Hydration properties of belite cement prepared by lime-hydrothermal treatment of Saudi basaltic volcanic ash and glass

Abstract

In this study, lime, volcanic ash, glass, and OPC were used to prepare belite, belite/OPC blended, and volcanic ash/OPC blended cements. The hydrothermal treatment of volcanic ash/lime mixes at 190 °C for 3.5 h followed by calcination at 600 °C for 3 h. The heat of hydration of cements was measured, and hydration characteristics were assessed by combined water, compressive strength, bulk density, and total porosity measurements. The microstructural changes with hydration progress were monitored by XRD, TGA, FTIR, and SEM techniques. Hydrated calcium silicate is formed by hydrothermal treatment and was transformed to belite by calcination. The heat of hydration of plain belite cements increases with increasing lime content, confirming its unsuitability for massive concrete applications. Whereas, belite/OPC blended cements exhibit a lower heat of hydration to be suitable for applications requiring moderate heat of hydration and low initial strength gain. The rate of hydration of belite cement improves both by increasing the content of lime to 25–30% as well as blending with OPC. Volcanic ash/OPC blended cement has an average compressive strength between plain belite cement and belite/OPC blended cement. This research provides valuable insights for practical application of prepared belite cement in the construction.

Introduction

The cement industry is one of the heavy industries that consume energy resources and pollute the environment. In terms of the consumption of energy resources, the total energy needed to manufacture cement is estimated at 110 kW/t. The grinding and processing of raw materials consumes about 30%, the clinker production process consumes about 30%, and the clinker grinding process consumes about 40% of the total energy required for manufacturing¹. Regarding environmental pollution, the average CO₂ emission from the cement industry is about 0.95 tons of CO₂ per ton². Belite cement, produced by hydrothermal treatment of lime-silicate mixtures followed by firing at temperatures not exceeding 800 °C, is distinguished by a reduced energy footprint and lower CO₂ emissions compared to conventional Portland cement³. This process yields a cementitious binder where the primary hydraulic phase is belite (dicalcium silicate, C₂S), which predominates over other phases⁴. Chemically, the cement is rich in calcium and silica, with the hydrothermal treatment promoting the formation of reactive, low-crystallinity belite alongside a modest amount of amorphous calcium silicate hydrate, CSH⁵. The mineralogical composition typically includes poorly crystalline belite, minor residual lime, and trace amounts of secondary phases resulting from incomplete reactions. As a result, belite cement exhibits slower early strength development but achieves durable, long-term performance, making it an attractive option for sustainable construction practices where lower thermal processing and reduced environmental impact are desired⁶. The technology of producing belite cement consists of two steps: hydrothermal treatment of lime-pozzolana blends, followed by burning at low temperatures not exceeding 750 °C. Therefore, the technology of producing belite cement is one of the promising solutions to the problem of the cement industry’s consumption of energy resources and environmental pollution.

The production of conventional Portland cement is extremely carbon-intensive, accounting for approximately 8% of global CO₂ emissions (approximately one ton of CO₂ per ton of calcined limestone). In contrast, sustainable construction requires new binders with much lower embedded carbon content. Low-temperature billet cements (rich in β-Ca₂SiO₄) meet this need: they can be produced at only 600–900 °C via hydrothermal methods, rather than being fired at 1400–1450 °C as in OPC⁷. Because billet cement uses less calcium carbonate, it emits less CO₂, and the lower firing rate consumes less fuel⁸. This makes it promising for green building applications where energy efficiency and a reduced carbon footprint are critical. This study relies on hydrothermal processing of a mixture of lime, basalt, and glass waste to produce this type of cement at low temperatures. Basaltic volcanic ash is a naturally abundant pozzolanic material (providing reactive aluminosilicates), while recycled glass provides fine amorphous sodium silicates. When mixed with lime and heat-treated, these materials react to form hydrated calcium silicate phases (such as helibrandite). Calcination at low temperatures (≈ 600 °C) then converts these raw materials into β-C₂S belite⁹. The glass component acts as a flux, lowering the reaction temperature required for calcination, and acts as a pozzolana, generating more CSH cations during hydration, thereby thickening the cement matrix. The end result is a belite-rich cementitious powder that recycles waste and requires less combustion energy and less calcium carbonate than OPC.

