C15C20C25C30C35C40C45C50fck1013.416.720.123.426.829.632.4ftk1.271.541.782.012.22.392.512.64fck混凝土轴心抗压强度标准值ftk混凝土轴心抗拉强度标准值N/mm2C15C20C25C30C35C40C45C50fc7.29.611.914.316.719.121.123.1ft0.911.11.271.431.571.711.81.89fc混凝土轴心抗压强度设计值ft混凝土轴心抗拉强度设计值强度种类混凝土强度等级强度等级混凝土强度等级C55C60C65C70C75C8035.338.541.544.547.450.22.742.852.932.993.053.11C55C60C65C70C75C8025.327.529.731.833.835.91.962.042.092.142.182.22混凝土强度等级混凝土强度等级