Effect of Fine Aggregates on Properties of Magnesium Potassium Phosphate Cement Mortar: Fid-Bau Portal

Effect of Fine Aggregates on Properties of Magnesium Potassium Phosphate Cement Mortar

Jianming, Y. / Tao, L. / Xuancheng, X.

This paper aims to investigate the effect of fine aggregates on properties of magnesium potassium phosphate cement (MKPC) mortar. River sand (RS), limestone sand (LS), and mixed aggregates (RS/LS mixture) were used to prepare MKPC mortar, respectively. Then, the fluidity, mechanical strength, shrinkage deformation, and hydration temperature of different MKPC mortars were tested. Compared with MKPC mortar prepared using RS, MKPC mortar prepared using LS has significantly higher 60-day flexural strength, slightly higher 60-day compressive strength and 60-day shrinkage strain, and lower 60-day flexural strength residual ratio under water curing condition. Compared with MKPC prepared using LS, MKPC mortar prepared using mixed aggregates has higher 60-day compressive strength, higher strength residual ratio under water curing condition, and lower 60-day shrinkage strain. Also, the effect of the ratio of aggregates to a binder (MKPC) on properties of MKPC mortar is investigated. Results show that the optimal aggregates to binder ratio for MKPC mortar prepared using mixed aggregates ( $W_{LS}$ to $W_{RS}$ ratio is $2 ∶ 1$ ) is $1.5 ∶ 1$ , resulting in high strength and low binder content of MKPC mortar. When $W_{LS}$ to $W_{RS}$ ratio is $2 ∶ 1$ and aggregates to binder ratio is $1.5 ∶ 1$ , 60-day flexural and compressive strengths of MKPC mortar are greater than 40% higher than that of MKPC mortar prepared using RS; 60-day flexural and compressive strength residual ratios of it are above 80%, and its shrinkage deformation is close to that of MKPC mortar prepared using RS.