A.< 0.5B.0.50~0.55C.0.55~0.60D.0.60~0.65
A.2.3~2.8B.1.8~2.2C.2.85~3.20D.3.3~3.7
A.试验系数B.水泥标号C.混凝土试验强度D.灰水比