Basalt volcanic ash in Saudi Arabia originates from the volcanic activity that occurred in the region¹⁰. The Arabian Peninsula, including parts of Saudi Arabia, has a geological history marked by volcanic activity¹¹. The most notable volcanic activity in Saudi Arabia occurred in the Quaternary period¹². The Harrat regions have contributed to the presence of basaltic materials, including volcanic ash¹³. Basalt volcanic ash is a gray to black rock, due to its significant content of Fe₂O₃ and FeO. Basalt volcanic ash primarily consists of SiO₂ usually less than 60% making it more basic and Al₂O₃ typically found in moderate amounts. In addition to MgO, CaO and other trace oxides like K₂O, Na₂O, and MnO₂ may also be present^14,15. Basalt ash tends to be durable and resistant to erosion, which can be advantageous for construction applications^16,17. Common uses of basalt volcanic ash include addition in concrete production as a pozzolana^18,19 and road construction as an asphalt mixture²⁰. Basalt volcanic ash is commonly used for soil amendment in agriculture to improve soil fertility²¹ as well as for erosion control measures²². Basalt volcanic ash is also commonly used for water filtration in water purification systems²³. Basalt ash is used for the manufacture of ceramic bricks and tiles^24,25.

The composition of waste glass varies depending on the type of glass²⁶. Container and flat glass used for bottles and mirrors respectively are typically soda-lime-silica glass made from silica sand, soda ash, and limestone. Recycling of glass involves the processes of collection, sorting, cleaning, crushing, melting, forming, and cooling²⁷. The benefits of recycling glass include; resource conservation, energy savings, reducing the environmental impact, and economic benefits²⁸. In contrast, recycling glass faces many challenges such as; contamination of the recycling stream making it harder to process, transportation costs, and fluctuating market demand affecting the economic viability of recycling²⁹. Using waste glass as a cement additive is an innovative approach that can provide both environmental and economic benefits³⁰. The benefits of using waste glass as a cement additive are reducing waste disposal, raw material conservation³¹and lowering energy requirements in cement production to reduce carbon emissions³².

Many studies have been conducted on the preparation of belite cement, and few studies have been conducted on measuring the properties of belite cement. The process involves hydrothermal preparation of the CSH with a Ca: Si ratio of 2:1 followed by calcination to produce the β-Ca₂SiO₄ phase. The effect of various synthesis conditions was investigated³³. Low-temperature synthesis of belite from a mixture of lime, BaCl₂, and different siliceous raw materials with the ratio (Ca + Ba)/Si = 2 was performed through hydrothermal treatment at 180 °C for 5 h and calcination at 750˚C for 3 h⁹. Low-temperature synthesis of belite from lime and white sand (Ca/Si = 2) in NaOH solution was done by hydrothermal treatment at 135 °C for 3 h followed by calcination at 1000 °C for 3 h³⁴. The hydration of plain belite cement was accelerated in the case of OPC blended belite cement³⁵. Belite cement was synthesized from lime and fly ash by hydrothermal treatment at 97 °C followed by ignition up to 1000 °C and blending belite cement with OPC increased the strength³⁶. In case of fly ash, lime, and NaOH mix with a ratio of 70:30:1 hydrothermally processed at 90–100 ◦C for 12 h and calcined at 800 °C for 1.5 h, the rate of early hydration heat release of belite cement was higher than that of OPC as well as the compressive strength improved with the addition of gypsum⁵.

The present research contribution aims to understand the hydration characteristics of belite cement prepared by hydrothermal treatment of mixes containing 20–35% lime at 190 °C for 3.5 h followed by calcination at 600 °C for 3 h. The heat of hydration and hydration characteristics of plain belite cement, belite/OPC blended cement, and volcanic ash/OPC blended cement hydrated in water for up to 28 days, were traced by combined water, compressive strength, bulk density, and total porosity measurements as well as proved by XRD, FTIR, TGA/DrTGA and SEM techniques.

Materials and experimental procedures

Raw materials and preparation of belite cements

The basaltic volcanic ash is basalt scoria from cinder cones located 130 km south of Medina, Kingdom of Saudi Arabia. The waste glass was obtained from a glass manufacturing workshop. The volcanic ash and waste glass were ground by a ball mill for 30 min. Lime was prepared by calcination of limestone at 950 °C for 3 h in a muffle furnace. The volcanic ash, glass, and lime were sieved to pass 125-micron sieve. Belite cement mixes illustrated in Table 1 were prepared by homogenizing powder of volcanic ash, glass, and lime and BaCl₂·2H₂O corresponding to 2 wt% Ba, manually in a plastic bag. Figure 1 illustrates the cement preparation, hydration, and testing processes. About 150 g of the raw mix was mixed with 750 ml distilled water (solid/liquid ratio = 1/5) in a stainless-steel capsule and was tightly closed. The hydrothermal treatment was carried out in an electric drier at 190 °C for 3.5 h. The specific values of the treatment temperature and duration were chosen based on previous research experience to ensure formation of the belite cement. Then, the capsule was cooled to room temperature. The product was filtered using filter paper in a porcelain funnel connected to an electric pump and dried in the microwave for 15 min. Then the product was ignited at 600 °C for 3 h in a muffle furnace. Three categories of belite cement were prepared to study the heat of hydration, hydration characteristics, mechanical properties, and microstructure. Their compositions are shown in Table 2. The first category is the plain belite cement which were symbolized H20-H35. The second category is belite/OPC blended cement prepared by mixing 50 wt% belite cement with 50 wt% OPC, and were symbolized HC20-HC35 respectively. The third category is volcanic ash/OPC blended cement, prepared by mixing 50 wt% volcanic ash with 50 wt% OPC, and was symbolized VAC50. Cement mixes were thoroughly mixed in plastic bags.

