普通混凝土与高强混凝土抗压强度的尺寸效应

通过对27组边长为100，150，200mm，强度等级为C20，C40和C60的普通混凝土和高强混凝土立方体试件进行抗压试验，系统研究了不同强度等级普通混凝土和高强混凝土试件立方体抗压强度的尺寸效应，建立了强度等级与立方体抗压强度尺寸效应的关系，得到了普通混凝土和高强混凝土抗压强度尺寸效应的临界尺寸和临界强度，提出了立方体抗压强度尺寸效应律的计算公式，并通过试验数据验证了该公式的适用性.试验结果表明：普通混凝土与高强混凝土的立方体抗压强度均具有较明显的尺寸效应现象，强度等级越高，尺寸效应越明显，C20混凝土立方体抗压强度尺寸效应度约为C60混凝土的55%.

Scale Effect on Cubic Compressive Strength of OrdinaryConcrete and High Strength Concrete

Scale effect of compressive strength of ordinary concrete and high strength concrete were investigated through compression experiments on ordinary concrete and high strength concrete specimens with the strength grade of C20, C40 and C60, and the specimen side length of 100, 150, 200mm. The relationship between the strength grade and scale effect was established. Then, the critical size and critical strength of ordinary concrete and high strength concrete were obtained. Furthermore, the computational equations of scale effect were proposed. Finally, good agreements have been found between tested data and the computational equations. The test and analysis results show that the scale effect exists in the cubic compressive strength of the ordinary concrete and high strength concrete. With an increase in the strength grade, the scale effect is significantly enhanced. The scale effect of concrete with strength grade C20 is 55% of the concrete with strength grade C60.