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Alkali-activated materials (AAMs) are regarded as an alternative cementitious material for Portland cement with regards to sustainable development in construction. The purpose of this work is to investigate the properties of activated blast-furnace slag (BFS)–steel slag (SS) with sodium carbonate (NC), taking into account BFS fineness and Na2O equivalent. The hydration was investigated by rheological behavior and pH development. The hydrates were characterized by TG-DTG and XRD, and the microstructure was analyzed by SEM and MIP. Results showed that the rheology of activated BFS-SS pastes was well-fitted with the H-B model and affected by BFS fineness and NC mixture ratio. It was found that BFS fineness and NC ratio played a crucial role in the initial alkalinity of SS-BFS-based pastes. As such, lower BFS fineness and higher NC ratio can dramatically accelerate the formation of reaction products to endow higher mechanical strength of BFS-SS pastes. However, the effect of NC ratio on the microstructure development of BFS-SS based AAMs was more obvious than BFS fineness. [ABSTRACT FROM AUTHOR]

The application of ultrafine ground-granulated blast-furnace slag (GGBFS) in concrete becomes widely used for high performance and environmental sustainability. The form of ultrafine slag (UFS) used in concrete is powder for convenience of transport and store. Drying-grinding-drying processes are needed before the application for wet emission. This paper aims at exploring the performances of concrete blended with GGBFS in form of slurry. The ultrafine slag slurry (UFSS) was obtained by the process of grinding the original slag in a wet ball mill, which was mixed in concrete directly. The durations of grinding were 20 min, 40 min, and 60 min which were used to replace Portland cement with different percentages, namely, 20, 35, and 50, and were designed to compare cement with original slag concrete. The workability was investigated in terms of fluidity. Microstructure and pore structure were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP). The fluidity of concrete mixed with UFSS is deteriorated slightly. The microstructure and early strength were obviously improved with the grind duration extended. [ABSTRACT FROM AUTHOR]

• Wet-grinding can effectively reduce the particle size of PS, but will lead to the gradual increase of phosphorus leaching. • Krstulovic-Dabic model can well simulate the hydration process of wet grinding phosphorous slag with paste. • The retarding effect of phosphorus decreased nucleation and crystal growth rates, thus increasing the setting time and the length of NG stage. • The utilization of wet-grinding phosphorus residue can bring significant economic and environmental benefits. In the study, the influencing factors of wet-grinding phosphorus slag (PS) and reaction kinetics on the early hydration of Portland cement were investigated. The results indicated that wet-grinding could decrease fineness efficiently while it enhanced the dissolution of phosphorus elements in PS slurry. The incorporation of PS led to lengthening the setting time for cement-based samples but the rising tendency was cut down. The Krstulovic–Dabic model could well explore the hydration process of the paste samples mixed with wet-grinding PS, but not simulate the paste incorporated with raw PS. Moreover, wet-grinding enhanced the hydration degree and rate in the nucleation and crystal growth stage, while it may shorten the duration time of the phase boundary reaction stage and decrease the hydration rate in the diffusion reaction stage. The research afforded a theoretical basis for using wet-grinding phosphorus slag as an admixture that would be eco-friendly and cost-effective. Based on the evaluation of the benefits, the wet-grinding treatment of PS and utilization of the PS slurry to replace cement could reconcile economic feasibility with environmental benefit and was an innovative approach to the reuse of PS. [ABSTRACT FROM AUTHOR]

• The particle size of CWS after wet-grinding decreased (D50 = 0.7 μm) and the pH value increased. • The C S H gel of CWS increased after wet-grinding. • The addition of CSW has significantly improved the early hydration rate of cement-based materials. Adding nano particles were supposed to displace steaming curing in manufacturing prefabricated components of concrete for avoiding thermal damage. Nevertheless, there were not yet appropriate nano particles adapted for practical production, and the main reason was those existing nano particles involved complicated technological processes and high costs. Last incompatibility with cement-based materials confined to its application. In this study, a new early strength agent was prepared by wet-grinding concrete waste slurry (CWS). The physicochemical properties of CWS after wet-grinding were analyzed by means of XRD, the particle size distribution (PSD), ICP, SEM, pH, resistivity, and TG. Finally, the effects of CWS on the early hydration processes and mechanical properties of cement-based materials were explored by means of setting time, hydration heat, chemical shrinkage, resistivity, mechanical properties, and MIP. The results showed that the particle size of CWS after wet-grinding decreased (D50 = 0.7 μm). Meanwhile, the surface area and the dissolution of alkaline ions in the solution increased, which provided nucleation sites and the alkaline environment for the early hydration of cement-based materials. Moreover, the early hydration rate of cement and mechanical properties were greatly improved. For instance, the cumulative heat release at 12 h increased by 111.7%, the induction period was shortened, the gel hole increased by 8% in 12 h, the large hole decreased by 37%, and the initial and final coagulation time was shortened by >30%, the compressive strength at 12 h increased by 406.3%, and the compressive strength was basically equivalent in the later period. The research in this paper showed that it was feasible to prepare the new early strength agent from CWS through the wet-grinding treatment, which provided a new reference for the green development of the prefabricated component industry. [ABSTRACT FROM AUTHOR]

