各标号混凝土强度合格所需回弹值混凝土标号合格所需回弹值平均炭化深度（mm）0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6C15 22.9 23.2 23.4 23.6 23.9 24.1 24.4 24.6 24.9 25.1 25.4 25.7 25.9C20 26.6 26.9 27.1 27.4 27.7 28.0 28.1 28.5 28.9 29.1 29.5 29.7 30.1C25 29.8 30.1 30.4 30.7 31.1 31.4 31.7 32.0 32.3 32.7 33.0 33.4 33.7C30 32.8 33.1 33.4 33.8 34.1 34.5 34.8 35.2 35.5 35.9 36.3 36.7 37.1C35 35.5 35.8 36.2 36.6 37.0 37.3 37.7 38.1 38.5 38.9 39.3 39.7 40.1C40 38.0 38.4 38.8 39.2 39.6 40.0 40.4 40.8 41.3 41.7 42.1 42.5 43.0C45 40.4 40.8 41.2 41.6 42.1 42.5 42.9 43.4 43.8 44.3 44.7 45.2 45.7
