Abstract：Geopolymer is a new type of chemically activited cementitious material which has been actively investigated across the world for more than 10 years. It may become a green cementitious material to replace cement. In view of the relatively weak durability of alkali activated fly ash (AAFA) geopolymer，recent research progress in AAFA geopolymer based concrete worldwide is systematically reviewed in terms of carbonation resistance，freeze-thaw resistance，chloride ion penetration resistance，acid and sulfate resistance，and weathering resistance. Literature survey results can be summarized as follows：1) Compared with ordinary Portland concrete (OPC)，the anti-carbonization ability of AAFA concrete is weaker，so the carbonized AAFA concrete has an increased porosity and decreased mechanical properties. High temperature curing and addition of Ca(OH)2，OPC cement，ground granulated blast furnace slag (BFS) and nano-TiO2 can improve the carbonation resistance of the AAFA concrete. 2) The freeze-thaw resistance of AAFA concrete is generally low. Adding BFS and metakaolin can improve the freeze-thaw resistance of AAFA concrete. 3) Compared with OPC，AAFA concrete has higher Cl- permeability，and the addition of BFS，lower liquid-solid ratio，high temperature curing，and prolonging curing time can improve the Cl permeability performance of AAFA concrete. 4) AAFA concrete has strong resistance to sulfuric acid，hydrochloric acid，nitric acid，acetic acid and sulfate，and has low water absorption. 5) The efflorescence resistance of AAFA is relatively weak. This is closely related to porosity. Extending the heat curing time，adding aluminum-rich additives，lowering the target sodium to aluminum molar ratio，reducing the water content of the geopolymer，adding nano-SiO2 and silane surface modification can improve the efflorescence resistance of the AAFA concrete.
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