The Effect of Coarse Aggregate Size on the Stress-strain Curves of Concrete under Uniaxial Compression

Abstract

In Hong Kong, concrete made with a maximum aggregate size of 10 mm and 20 mm is very popular, while little research has been conducted to investigate the effects of the maximum coarse aggregate size on the stress-strain curves of concrete under uniaxial compression. In the present study, a series of compressive tests were conducted on prismatic specimens made of normal strength concrete and high strength concrete (30 MPa - 90 MPa) with maximum aggregate sizes of 10 mm and 20 mm. Friction-reducing materials were used on the ends of the specimens to alleviate the effect of boundary constraints. The effect of the maximum aggregate size on the mechanical parameters such as the compressive strength, elastic modulus, strain at the peak stress, and the stress and strain at the inflection point were studied. Furthermore, a stress-strain model suitable for local concrete made with a maximum aggregate size of 10 mm and 20 mm was proposed.