Table 1. Mix composition of Belite cement hydrothermal treatment and calcination.

Mix	Raw materials, wt/wt %
	Volcanic Ash	Glass	Lime
H20	50	30	20
H25	45	30	25
H30	40	30	30
H35	35	30	35

Fig. 1 [Images not available. See PDF.]

Cement preparation, hydration and testing processes, where [CS (compressive strength), CW (combined water), BD (bulk density), and TP (total porosity)].

Table 2. Mix composition of plain Belite cement, Belite/OPC blended cements and volcanic ash/opc blended cements.

Mix	Components, wt/wt %			w/c ratio
	Belite cement	VA	OPC
H20	100	0	0	0.45
H25	100	0	0	0.60
H30	100	0	0	0.65
H35	100	0	0	0.80
HC20	50	0	50	0.30
HC25	50	0	50	0.38
HC30	50	0	50	0.47
HC35	50	0	50	0.53
VAC50	0	50	50	0.30

Table 3 illustrates the chemical analysis of OPC, lime, volcanic ash, and glass by XRF. Lime is composed of CaO (93.23 wt%) and small amounts of SiO₂, MgO, and Al₂O₃. On the other hand, the main constituents of volcanic ash are SiO₂, Al₂O₃, Fe₂O₃, and CaO.

Table 3. Chemical composition of raw materials by XRF.

Oxide, wt%	Raw materials
	Lime	Volcanic ash	OPC
SiO2	1.92	60.92	22.13
Al2O3	0.65	14.73	4.13
Fe2O3	0.34	7.12	1.88
CaO	93.23	5.08	64.10
MgO	0.69	1.92	3.15
Na2O	0.20	4.23	0.13
K2O	0.04	2.41	0.62
P2O5	0.05	0.31	0.22
TiO2	0.05	0.80	0.06
SO3	0.48	0.17	2.16
Cl−	0.05	0.04	0.06
LOI*	1.55	2.12	1.16
Total	99.25	99.85	99.80

*LOI loss on ignition.

Testing of cement pastes

Performance of cement was assessed by measuring the initial heat of hydration as follows. 70 mL of distilled water whose temperature was maintained at 20 ± 0.5 ℃ (to), was injected into a thermally insulated container provided with an agitator rotating at 300 ± 50 rpm. 70 g of cement powder was immediately added to the water and the time counting was started. The temperature was recorded every 20 s, until the temperature reached a maximum value (Tmax), then started to decrease. The initial heat of hydration (Q) is calculated from the expression (Q = M.C.ΔT) expressed in kJ/kg. Where M is the total mass of cement powder and water (140 g), C is the heat capacity of water (4.18 Jg^-1°C^-1), and, ΔT is the temperature difference (ΔT = Tmax-to, °C)³⁷.

Cement pastes were prepared by mixing appropriate w/c ratios that produce workable cement paste, molded in a 2 × 2 × 2 cm³ iron mold, and stored in a humid atmosphere for 24 h, removed from molds, and, cured in water until testing at 3, 7, and 28 days. The bulk density of cement pastes was determined by Archimedes’ principle of buoyancy based on ASTM specification³⁸. The compressive strength of cement paste cubes was measured by a compressive strength apparatus based on ASTM specifications³⁹. The hydrated cement specimens were dried and free water content was determined by heating in a domestic microwave oven based on ASTM specifications⁴⁰. The chemically combined water content was determined for dried specimens by heating in a muffle furnace based on ASTM specifications⁴¹. The total porosity was estimated from the free and total water contents and bulk density according to following reference⁴². A set of three samples was used to estimate the hydration characteristics of cement pastes at curing ages. The average standard deviation was calculated for each measurement. The error bars were included in the graphs as well as the results were interpreted to reflect data variability. The oxide content of volcanic ash, glass, and lime was estimated by XRF Philips spectrometer PW1606. The mineral composition of raw materials and hydrated cement specimens was investigated by XRD Philips diffractometer PW1370 with nickel filter CuKα radiation source. FTIR was analyzed using a Perkin Elmer System Spectrum X spectrometer within the range 400–4000 cm^-1. TGA/DrTGA were performed using a Shimadzu corporation thermal analyzer (DTG-60 H), under a heating rate of 20 °C/min up to 900 °C, in nitrogen atmosphere. SEM analysed by JSM-IT200 model, Jeol, Japan, Central Laboratory for Microanalysis and Nanotechnology, Minia University.

