Abstract

The effect of wheat stalk ash (WSA) on the physical, chemical and mechanical properties as well as the hydration of the cement pastes containing it was evaluated, and so it can provide a necessary theoretical basis and a practical guiding significance for practical engineering. It is concluded that WSA could be partially added to cement without any adverse effect on its specific properties, particularly the compressive strength. The free lime content, Ca (OH)2 is obviously decreased with WSA. The optimum WSA content was 20wt. %, and more than this amount, the specific properties of cement were declined. The polyprobyene admixture (PPP) is the mean reason responsible for the modification and improving most of physical, chemical, and mechanical properties of the hardened cement pastes. The pozzolanic reactions of WSA with Ca (OH)2 played a vital role to form additional CSH gel-phases that support and enhance the specific properties of the cement.

Keywords: Wheat straw ash; Cement; Setting; Density; Porosity; Strength

Abbreviations: C: CaO, S: SiO₂, A: Al₂O₃, F: Fe₂O₃, H: H₂O, CH: Ca (OH)₂, Calcium Silicate Hydrate (CSH), Silica Nano Particles (SNP)