Moreover, it suggests that C35-C45 should be the optimum range of concrete grade for economic consideration. And the reinforcement performs best with 2mm-6mm steel plate and 2 or 3 layer CFRP. When choosing strengthening methods and strengthening materials, also should undertake the economic consideration.In conclusion, this thesis could to provide constructive reference for strengthening projects of frame joints. |
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