Possibility of Testing the Compressive Strength of Concrete on the Halves of Prisms Specimens

Abstract

Compressive strength, as the main mechanical property of the building materials, depends on geometrical characteristics of the tested specimens: cube, cylinder or prism. Unlike concrete strength tests, where different specimens are used to determine compressive and flexural strength, those values are tested on the same prism specimens for the cement mortar. The purpose of this study is to investigate the possible correlation between values of compressive strength obtained on half concrete prism (10 cmx10 cmx40 cm) after flexural test with compressive strength on standardized 15 cm and 10 cm cubes. Three concrete mixtures have been tested and every mixture had a different maximum grain size of aggregate, namely 8 mm, 16 mm and 31,5 mm. Same type and quantity of the cement are used in all mixtures with the same water/cement ratio. The workability of the fresh concrete was examined by using the slump-flow method. Nine specimens are prepared for each concrete mixture; three for every dimension. According to the obtained results, it can be assumed that there is a significant level of connection of compressive strength values between half-prism and both 10 cm and 15 cm cube specimens. Results showed there is a possibility of using half-prism concrete specimens after the flexural test for the evaluation of compressive strength. This would reduce the number of test samples and the problem of sample disposal after the test.

Keywords

• Compressive strength
• Flexural strength
• Size of the test specimen
• Concrete

References

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