Review of moment redistribution in statically indeterminate RC members

Moment redistribution is a specific behaviour in statically indeterminate reinforced concrete (RC) structures due to the structural redundancy and nonlinear characteristics of the reinforced concrete. Considering moment redistribution in practical design is an effective way to fully exploit the reserve capacity of the materials and to provide convenience for construction. However, the evolution of moment redistribution is a complex process and has been the subject of numerous studies dating from the middle of the last century. This paper presents a review to summarize and discuss the reported experimental and numerical studies of moment redistribution with the aim of reaching a clearer understanding on the development regulation of this behaviour and making a more accurate determination of moment redistribution in practical design, thus improving the construction phase of building structures. The members highlighted in this review include conventional steel reinforced concrete members, fibre-reinforced polymer (FRP) reinforced concrete members, fibre reinforced concrete members, and retrofitted concrete members. Important influential factors discussed in this paper are longitudinal reinforcement ratios, longitudinal reinforcement arrangement, concrete strength, yield strength of tensile reinforcement, slenderness of members, concrete confinement, and the new features of special materials. A comparison of results in the literature with the current code provisions is also presented. It is found that these code provisions tend to be conservative as the effects of many important parameters on moment redistribution are neglected. Therefore, further studies are suggested to provide a more realistic and cost-effective design guideline for utilizing moment redistribution in practical engineering to achieve economical design and construction.