Beta-hemihydrate phosphogypsum (β-HPG) is a low-carbon cementitious material used in construction. Nevertheless, the poor water resistance and low mechanical strength of β-HPG limit its utilization. In this study, two low-calcium fly ash (FA) slurries with median particle sizes of 1.83 μm and 1.14 μm were prepared using a wet-grinding process for the improvement of β-HPG, and the mechanical strength and softening coefficient were tested to assess the effect. The results show that wet-ground low-calcium FA can significantly enhance the mechanical strength and softening coefficient of β-HPG. Compared with specimens without wet-ground low-calcium FA, the dry compressive strength and softening coefficient of specimens with 30% wet-ground low-calcium FA (D 50 =1.14 μm) increased by 104.9% and 71.8%, respectively. It is worth noting that the 1 d compressive strength also increased by 11.9%. Specifically, wet-ground low-calcium can increase the pH value and conductivity of the FA slurry, further accelerate the hydration process of FA in β-HPG, forming more ettringite and gels to fill in the pores between dihydrate gypsum (DH) crystal, and reducing the larger pores in the hardened paste. This study can develop a high-performance cementitious material that will enable the effective use of β-HPG. • Wet-ground low-calcium FA can increase the mechanical properties of β-HPG. • As the fineness of FA increases, the heat flow will be delayed. • Wet-ground low-calcium FA improves the microstructure and pore structure. [ABSTRACT FROM AUTHOR]

The optimization of mechanical properties and regulation in setting time of beta-hemihydrate phosphogypsum (β-HPG) are the key to its utilization in building materials. Calcium sulfoaluminate cement (SAC) can significantly enhance the mechanical properties of β-HPG to form a gypsum-based-composite binder, but have little effect on regulating the setting time. Retarders can regulate the setting time of β-HPG but decrease its mechanical properties. However, the synergistic modification mechanism of retarders and SAC on β-HPG has not been clarified. In this paper, the effects of protein retarder (SC) and citric acid (CA) on the setting time, hydration heat, mechanical properties and microstructure of the β-HPG-SAC composite binder were studied systematically. The results show that incorporating SC and CA can effectively regulate the setting time, but the effects on the mechanical properties differ. SC has a certain optimization effect on mechanical properties at low content, but has a negative effect when the content is over 0.2%, while CA has a continuous negative effect with its increasing content. Specifically, SC hinders the formation of the crystalline structure to a certain extent, and makes the crystallization of β-HPG and the hydration of SAC synergistic, while CA delays the hydration process of β-HPG and SAC simultaneously. Different from SC, CA can inhibit the growth of dihydrate gypsum (DH) crystals in the C-axis direction, transforming long rod crystals into short columns, eventually forming a looser microstructure and decreasing mechanical properties. This work provides an effective method for the modification of β-HPG and the high value-added resource utilization of PG. • SC and CA can effectively regulate the setting time of the composite. • SC has a certain optimization effect on mechanical properties at low content. • The contents of AFt are decreased by the incorporation of retarders. [ABSTRACT FROM AUTHOR]

