Mortar In Presence Research Articles

Experimental study on strength and microstructure of mortar in presence of micro and nano-silica

Abstract Sustainable construction practices require cementitious materials with high strength that is strongly dependent upon the nature of binding materials and pore structure. The physico-chemical properties of these materials can be tailored suitably by preferential substitution of cement by materials having comparatively small particle size resulting in improved pore structure. This study is aimed to investigate strength and microstructure of the preferentially substituted cement mortars with incorporation of microsilica (MS), nanosilica (NS) and their combined use at 3, 7 and 28 days of curing. The substituent MS (5.0–20%) and NS (0.5–1.25%) have been used at a water binder ratio of 0.5. The specimens were analyzed for the fresh (consistency, setting time, flow) and hardened (compressive and split tensile strength) properties and a correlation between compressive and split tensile strength was obtained. Mortar containing NS was found to develop better strength as compared to the mortar containing MS. The optimum usage of MS with incorporation of NS was further found to increase the strength of mortar significantly. SEM-EDX was used for the analysis of the microstructure of the specimens and the correlation between Ca and Si content was used to analyze the cement matrix. The findings show that the optimized usage of micro and nano silica can give beneficial effects to improve the fresh properties as well as strength with dense microstructure.

Garlic Catalyzed and Grindstone Assisted Solvent Free Green Synthesis of Pharmaceutically important Schiff Bases

Present research work demonstrates the use of garlic as natural biocatalyst for green synthesis of a series of Schiff bases which are an important class of pharmaceutically important compounds, employing p-toluidine and variety of aromatic aldehydes as reactants. The products were obtained with good percentage of yield by simply grinding the reactants together with pestle in a mortar in presence of a piece of garlic in a completely solvent free condition. The synthesized crude products were purified by recrystallization from hot ethanol to obtain pure Schiff bases which were characterized by melting point, FTIR, 1H-NMR and 13C-NMR. Through this work, a very simple, eco-friendly, effective, economic and new methodology is developed for synthesis of Schiff bases.

Evaluation of inherent factors on flowability, cohesiveness and strength of cementitious mortar in presence of zeolite powder

Abstract Due to the pozzolanicity and grindability, zeolite had undeniable advantages to be used as a supplementary cementitious material for reduction of cement consumption and carbon footprint of concrete production. Since the study on the effects of zeolite powder (ZP) addition on rheological and hardened properties of cementitious mortar system was rare in literature, the purpose of this study was undertaken to reveal this subject. A total of 25 mortar mixes with various ZP contents at various water/binder (W/B) ratios were prepared and subjected to flowability, cohesiveness, adhesiveness compressive strength and permeable porosity tests. In-depth analysis revealed that the water film thickness (WFT) combined the effect of solid packing density, water demand and solid surface area, and hence governed the rheological property of the cementitious composite; the permeable porosity was proved to be the key governing parameter for the hardened performance of cementitious mortar. Addition of ZP exerted its influence on the performance of mortar via changing the WFT and permeable porosity of the cementitious composite system. For achieving a sound balance between the rheological and mechanical property of cementitious composite, a lower permeable porosity at the same WFT or a higher WFT at the same permeable porosity was pursued. The regression analysis results of concurrent permeable porosity-WFT quantified the positive effect of the partial substitution of Portland cement by 5–10% of ZP was affordable in all aspects.

Durability of Mortar in Presence of Rice Husk Ash

Durability of Mortar in Presence of Rice Husk Ash