Figure 2a shows the XRD patterns of raw materials. Glass is composed of amorphous sodium and calcium silicates as its characteristic broad bump appears in the between 10 and 38 2theta. Volcanic ash consists of amorphous silicates in addition to albite as its characteristic peaks appear at 17.3 and 28.3 2theta. Lime consists of calcium oxide, as its characteristic peaks appear at 17.3 and 28.3 2theta. In addition to portlandite, its characteristic peaks appear at 17.3 and 28.3 2theta due to hydration by moisture. OPC contains the clinker minerals alite, belite, aluminate, and ferrite in addition to calcite and gypsum⁴³. Figure 2b shows the FTIR spectra of raw materials. The FTIR of glass shows the following absorption bands. The broadband at 1013 cm⁻¹ is regarded as the Si–O–Si asymmetric stretching vibration of silica networks. The broadband around 3400 cm⁻¹ is regarded as the Si–OH stretching vibration of absorbed water. The sharp band at 768 cm⁻¹ is regarded as the Si–O–Si symmetric stretching vibration of well-ordered silica frameworks. The sharp band at 456 cm⁻¹ is regarded as the Si–O bending vibration of the silica matrix⁴⁴.

Fig. 2 [Images not available. See PDF.]

(a) XRD patterns and (b) FTIR spectra of raw materials.

The FTIR of volcanic ash shows the following absorption bands. The broadband at 1010 cm⁻¹ is regarded as the Si–O–Si asymmetric stretching vibration of silica networks. The broadband around 3400 cm⁻¹ is regarded as the Si–OH stretching vibration of absorbed water. The sharp band at 560 cm⁻¹ is regarded as the Fe–O stretching vibration of iron oxides. The sharp band at 455 cm⁻¹ is regarded as the Mg–O and Ca–O stretching vibration of magnesium or calcium oxides⁴⁵. The FTIR of lime shows the following absorption bands. The intense sharp band at 3635 cm⁻¹ is regarded as the O–H stretching vibration of hydroxyl groups indicating portlandite. The broadband around 1405 cm⁻¹ is regarded as the C–O asymmetric stretching vibration of carbonate groups indicating carbonation of lime. The sharp band at 897 cm⁻¹ regarded as the C–O out-of-plane bending vibration of carbonate groups. The broadband at 415 cm⁻¹ is regarded as the Ca–O stretching vibration of lime CaO⁴⁶.

The FTIR of OPC shows the following absorption bands. The very weak sharp band at 3640 cm^− 1 is regarded as the O–H stretching vibration of portlandite. The weak broadband at 3428 cm^− 1 is regarded as the Si–OH stretching vibration of absorbed water. The sharp band at 1411 cm^− 1 is regarded as the C–O asymmetric stretching vibration of carbonate of limestone blended with OPC. The weak sharp band at 1144 cm^− 1 is regarded as the S–O stretching vibration of sulfate of gypsum added to OPC. The weak sharp band at 1087 cm^− 1 and sharp broadband at 906 cm^− 1 are regarded to Si–O–Si asymmetric and symmetric stretching vibrations respectively of calcium silicate phases C₃S and C₂S. The sharp band at 900 cm^− 1 is regarded as the C–O out-of-plane bending vibration of carbonate of limestone blended with OPC. The sharp band at 511 cm^− 1 is regarded as the Al–O and Si–O bending vibration of aluminate as well as silicate networks, The sharp band at 421 cm^− 1 is regarded as the Ca–O stretching vibration of calcium-related phases (C₃A, C₄AF, Portlandite)⁴⁷. The SEM imaging gives an approximate idea of ​​the grain size distribution and crystallization nature of the raw materials.

Figure 3 shows the SEM images of raw materials. In terms of the grain size of the raw materials, it is clear that the glass particles are finer than the volcanic ash particles, although the glass contains a percentage of coarse particles with a diameter exceeding 50 microns. While lime is very fine, as its particles do not exceed 3 microns in diameter. In terms of the nature of crystallization, it is clear that the lime and OPC particles are more regular, which expresses the crystallization of their minerals, while the volcanic ash and glass particles do not form in specific crystalline patterns, which indicates the prevailing amorphous state of the volcanic ash and glass.

Fig. 3 [Images not available. See PDF.]

SEM images of raw materials.

