Experimental study on stress-strain curves of seawater sea-sand concrete under uniaxial compression with different strain rates

Abstract

In order to investigate the mechanical properties of seawater sea-sand concrete (SSC) under uniaxial compression, the SSC prisms with different mix proportions are designed and prepared, and the compressive strength and stress-strain curves under uniaxial compression are tested, in which five loading strain rates 10−5/s, 10−4/s, 10−3/s, 10−2/s, and 10−1/s are selected. The failure patterns of the SSC specimens under different strain rates are discussed, and the peak stress, peak strain (strain at the peak stress), elastic modulus, and ultimate strain are analyzed. The influence of the strain rate and the shell particle content on the stress-strain curves is intensively evaluated. It shows that the peak stress and elastic modulus increase with an increasing strain rate while the peak strain and ultimate strain have no obvious trend. Additionally, the shell particles seem to have contributions to the increase of the compressive strength of SSC base on the test results of cube and prism specimens, but further considerations about this phenomenon are necessary. Finally, the dynamic increase factor (DIF) of characteristic indices of SSC is put forward.