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Experimental study on impact of aggregate mixture on dimensional effect of concrete cubic compressive strength

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Abstract

In order to investigate the dimensional effect of concrete cubic compressive strength, a series of compression tests were performed on 135 groups of cubic specimens with three different strength grades and three different aggregate mixtures. The strength grades of specimens included C20, C40 and C60, and the side lengths of specimen included 100 mm, 150 mm and 200 mm respectively. Test and analysis results show that the strength grade influences the dimensional effect of concrete cubic compressive strength greatly. The value of dimensional effect degree of 200 mm cubic specimens with strength grade C40 and C60 are about 1.61 times and 1.85 times of cubic specimens with strength grade C20. The dimensional effect is influenced greatly by the coarse aggregate. The dimensional effect degree of concrete is about 2.7 times of the mortar. The fine aggregate affects the dimensional effect much weaker than coarse aggregate. The dimensional effect degree of cement is about 88 percent of the mortar. Furthermore, the computational dimensional effect law equation on the concrete was proposed based on the test results. The predicted results of the proposed equation agreed well with test data.

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