• A preparation process of high value-added specific additive was designed from plastic waste concrete. • The 12 h compressive strength of cement was increased by 356 % after adding the PWC based additive. • The addition of PWC additive can optimize the pore structure and improved the compactness of matrix. • The resistance to chloride ion penetration at the later stage was also enhanced. Plastic waste concrete is an alkaline solid–liquid mixed waste generated in the concrete production process. The recycling of plastic waste concrete in building materials can help reduce environmental pollution. In present work, wet-grinding process was utilized to set up a high-value added wet-grinding plastic waste concrete (WPWC) based specific additive with a D 50 of 1.07 μm. The physical and chemical properties of WPWC based additive and its effects on the rheological property, hydration process, compressive strength, microstructure and permeability of Portland cement were investigated. The results showed that after adding WPWC additive, the compressive strength of 12 h was increased by 356 %, and more hydration products were produced. Different from common early-strength agents, the addition of WPWC additive can provide combined effects of nucleation induction and physical filling, which optimized the pore structure and improved the compactness of matrix. In addition, the resistance to chloride ion penetration at the later stage was also enhanced. This indicated that the incorporation of WPWC additive is an effective method to improve both the early strength and late permeability of cement. [ABSTRACT FROM AUTHOR]

Highlight • TEA and TIPA noticeably hindered the formation of C-(A)S-H gel at 7 d age. • TEA accelerated the formation of hydrotalcite-like phase at 7 d age. • TEA and TIPA could expedite the dissolution of ferric phase in WGGBS. • 28 d strength of 10.0% cement-90.0% WGGBS-0.05%TEA reached 43.7 MPa. Abstract In this study, a commercially available ground granulated blast-furnace slag (GGBS) was further processed by wet grinding, and WGGBS (wet-grinded GGBS) slurry with superfine particles was obtained. To avoid self-hydration of slag and augment the grinding efficiency, one commercially available polycarboxylate superplasticizer was added. The binder, composed of 10.0% cement and 90.0% WGGBS with the addition of 0.05% triethanolamine (TEA) and 0.05% triisopropanolamine (TIPA), was designed; the cement was added to provide alkali environment and calcium ions, and organic alkali was used to promote the dissolution of GGBS. The compressive strength of mortar and hydration mechanism was investigated. The results showed that wet grinding exhibited high grinding efficiency; D(50) value of particle size distribution of WGGBS was reduced from 18 μm to 2.10 μm by wet grinding for one hour. Compressive strength of hardened WGGBS mortar was 20 MPa and 28 MPa at 7 d and 28 d, and 10% cement replacement ratio of the WGGBS increased the strength to 24.6 MP at 7 d and 32.2 MPa at 28 d. Furthermore, in C-WGGBS, 0.05% TEA increased the 7 d strength by 23%, with the value of 30.27 MPa, but 0.05%TIPA slightly reduced it to 23.5 MPa, with a decrease by 5%. Mechanism behind the increase was due to the accelerated formation of hydrotalcite-like phase, despite the retarding effect on formation of C-(A)S-H gel; the slight decline by TIPA was mainly because of the retarding effect of formation of C-(A)S-H gel as well as its air-entraining effect. Moreover, both TEA and TIPA increased the 28 d strength of cement-WGGBS system, because TEA and TIPA were able to facilitate ferric and aluminum dissolution and expedite the formation of C-(A)S-H gel as well as hydrotalcite-like phase. Additionally, it was worth noting that 0.05% TEA could make 28 d strength of the binder, composed of only 10% cement, reach 43.7 MPa, in accordance with the requirement of 42.5 grade cement. [ABSTRACT FROM AUTHOR]

Geopolymer is a potential substitute for high-emission cement production. Therefore, the use of fly ash with high emission as a geopolymer is an environmentally friendly and inexpensive direction. However, fly ash (FA) is a high amorphous precursor with low pozzolanic reactivity making it difficult to be activated by calcium hydroxide. In this study, the coupling of wet-milling mechanical force and calcium hydroxide was used to prepare high-performance alkaline calcium activated geopolymers. Two kinds of FA slurries with different particle sizes of D 50 = 2.96 μm and 14.2 μm were prepared, activated by calcium hydroxide (CH) with the content of 4%, 11% and 19%. Results indicated that the increase of calcium hydroxide content was beneficial to developing strength, effectively improving the chloride resistance, compacting the microstructure, but increasing the autogenous shrinkage of the geopolymers. These improvements are especially apparent in the wet-milled fly ash geopolymers (WFA) due to the pre-depolymerization implemented by wet-milled mechanical forces, and coupled with the activation effect of CH to improve the depolymerization efficiency and condensation reaction. The compressive strength of WF-CH-19 was three times higher than that of FA-CH-19, reaching 29.3 MPa at 28 d, and the compressive strength growth of WF-CH-11 even reached 591.67% at 1 d. Meanwhile, the main chain length (MCL) and Al/Si of calcium silicate hydrates were clearly improved, and pore structure was significantly refined with capillary pore increased from 29.79% to 89.23%. In addition, FA and WFA geopolymers have significant advantages over Portland cement in the environmental impact indicators such as E-energy and E-CO 2. • Low calcium FA geopolymer was prepared by coupling wet-milling mechanical force and CH activation. • Compressive strength of WFA-CH-19% reached 29.3 MPa at 28 d, three times of FA-CH-19%. • The growth rate of compressive strength is higher at low CH content. • The critical pore size is reduced from 66.92 nm to 24.59 nm in WF-CH-19%. • Significant increase in MCL and Al/Si ratio are found in WFA geopolymers. [ABSTRACT FROM AUTHOR]

