Research of Mortar Containing Phosphorous Slag and Calcium Carbonate Nanoparticles

Huashan Yang,Yujun Che

doi:10.1155/2019/5830201

Abstract

Ground phosphorous slag (PS) has not been widely used in construction due to its negative effects on the early-age performances of cementitious materials. The effects of calcium carbonate nanoparticles (NC) on strength development of mortar containing high content of PS were investigated at different curing ages. The NC was incorporated at 2% as partial mass replacements for binder. Hydration products and microstructure characterization was examined by X-ray diffraction (XRD), differential thermal gravity (DTG), thermogravimetric (TG), and scanning electron microscopy (SEM) analysis. Test results showed that NC improved both flexural and compressive strength of mortar containing high content of PS at 7, 28, 56, and 90 days. XRD, DTG-TG, and SEM analysis confirmed the filling effect of NC. Furthermore, the formation of the carboaluminate even at later age also improved the microstructure of mortar, which created a denser microstructure.

Highlights

Sustainable development and environmental protection of concrete industry have attracted a growing attention [1, 2]
It is reported that partially replacing clinker by mineral admixtures, such as fly ash (FA), granulated blast furnace slag (GBFS), silica fume (SF), copper slag (CS), ground phosphorous slag (PS), and limestone powder (LS), is an effective way to alleviate the environmental burden [2,3,4,5]. ese mineral admixtures improve the mechanical performances and durability of cementitious materials [6,7,8,9]
Portland cement (PC, P.I 42.5), PS, NC, silica sand, and deionized water were used in this experiment. e chemical compositions of PC, PS, and NC as given in Table 1 were determined by X-ray fluorescence

Summary

Huashan Yang and Yujun Che

Ground phosphorous slag (PS) has not been widely used in construction due to its negative effects on the early-age performances of cementitious materials. E effects of calcium carbonate nanoparticles (NC) on strength development of mortar containing high content of PS were investigated at different curing ages. Hydration products and microstructure characterization was examined by X-ray diffraction (XRD), differential thermal gravity (DTG), thermogravimetric (TG), and scanning electron microscopy (SEM) analysis. Test results showed that NC improved both flexural and compressive strength of mortar containing high content of PS at 7, 28, 56, and 90 days. XRD, DTG-TG, and SEM analysis confirmed the filling effect of NC. The formation of the carboaluminate even at later age improved the microstructure of mortar, which created a denser microstructure

Introduction

Materials and Methods

Results and Discussion

Sand to binder ratio

PS C