Effect of Limestone Powder and Gypsum on the Compressive Strength Mixture Design of Blast Furnace Slag Blended Cement Mortar

Abstract

Journal of Advanced AbstractThis paper investigates the compressive strength development of blast furnace slag (BFS) blended mortar mixtures incorporating various mineral admixtures, namely BFS, limestone powder (LSP), and gypsum (CS). BFS replacement ratios of 15, 20, and 25 wt.%; LSP replacement ratios of 2, 3, 4, and 5 wt.%; and a CS replacement ratio of 2 wt.% are employed to improve the strength of BFS blended mortar mixtures. The hydration reaction and products resulting from the use of cement, BFS, and mineral admixtures are quantitatively examined with respect to the XRD/Rietveld method in order to investigate the relationship between the produced hydrates and the strength. Experimental investigation reveals that the mortar mixture with BFS 15 wt.%, LSP 4 wt.%, and CS 2 wt.% exhibits similar compressive strength to an ordinary Portland cement mortar mixture. In addition, the strength is found to be decreased as the BFS replacement ratio increases. At a BFS replacement ratio above 20 wt.%, LSP affects the strength improvement of BFS cement and CS affects the initial strength improvement of BFS cement.

Study on Mechanical Properties of High Fine Silty Basalt Fiber Shotcrete Based on Orthogonal Design

“…15a shows that the 3 and 28 d compressive strengths first increase and then decrease with the increase of C/H, indicating that the optimal strengthening effect of C/H is not simply linear with the dosage. HFS fine powder can optimize the particle size of cementitious materials to improve the compacting degree of the system [32]. When it exceeds a certain limit, the physical filling effect of fine powder particles on the particle size optimization of cementitious materials is smaller than its dilution effect, which leads to the weakening of the skeleton function of sand particles and the difficulty in maintaining the strength improvement.…”

Study on the Influence of Minor Constituents in Blast Furnace Slag Rich Cement on the Thermal and Mechanical Properties of Concrete

“…The temperature was then gradually lowered and the specimens were demolded at 3 days of age, cut into 3 mm thick slices as the specimens used for analysis, immersed in acetone for 3 hours to stop hydration, and then subjected to analysis. XRD measurement and Rietveld analysis were performed on the specimens (Sagawa and Nawa, 2014;Kim et al 2017). XRD measurement was performed using a rotating specimen stage and high-speed solid state detector, using as conditions target CuKα, tube voltage of 40 kV, tube current of 15 mA, scanning range of 5 to 70 deg.…”

Impact of Superplasticizers on the Performance of Low-Grade Limestone-Based Cement Mixes

“…Two main observations due to the additions of gypsum to the limestone-based cement mixes are (i) an increase in the degree of the hydration of tricalcium silicate (C 3 S) due to the aluminate peak pushing beyond the silicate peak and (ii) an increase in the amount of ettringite crystals due to additional sulfate from the gypsum [ 16 ]. Furthermore, a suitable content of limestone and gypsum can have some positive influence on concrete properties, such as filler, nucleation, and chemical effects, as well as improving workability [ 17 ]. However, the optimal content of LGL–gypsum–cement blends still needs further study in concrete systems with a relatively low water/binder ratio and a high superplasticizer dose.…”