• Nano C-S-H seeds with D50 = 420 nm were prepared from GGBS and CS by wet grinding. • Nano C-S-H seeds notably augmented the compressive strength of PC. • Nano C-S-H seeds accelerated PC hydration and refined the pore structure. • The results provided a new approach to prepare nano C-S-H seeds. In the present study, to enhance the early mechanical properties of Portland cement (PC), ground granulated blast-furnace slag (GGBS) and carbide slag (CS) were cured and treated by wet grinding to prepare nano C-S-H seeds (NCSH). The properties of NCSH were characterized in details. NCSH-PC system was designed, and the dosage of NCSH was chosen as 0%, 0.5%, 1%, 2% and 4% of cement. Compressive strength and the setting time of NCSH-PC system were examined. The related mechanism was analyzed by XRD, hydration heat, 29Si NMR, TG-DTG and MIP. Results exhibited that NCSH slurry with D50 = 420 nm was obtained, and it notably augmented the early compressive strength of PC mortars, noting that 4% NCSH enhanced the compressive strength by 131.4% at 12 h. Moreover, the final setting time of PC pastes was shortened by 46.3% by adding 4% NCSH. The reason was that NCSH greatly accelerated PC hydration and further expedited the hydrates formation; also, the pore structure was refined owing to the filling effect offered by NCSH, noticing 4% NCSH reduced the total porosity from 22.8% to 19.7% at 12 h. Such results suggested a novel method to prepare NCSH, and it was expected to act as an accelerator in PC system. [ABSTRACT FROM AUTHOR]

• Superfine cement was obtained by wet grinding process. • Superfine cement could enhance the strength of HVFA system. • This kind of binders showed low carbon emissions and costs. The use of high-volume fly ash (HVFA) in cement-based materials can significantly reduce the CO 2 emissions. Nevertheless, slow strength development becomes the barrier for HVFA system, and the main reason is because the low alkalinity offered by Portland cement (PC) cannot efficiently activate the pozzolanic reaction of FA. In this study, wet grinding was used to process PC and obtain superfine particles, with intention to promote the hydration of PC and offer more CH for FA activation. HVFA (50% PC and 50% FA) system was designed, and 0–15% wet grinded cement (WGC) was used to replace PC. The effects of WGC on HVFA system were investigated; the CO 2 emissions and costs of WGC-HVFA system were calculated. Results showed that the superfine cement with D50 = 3.17 μm was obtained by wet grinding. The compressive strength of HVFA mortars without WGC was 14.3 MPa and 33.5 MPa at 3 d and 28 d age, while 15% WGC enhanced the compressive strength of the mortars to 22.0 MPa and 46.6 MPa, respectively. In addition, CO 2 emissions and costs of the HVFA system containing 15% WGC were 477 kg/t and 347.5 RMB/t, which were much lower than that of PC system. Such results proposed an innovative approach to enhance the compressive strength of HVFA system, with great potential in low carbon cementitious materials. [ABSTRACT FROM AUTHOR]

