THE STUDY OF AUTOCLAVED CELLULOSE FIBER-REINFORCED CEMENT COMPOSITES

The effects of individual or combined addition of sodium water glass ( SWG), calcite and CaCl2 into the starting material, consisting of 92 w t.% of Portland cement with sand and 8 wt.% of cellulose fibers, were studied after autoclaving. Bending strength, bending toughness and mod ule of elasticity were determined. The optimal additions were either 2 6 wt.% of SWG and 10 wt.% of calcite (sample No. 4) or 5 wt.% of CaCl2 (sample No. 2). Autoclaved products were also investigated by X-ray d iffraction (XRD), mercury intrusion porosimetry (MIP) and scanning ele ctron microscopy (SEM). All results were compared to the product obtai ned without additions.