Results and discussion

Performance of cement by initial heat of hydration

The initial heat of hydration measurement (Fig. 4) illustrates the performance of prepared belite cement compared to the reference value for heat of hydration (85–100 kJ/kg initial stage heat of hydration for OPC), showing which mixes exceed or stay below this threshold⁴⁸. The VAC50 mix shows the lowest heat of hydration among all the mixes, indicating a slower reaction and reduced heat generation, as well as its suitability for massive concrete structures where heat control is critical to avoid thermal cracking⁴⁹. H20–H35 mixes, which represent belite cement with increasing lime content (20–35%), exhibit the highest heat of hydration compared to all cement mixes⁵⁰. The heat of hydration increases progressively as the lime content due to the exothermic hydration reaction of lime, releasing more heat⁴⁸. Accordingly, these belite cements could not be suitable for massive concrete structure applications due to their high heat generation⁴⁹. HC20–HC35 mixes (belite cement blended with 50% OPC) exhibit a moderate heat of hydration compared to the pure belite cements (H20–H35), due to the dilution effect of OPC, which hydrates more rapidly and releases lower heat of hydration⁵⁰. These mixes are suitable for applications requiring moderate heat of hydration and low initial strength gain⁴⁸.

Fig. 4 [Images not available. See PDF.]

Heat of hydration of cements, kJ/kg.

Phase identification of cement pastes

X-ray diffraction

Figure 5a shows the XRD patterns of H20 untreated, hydrothermally treated, calcined, and hydrated at 3 days. When H20 was hydrothermally treated at 190 °C, the amorphous helibrandite phase was formed as appearing in the broad bump between 10 and 38 2theta⁹. The formation of helibrandite results from the reaction of a part of the amorphous silicates of the volcanic ash with lime during the hydrothermal treatment. When the product of the H20 mixture (hydrothermally treated at 190 °C) was calcined at 600 °C, the helibrandite was transformed into belite, which showed their characteristic peaks at 32–33, 39, 45.6 and 46.5 2theta⁵¹. Indeed, all peaks in the 29–32°2θ region can be attributed to β-C₂S (belite); not to C₃S (alite) (especially with the uncertainty of the presence of the characteristic 32.2° or 31.4°2θ peaks). Even if alite was marginally metastable below its equilibrium temperature, the solid-state diffusion rate at 600 °C is order of magnitude too slow to organize Ca²⁺ and SiO₄⁴⁻ into the alite crystal structure within the calcination period (3 h). Hence, most literature reports show negligible C₃S formation below 1000°C⁵². When the product of the H20 mixture (hydrothermally treated at 190 °C and calcined at 600 °C) was hydrated in water, the percentage of portlandite formation did not increase, and the percentage of belite was only slightly reduced, which will negatively affect the mechanical properties of the produced cement. Figure 5b shows the XRD patterns of H20 calcined and hydrated at 3–28 days. When the H20 mixture (hydrothermally treated at 190 °C and calcined at 600 °C) was hydrated in water for longer periods, the rate of hydration of belite increased. The amorphous hydrated products (CSH) were formed giving a wide bump at 10–38 2theta. This may lead to an improvement in the mechanical properties of the produced cement, confirming that the produced cement hydrates slowly. It is expected to give higher mechanical properties at later ages due to its richness in belite. Figure 5c shows H20-H35 hydrated at 28 days. With the increasing amount of lime, the rate of CSH formation improves, as seen from the increase in the intensity of the amorphous phases (wide bump at 10–38 2theta), up to the mixture containing 25% lime. Then the rate of CSH formation decreases at higher lime ratios. The same behavior can be explained by following the increase of portlandite.

Fig. 5 [Images not available. See PDF.]

XRD patterns of (a) H20 untreated, hydrothermally treated, calcined and hydrated at 3 days, (b) H20 calcined and hydrated at 3–28 days, (c) H20-H35 hydrated at 28 days, (d) HC20 calcined and hydrated at 3–28 days, (e) HC20-HC35 hydrated at 28 days as well as (f) VAC50 unhydrated and hydrated up to 28 days.

Figure 5d shows the XRD pattern of HC20 calcined and hydrated at 3–28 days. When H20 was mixed with OPC and hydrated in water for 28 days, the alite and belite phases originating from the OPC were observed to hydrate at a faster rate than the belite phase originating from the produced belite cement. It is also observed that the rate of formation of amorphous CSH increased with the age of hydration. Figure 5e shows the XRD pattern of HC20-HC35 hydrated at 28 days. When samples H20-H35 were mixed with OPC and hydrated in water for 28 days, an improvement in the rate of hydration was observed. This was indicated by the increase in the rate of CSH and portlandite formation from mixture H20 to mixture H30, then the rate of hydration decreased in mixture H35. This may prove that the rate of hydration of the produced belite cement increased in the presence of OPC⁵³. Figure 5f shows the XRD pattern VAC50 unhydrated and hydrated for up to 28 days. When volcanic ash was mixed with OPC and hydrated for 28 days, an improvement in the rate of hydration was observed. This was indicated by the increase in the rate of portlandite formation until the age of 7 days. Then a significant decrease in the rate of portlandite formation was observed after that, accompanied by an increase in the rate of CSH formation. This was indicated by the increase in the intensity of the wide bump from 10 to 38 2theta. This indicates the reaction of portlandite with amorphous silica in the volcanic ash to form CSH, confirming the pozzolanic role of the volcanic ash⁵⁴.

