Reliable interface connections of composite decks are important for their structural performance. To promote engineering applications of GFRP-concrete bridge decks, both the distributed sand bonding interface and the wet epoxy resin bonding interface are considered in the present study. Previous GRFP-concrete interface details are also optimized based on the double-shear test results of the GFRP-concrete composite bridge deck. Ten specimens are manufactured and tested under static loading, and the test results are compared with the previous test results. The present study shows that, with the optimized GFRP-concrete interface, the deformation of the specimens agrees with the plane deformation assumption during the loading process. The specimens show good integrity and high load-carrying capacity as well as good capability in recovering their deformations. Although brittle failure modes are observed in the specimens, large deflections occur before failure, which give some failure warning and ensure relatively high reservation of strength safety.