C40R60 High volume fly ash (HVFA) concrete were adopted for the continuously casting massive foundation slab of Tianjin Tower, which has a volume of about 20 000 m3, to decrease the risk of cracking during the construction process. Suitable raw materials and mix proportion were chosen. The properties of hardened concrete cured under different conditions were investigated. A mock-up of massive structure with the dimension of 4.5×4.5×4m was cast using determined concrete. The temperature development in the core of structure was measured. The results show that the temperature rise in the core is relatively low and the compressive strength curing under the standard condition for 60 days is 54.3MPa. HVFA concrete is much suitable to the massive concrete structure in which elevated temperature would be kept for a long time.