FTIR analysis

Figure 6a shows the FTIR spectra of H20 untreated, hydrothermally treated, calcined, and hydrated at 3 days. After the hydrothermal treatment of H20, the intensity of the sharp band at 3635 cm⁻¹ s regarded as the O–H stretching vibration of hydroxyl groups linked to portlandite, decreased due to the reaction of portlandite with amorphous silica forming hydrated calcium silicates. At the same time, the broadband at 1032 cm⁻¹ is regarded as the Si–O–Si asymmetric stretching vibration of silica networks shifted to 973 confirming the formation of hydrated calcium silicates. The intensity of the broadband around 3400 cm⁻¹ is regarded as the Si–OH stretching vibration of absorbed water increases due to the inclusion of high-water content in hydrated calcium silicates. After calcination of the hydrothermally treated H20, the formation of dicalcium silicate C₂S is proved from the appearance of new absorption bands at 996 and 510 cm⁻¹ which are regarded as the Si–O–Si asymmetric and symmetric stretching vibrations as well as Ca–O stretching / Si–O bending vibrations of Ca–O and Si–O bonds in C₂S respectively. After hydration of calcined hydrothermally treated H20, the formation of CSH is elucidated from the appearance of the new absorption band at 928 cm-1 that is regarded as the Si–OH stretching vibration of CSH⁵⁵. Figure 6b shows the FTIR spectra of H20 calcined and hydrated at 3–28 days. The broadening of the asymmetric stretching vibration band of Si-O bond of CSH at 967 cm-1 with aging of belite cement, (H20-H35) hydrothermally treated, calcined, and hydrated at 28 days, is regarded to the increasing the degree of polymerization forming longer silicate chains and a more complex network, increasing cross-linking of silicate chains, and, replacement of Si by Ca or the incorporation of other ions (such as Ba2 + ions) in CSH structure⁵⁶. Figure 6c shows the FTIR spectra of H20-H35 hydrated at 28 days. The intensity of the asymmetric stretching vibration band of the Si-O bond of CSH at 967 cm⁻¹ decreases with increasing lime content of belite cement, (from H20 to H35). This is due to lowering the formation of CSH with decreasing volcanic ash content.

Figure 6d shows the FTIR spectra of (a) HC20 calcined and hydrated at 3–28 days. The intensity and broadening of the asymmetric stretching vibration band of the Si-O bond of CSH at 967 cm-1 increases with the aging of HC20 up to 28 days, due to the formation of CSH regarding the hydration of OPC. Figure 6e, shows the FTIR spectra of HC20-HC35 hydrated at 28 days. The broadening of the asymmetric stretching vibration band of the Si-O bond of CSH at 967 cm-1 increases from HC20 to HC25 and then decreases up to HC35. This indicates that increasing lime content in the belite cement adversely influences the hydration of OPC. In Fig. 6f shows the FTIR spectra of VAC50 unhydrated and hydrated up to 28 days. The intensity of the sharp stretching vibration band of portlandite at 3635 cm⁻¹ does not significantly decrease with the aging of volcanic ash/OPC blended cement (VAC50) up to 28 days. This is due to the limited pozzolanic activity of volcanic ash.

Fig. 6 [Images not available. See PDF.]

FTIR spectra of (a) H20 untreated, hydrothermally treated, calcined and hydrated at 3 days, (b) H20 calcined and hydrated at 3-28 days, (c) H20-H35 hydrated at 28 days, (d) HC20 calcined and hydrated at 3-28 days, (e) HC20-HC35 hydrated at 28 days as well as (f) VAC50 unhydrated and hydrated up to 28 days.

