Determination of the drying shrinkage and compressive strength of concrete by using nano-silica

The use of nano particles is one of the new technologies applied in concrete matrix. This study presents the experimented results of an investigation on the use of nS as a supplementary cementitious material to improve the performance of normal concrete. Three replacement levels of nS (i.e. 1, 3, and 5% by weight of the binder) were employed and compared with normal concrete without nS. Therefore, a total of 12 concrete mixtures were designed at three water-binder (w/b) ratios (i.e. 0.33, 0.45, and 0.55) with total cementations materials contents such as 380, 325 and 300 kg, respectively. The performance characteristics of the concretes such as compressive strength, drying shrinkage, and weight loss due to the corresponding drying were evaluated. The results revealed that the inclusion of nS significantly increased the drying shrinkage strain compared with normal concrete. Therewithal, an increasing in the compressive strength of the concrete was observed depending mainly on the replacement level of nS, w/b ratio, and the age of testing. For the same w/b ratio, increasing of nS content up to 3% yielded in higher compressive strength than that of concretes implemented by incorporating 0% and 5.0% nano-particles. Moreover, drying shrinkage and weight loss increased with the increase of w/b ratio and the addition of nS.