Precast Geopolymer Concrete Sandwich Wall Panels Enabled by FRP Shear Connectors

Prefabricated concrete sandwich panels (PCSP), consisting of two concrete wythes and a thermal insulation layer in between, have great potential in use for industrialized building construction. This presentation is concerned with a research project on the development of a new precast sandwich concrete wall system, for which the two exterior wythes are made of geopolymer concrete while the composite action is realized through the use of fiber-reinforced polymer (FRP) shear connectors. The work reported here includes three aspects: (1) evaluation and optimization of the performance of FRP shear connectors; (2) tests on the stiffness and strength performance of FRP/steel reinforced geopolymer concrete slabs; and (3) composite action of geopolymer sandwich wall panels. Both experimental and analytical results demonstrated the efficiency of FRP tubular shear connectors, which have been newly developed in the presenter’s research group. The FRP/steel reinforced geopolymer concrete slabs were found to exhibit similar structural performance with their Portland cement concrete counterparts. As a consequent, the PCSP system developed based on the FRP tubular shear connectors and the reinforced geopolymer concrete wythes could exhibit satisfactory composite action in terms of both the strength and the stiffness. Due to its low carbon and durable feature in addition to its thermal and structural efficiency, the developed PCSP system is expected to have wider applications in prefabricated building industry which is now very popular in Hong Kong as well as the rest of China.