Interfacial Performance in the Composite Strengthening of Existing Bridge Piers

The technology of the steel-concrete composite reinforcement method has developed rapidly in recent years. This method has emerged as one of the best choices for reinforcement， as it saves both time and space. At the same time， research on this method continues to progress. This study takes the third section of the north-to-east ramp of Chegongmiao Interchange in Shenzhen as the research object. A composite reinforcement scheme is proposed for the single-column pier of this curved bridge， with a focus on the interfacial performance between new and existing concrete after reinforcement， which has not been sufficiently investigated under this configuration. Nine sets of comparative experiments were conducted to analyze the key issue of shear resistance at the interface between new and existing concrete in the composite reinforcement scheme. It was found that under the circumferential reinforcement structure proposed in this paper， both ductility and failure bearing capacity were improved due to the Poisson effect in the later stage of the interface treatment component. At the same time， by applying the calculation formulas provided in existing reinforcement codes， the shear strength parameters for the new “serrated groove” configuration were introduced and evaluated.