Bearing mechanism of composite structure with reinforced concrete and steel liner: An application in penstock

For the composite structure comprised of steel-lined concrete, the inside steel liner and surrounding reinforced concrete are designed to work reliably. The potential sliding between the reinforced concrete and steel liner has a significant effect on the structure bearing mechanism. The Coulomb friction model is employed to simulate the sliding of the steel liner against the surrounding concrete. A concrete damage plasticity (CDP) model is proposed to simulate the surrounding reinforced concrete. The finite element (FE) models of the steel-lined reinforced concrete penstock (SLRCP) located on the downstream surface of a double curvature arch concrete dam are developed, in which the nodes-shared method (NSM) and the friction-contact method (FCM), respectively, are employed. The concrete crack initiation time, concrete crack propagation pattern, penstock deformation, tensile stresses of the steel liner and the reinforcements are presented. The results of the FCM model agree well with the monitoring data, validating that the proposed model could be directly employed in the FE software ABAQUS.