Moment redistribution in glass fiber reinforced polymer-reinforced concrete continuous beams subjected to unsymmetrical loading

This paper investigates the behavior of glass fiber reinforced polymer (GFRP)-reinforced concrete (RC) continuous beams subjected to unsymmetrical loading conditions. A total of six large-scale RC continuous beams were constructed and tested to failure. Three different loading cases were considered, (I) loading both spans equally, (II) loading both spans maintaining a load ratio of 1.5 and (III) loading one span only. The effects of reinforcing material type, assumed percentage of moment redistribution and serviceability requirements on the performance of the test beams were investigated. Also, a comparison between the experimental deflection and that predicted by available models, using effective moment of inertia approach, is presented. Test results revealed that, beams tested under unsymmetrical loading case II showed less crack widths, strains and deflections in the higher load span compared to those in the less load span or those symmetrically loaded. Moreover, the unsymmetrical loading conditions adversely affected the moment redistribution.