TG analysis

Figure 7a shows the TGA/Dr.TGA thermogram of H20 mixture hydrothermally treated at 190 °C. The sharp peak around 460 °C indicates that the belite cement undergoes a significant change in weight at that temperature due to rapid dehydration of the residual portlandite. The broad peaks around 60 °C (extending beyond 200 °C), 650 °C, and 820 °C indicate the gradual slow decomposition processes regarding; loss of free absorbed water, decomposition of hillebrandite into belite, and phase transformation of belite respectively⁵⁷. Figure 7b–d shows the TGA/DrTGA patterns of H20 hydrated at 3–28 days. The results of the derivative weight corresponding to the dehydration of the belite phase show a gradual increase in the content of the CSH with the age of the hydration up to 28 days. However, the decrease in the values of the derivative weight corresponding to the dehydration of the portlandite phase, as well as the slight increase in the percentage of total weight loss with the age of the hydration, indicate a decrease in the rate of hydration of the belite cement. The derivative weight corresponding to the dehydration of the belite phase shows an increase in the formation of CSH as the percentage of lime added to the composition of the beite cement increases. However, the increase in the percentage of total weight loss shows that the percentage of 30% lime corresponds to the highest percentage of weight loss with the hydration of cement, then the percentage of total weight loss decreases when the percentage of lime increases to 35%. Figure 7e–h shows TGA/DrTGA patterns of H20-H35 hydrated at 28 days. The values of the derivative weight corresponding to the dehydration of the portlandite phase of belite/OPC blended cement are within 3–4 times the values corresponding to the pure belite cement, and their values of the percentage of total weight loss are about twice the values of the pure belite cement. This confirms the improvement in the hydration of belite cement in the presence of OPC. Figure 8a–c shows the TGA/DrTGA patterns of HC20 hydrated at 3–28 days, Fig. 8d–g shows the TGA/DrTGA patterns of HC20-HC35 hydrated at 28 days, and Fig. 9a–c shows the TGA/DrTGA patterns of VAC50 hydrated at 3–28 days. The values of the derived weight corresponding to the dehydration of the portlandite phase, as well as the values of the total weight loss ratios of the volcanic ash/OPC blended cement, are higher than those of pure belite cement, but lower than those of the OPC blended with belite cement. This confirms that the rate of hydration of the belite/OPC blended cement is higher than that of the volcanic ash/OPC blended cement. This is evident from comparing the TGA/DrTGA patterns of H20, HC20, and VAC50 hydrated at 28 days.

Fig. 7 [Images not available. See PDF.]

TGA/DrTGA patterns of (a) H20 hydrothermally treated, (b–d) H20 hydrated at 3–28 days as well as (e–h) H20-H35 hydrated at 28 days.

Fig. 8 [Images not available. See PDF.]

TGA/DrTGA patterns of (a–c) HC20 hydrated at 3–28 days as well as (d–g) HC20-HC35 hydrated at 28 days.

SEM analysis

Figure 10 show the SEM images of H20 hydrothermally treated at 190 °C, calcined at 600 °C and, hydrated in water for up to 28 days. The hydrothermal treatment of the H20 resulted in the volcanic ash and glass particles being coated with a fibrous amorphous material resulting from the formation of hydrated calcium silicates. This fibrous amorphous material was transformed into dispersed nanoparticles after firing at 600 °C due to the loss of water of crystallization, and then it was transformed into an amorphous material after hydrolysis due to the formation of amorphous calcium silicates. The amount of amorphous material increases with the age of the hydrated sample. Although both the amount of amorphous material and the percentage of combined water increase with the increase in the percentage of added lime, this pattern contradicts the results of compressive strength, bulk density, and total porosity, as both of them decrease with the increase in the percentage of added lime. It seems that the increase in the amount of amorphous material and the percentage of combined water increases with the increase in the percentage of added lime due to the hydration of lime into calcium hydroxide and not because of the hydration of calcium silicates. This explains the nature of the decrease in compressive strength and density and the increase in porosity with the increase in the percentage of added lime⁵⁸although the percentage of combined water increases.

Fig. 9 [Images not available. See PDF.]

TGA/DrTGA patterns of VAC50 hydrated at 3–28 days.

Fig. 10 [Images not available. See PDF.]

SEM images of H20 hydrothermally treated at 190 °C for 3 h, calcined at 600 °C for 3 h and hydrated in water for up to 28 days.

Figure 11 shows the SEM images of belite cement H20, OPC blended with H20 and, OPC blended with volcanic ash hydrated in water for 28 days. SEM images of the hydrated cement samples confirm the XRD and TGA results that the rate of hydration of belite/OPC blended cement is the highest, followed by volcanic ash/OPC blended cement, and in last place comes pure belite cement. This is clearly shown by observing the accumulation of non-hydrated crystalline cementitious materials in the belite cement sample. While the belite/OPC blended cement is rich in amorphous hydration products. Figure 12 shows the SEM images of belite cement H20-H35 and OPC blended with H20-H35 hydrated in water for 28 days. The density of the amorphous CSH increases with the percentage of lime added to the composition of the belite cement up to 30% lime, and then decreases in the belite cement containing 35% lime, and these results are consistent with the XRD and TGA results. At the same time, the density of the amorphous CSH increases with the addition of OPC to the composition of the belite cement. This proves that the addition of OPC enhances the hydration of belite cement.

