The tensile strength of cement paste was increased by 56% and the modulus and ductility were increased by 39% by using silane-treated carbon fibers and silane-treated silica fume, relative to the values for cement paste with as-received carbon fibers and as-received silica fume. Silane treatment of fibers and silica fume contributed about equally to the strengthening. Silane treatment of fibers...

Modification of sodium lignosulfonate (SLS) via combined oxidationsulfomethylation was employed to prepare concrete superplasticizer. It was found that the oxidation of SLS by peroxyacetic acid facilitated the subsequent sulfomethylation. After modification, both the molecular weight and sulfo group content were significantly increased, and thus the performance of SLS as water reducer was impro...

The recycling of waste glass is a major problem for municipalities worldwide. The problem concerns especially colored waste glass which, due to its low recycling rate as result of high level of impurity, has mostly been dumped into landfills. In recent years, a new use was found for it: instead of creating waste, it can be recycled as an additive in building materials. The aim of the study was ...

The concurrent goals of cement hydration are to percolate (bridge) the original cement particles into a load-bearing network and to depercolate (dam) the original water-filled capillary porosity. The initial volume, particle size distribution, and flocculation/dispersion state of the cement particles have a large influence on both hydration rates and microstructure development. Likewise, the ca...

This paper investigates the effectiveness of two zeolites with different reactive silica content, fly ash (FA), blast furnace slag (BFC), silica fume (SF), and micronized calcite (MC) in reducing expansion of concrete due to alkali-silica reaction. Also in this research, effects of three different cement usages were investigated by using accelerated mortar bar method, ASTM C1260. Five different...

In a pioneering work, Powers and Brownyard (1948) were the first to systematically investigate the reaction of cement and water and the formation of cement paste. In the late 1940s they presented a thorough model of the cement paste, in which unreacted water and cement, the hydration product, and (gel and capillary) porosity were considered. Via extensive and carefully executed experiments majo...