In high volume fly ash concrete, the higher of fly ash volume, the concrete strength and carbonization resistance. Expansion agent may ameliorate the strength of high volume fly ash concrete, and it has little influence on natural carbonization and could improve the resistance against compulsive carbonization. Development law of Long age period strength of high volume fly ash concrete indicates that its strength evaluation age shall be prolonged to 90 days. There is an optimum mixing proportion for auxiliary cementitious materials, where fly ash occupies 50% to 60% and expansion agent takes up6% . In this proportion, cementitious materials have favorable coordination between expansion and strength.%在大掺量粉煤灰混凝土中,粉煤灰掺量越大,混凝土强度和抗碳化性能下降幅度越大,而膨胀剂的加入对大掺量混凝土强度有改善作用,对自然碳化性能影响不大,但可提高抵抗强制碳化能力.大掺量粉煤灰混凝土后期强度的发展规律表明其强度验收龄期应延迟到90 d.得出一个最优辅助胶凝材料掺量组合,粉煤灰掺量为50％～60％,膨胀剂掺量为6％,在此条件下胶凝材料具有良好的膨胀与强度的协调性.
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