• Wet grinding could refine waste concrete recycled powder (RP) to submicron particles. • 2~6% submicron RP enhanced the early hydration of plain PC and GBFS/FA-PC systems. • This paper was expected to develop a novel approach for the utilization of RP. Utilization of waste concrete recycled powder (RP) in cementitious materials faced enormous challenge, because of low activity and huge water demand. In this paper, RP was treated by wet grinding to prepare submicron-RP (SRP), and then SRP was used as an accelerator in various cementitious systems, including Portland cement system (PC), PC-granulated blast furnace slag (PC-GBFS), and PC-fly ash (PC-FA) system. The compressive strength, hydration heat, hydration products, and microstructure of these systems were studied. Results showed that SRP with an average diameter of 594 nm was obtained by wet grinding. In PC paste, at the age of 12 h, 6% SRP could augment the compressive strength by 150% and hydration heat by 100%, in comparison with the paste without SRP; in PC-GGBS or PC-FA system, the similar results were also found. The reason was because of the excellent nucleation effect to significantly facilitate the hydration of PC and promote the formation of hydrates; moreover, due to the filling effect of SRP, the microstructure of hardened pastes was refined. The research could provide a novel approach for the utilization of RP in precast engineering. [ABSTRACT FROM AUTHOR]

• D50 of raw steel slag decreased to around 3 μm by wet grinding. • Compressive strength of 3 μm-40% can reach the level of cement at 60 d. • Increased strength was ascribed to decreasing harmful pores and increasing less harm pores. Steel slag is a solid waste generated from the steelmaking process. With a very low utilization rate of 30% in China, a high discharging cost of steel slag is inevitable so that it is imperative to dispose of steel slag by new technology. In this study, steel slag was refined by wet-grinding technology to apply on cement. The results showed that the initial setting time and final setting time were prolonged by the increased dosage of 3 μm steel slag. Although the viscosity of wet-grinding steel slag – cement specimens increased significantly, the shear-thinning phenomenon happened by mechanical mixing. The wet-grinding specimens presented a higher hydration heat than that of raw steel slag specimens, and the microstructure of 3 μm-40% (3 μm steel slag mixed with cement as a dosage of 40%) is much denser and show more hydration products than that of raw-40% (raw steel slag mixed with cement as a dosage of 40%) which results in an enhanced compressive strength that could be guaranteed by the dosage of 20% (3 d), 30% (28 d) and 40% (60 d) under the condition of 3 μm steel slag incorporation with lower autogenous shrinkage. Hemicarboaluminate peak was found in wet-grinding specimens that show a higher calcium sulphoaluminate to calcium. The wet-grinding steel slag CO 2 emission and cost showed a downward trend compared with cement. [ABSTRACT FROM AUTHOR]

Utilization of recycled powder (RP) from construction and demolition wastes into construction projects would bring great economic and environmental benefits. In this research, RP was prepared from hardened cement paste by wet grinding (i.e. WGRP) in the laboratory, and an attempt to utilize these nano particles as an accelerator for facilitating Portland cement (PC) hydration was done. The basic properties of WGRP were characterized, and the effect of WGRP on the properties of PC was studied, including setting time, compressive strength, and permeability. Related mechanisms were discussed by X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Nuclear Magnetic Resonance (NMR), and Mercury intrusion porosimetry (MIP). Results showed that WGRP with median particle size (D50) of 249 nm was prepared. The addition of WGRP accelerated the setting process of PC pastes, and significantly augmented the early strength and impermeability of PC mortars. 4.0% WGRP shortened the final setting time by 175 min and increased the 12 h compressive strength by 180%. Due to the brilliant nucleation seed effect of WGRP, the release of PC hydration heat was greatly facilitated, and the inducing period almost disappeared; the formation of hydrates was accelerated, resulting in a higher hydration degree at the early age. Moreover, WGRP reduced the porosity of PC pastes and increased the harmless pore volume fraction. Such results suggested that WGRP expected to be utilized as an accelerator in PC. [ABSTRACT FROM AUTHOR]

• Nano-carbide slag seed was prepared with wet-grinding method. • The initial and final setting time was greatly shortened by 61.4% and 51.7%. • The early-age hydration kinetic of cement was notably accelerated by nano-CS seed. • The 8-hour compressive strength was greatly enhanced by the nano-CS seed by 3350%. In present work, a novel nano-CS seed was prepared by wet-grinding method and added to cement to accelerate the early hydration. With 5% nano-CS seed, the initial and final setting time was clearly shortened by 61.4% and 51.7% respectively; the dormant period and the main hydration peak was notably advanced by 52.9% and 43.5% respectively. Early compressive strength, especially the 8-hour strength, was greatly promoted by the nano-CS seed by 3350%, with 5% nano-CS seed. It was speculated that the early-hydration and early-strength was accelerated by weakening the electrical double layer shielded around the silicate phase, thus shortening the dormant period. Results highlighted that the prepared nano-CS seed in present work is expected to be practically used as a new type accelerator. [ABSTRACT FROM AUTHOR]

