Increasing the flexural capacity of geopolymer concrete beams using partial deflection hardening cement-based layers: A numerical study

Experimental research has demonstrated the great flexural performance of deflection hardening cement-based composites for strengthening the beams. this paper numerically investigates the feasibility of adding thin deflection hardening fiber-reinforced layers to the bottom of geopolymer concrete beams to enhance the flexural performance. to properly predict the structural behavior and crack patterns of beams, the smeared crack approach was adopted to simulate the beams. the numerical simulations were executed in the fem-based computer program. to validate the developed numerical models, the experimental test beams were numerically simulated with a cross section of two layers. regarding the results obtained, the models would well predict the structural behavior and crack patterns of beams. to ensure the efficiency and accuracy of the adopted constitutive model in predicting the structural behavior and crack patterns of beams, the numerical fe models were used to simulate the added hardening deflection fiber-reinforced layer to the bottom of geopolymer concrete beams. the numerical results revealed that adding a thin fiber-reinforced layer to geopolymer concrete beams resulted in increasing ultimate load capacity, ultimate deflection, and ductility. the greatest enhancement in the flexural performance of the strengthened beams was found in the ultimate load capacity of the strengthened beams.