Industrial wastes consumed by the preparation of building materials is a potential method to ensure the sustainable development. In this study, lithium slag (LS), as the by-product of lithium salts production, was treated by wet grinding process to prepare micro particles and used to expedite the early hydration of Portland cement (PC). The physical-chemical properties of micro-lithium slag (micro-LS) was characterized comprehensively. Binary system of PC and micro-LS was designed and its compressive strength at 16 h, 1day, and 28 days was measured. The hydration process was observed by hydration heat. Hydrates trait was investigated by XRD, TG-DTG, and NMR; pores structure was estimated by MIP and SEM. Results showed that the micro-LS with D50 = 300 nm was obtained by wet grinding, in which the crystalline was far lower than the amorphous phases. More importantly, micro-LS could significantly promote the early strength of PC. 4.0% dosage increased the strength by almost 3 times at 16 h and by more than 50% at 1 day; 28 days strength was also increased by 28%, indicating that micro-LS expected to be used as an excellent accelerator for PC. The great improvement was mainly contributed to the nucleation inducing effect on hydration, the refined pore structure, and the high pozzolanic reactivity of micro-LS. The research suggested an innovation method for the utilization of LS. • Lithium slag with D50 = 300 nm could be prepared via wet-grinding. • The micro-LS could act as an excellent accelerator for PC hydration. • A novel way to dispose lithium slag was suggested. [ABSTRACT FROM AUTHOR]

Concrete slurry waste is a dewatered solid residue generated from the production of concrete. The high discharging cost of concrete slurry waste strikes the concrete industry so that it is imperative to find an effective method to dispose concrete slurry waste. This study is conducted to utilise wet-milling to refine concrete slurry waste to partially replace the use of cement. In this method, concrete slurry waste was considered as filler and nucleus site to densify the microstructure of paste by filling the space and accelerating hydration. The results showed that both the initial and final setting time gradually decreased as the wet-milling concrete slurry waste dosage increased. The W15 mixture presented a cumulative heat evolution lower than that of the W10 mixture, however, all the mixtures with wet-milling concrete slurry waste showed cumulative heat evolution higher than the reference mixture. Similar to heat evolution results, compressive strength showed a positive effect when the wet-milling concrete slurry waste dosage was lower than 15%. Mercury intrusion porosimetry analysis results suggested that wet-milling concrete slurry waste can refine pore structure of hardening cement paste. The wet-milling concrete slurry waste energy intensity, carbon emission and cost showed a downward trend according to the quantitative calculation compared to Portland cement. Image 103 • Concrete slurry waste are refined through wet-milling. • The reaction degree and microstructure of samples develop at a faster rate. • Mixes containing WCSW can exhibit a qualified compressive strength. • The environmental impact is relieved after substituting cement with WCSW. [ABSTRACT FROM AUTHOR]

• D50 of raw materials decreased to around 3 μm by wet grinding. • Strength of WGGBS increased clearly by the use of wet grinded waste gypsum. • Increased strength was attributed to the evolution of hydrates and porosity. Replacement of Portland cement by industrial wastes has been accepted as a potential way to reduce carbon emissions. Ground granulated blast furnace slag (GGBS), desulphurization gypsum (DG), and phosphogypsum (PG), known as the common industrial wastes, were used in this study. Binders comprised of GGBS and waste gypsum were designed to develop a novel low carbon material; in order to promote the reactivity raw materials were processed by wet grinding. Compressive strength was examined and hydration process was researched by XRD, TG, NMR, SEM, and MIP. Results showed that wet grinded PG (WGPG) and wet grinded DG (WGDG) were able to greatly augment compressive strength of wet grinded GGBS (WGS) system. The reasons were attributed to the accelerated formation of ettringite and the reduced porosity. On the one hand, the presence of ettringite could construct the crystal skeleton resulted in the hardening of system accelerated. On the other hand, the constantly produced C-S-H gel densified the microstructure and decreased the porosity significantly. Moreover, in comparison with WGDG-WGS system, the early strength of WGPG-WGS system was lower caused by the retardation effect of phosphorus in PG. Results was expected to be used for the design of low carbon materials. [ABSTRACT FROM AUTHOR]