Fig. 11 [Images not available. See PDF.]

SEM images of (a) belite cement H20, (b) OPC blended with H20 and (c) OPC blended with volcanic ash hydrated in water for 28 days.

Physico-mechanical properties of cement pastes

Figure 13a shows the combined water content of pure belite cement, belite/OPC blended cement, and volcanic ash/OPC blended cement hydrated in water for 28 days. The results of the combined water content are consistent with the compressive strength measurements, showing that belite/OPC blended cement, as well as those blended with volcanic ash, contain a higher combined water content than pure plain belite cement. This is due to the slower hydration of the belite phase. However, the combined water content increases with increasing lime percentage added to belite cement blends, from H20 to H35, as well as in belite/OPC blended cement. This is due to the abundance of hydrated lime remaining after reacting with silica to form belite. The curve illustrates the influence both of lime content and more reactive phases (OPC or pozzolans) on the rate and extent of hydration. The belite cements (H20-H35) Favor a lower but steadier hydration profile, while OPC blended belite cements (HC20-HC35) ensures a strong early contribution to combined water content and further growth over time.

Fig. 12 [Images not available. See PDF.]

SEM images of (a) belite cements H20-H35 and (b) OPC blended with H20-H35 hydrated in water at 28 days.

Figure 13b,c show the bulk density and total porosity of pure belite cement, belite/OPC blended cement, and volcanic ash/OPC blended cement hydrated in water for 28 days. Although, the variation in density and porosity of H20-H35 is not monotonous, the bulk density decreases and total porosity increases moving from volcanic ash/OPC blended cement, to belite/OPC blended cement, and finally to plain belite cement. This confirms the weak hydration of belite cement, which leads to more free water remaining, which leads to a decrease in bulk density and an increase in total porosity. Figure 13d shows the compressive strength of pure belite cement, belite/OPC blended cement, and volcanic ash/OPC blended cement hydrated in water for 28 days. The compressive strength of all plain belite cement; H20-H35 is low. The compressive strength gained with the age of hydration is also low. H20 has a lower compressive strength than mixes of other plain belite cements; H25 to H35 at early ages, while it has a higher compressive strength than the other belite cements at later ages. All belite/OPC blended cement; HC20 to HC35 have improved compressive strength compared with plain belite cements, among which, HC20 shows the highest compressive strength at all ages of hydration. While volcanic ash/OPC blended cement has a compressive strength on average between that of plain belite cement (H20 to H35) and belite/OPC blended cement.

Fig. 13 [Images not available. See PDF.]

(a) combined water content, (b) bulk density, (c) total porosity, and (d) compressive strength of pure belite cement, Portland cement blended with belite cement, and blended with volcanic ash hydrated in water for 28 days.

The variability in measurements of total porosity and compressive strength is greater than for other properties. This typically results from an uneven pore structure—caused by variations in pore distribution during casting and curing—which produces areas of both high and low porosity. Since high porosity reduces strength, the overall range of values becomes larger.

Conclusions

Based on the above research findings, the following points were concluded. Volcanic ash contains coarse amorphous silicates and albite. Hydrated dicalcium silicate, (helibrandite) is formed via the hydrothermal treatment, then transformed into belite by calcination at 600 °C. The plain belite cement was slowly hydrated in water giving low mechanical properties. It is expected to provide higher mechanical properties at later ages due to its richness in belite. The rate of hydration improves both by increasing the content of lime to 25–30% and by blending with OPC. The volcanic ash has low pozzolanic properties. Belite/OPC and volcanic ash/OPC blended cement contain a higher combined water content than pure plain belite cement. The bulk density and total porosity results confirm the slow hydration of belite cement. The compressive strength of all plain belite cement (H20-H35) is low. The compressive strength gained with the age of hydration is also low. All belite blended cement have improved compressive strength, among which HC20 shows the highest compressive strength ​​at all ages of hydration. Plain belite cement, releases a high heat of hydration. Whereas belite/OPC blended cement releases a lower heat of hydration. This makes it more suitable for applications where moderate heat of hydration and low initial strength gain are not harmful.

Acknowledgements

This work was funded by the Deanship of Graduate Studies and Scientific Research at Jouf University under grant No. (DGSSR-2023-02-02284).

Author contributions

Tamer H.A. Hasanin: Manuscript proposal, Result drawing, Assist in discussion, Manuscript editing, Language editing, Literature review collection. Alaa M. Alsirhani: Manuscript revision, Funding. Mahmoud A.A. Ibrahim: Manuscript revision, Responding to reviewers’ comments, Funding. Yogesh K. Ahlawat: Language editing. M.A. Tantawy: Manuscript proposal, Experimental work, Result drawing, Discussion of results, Language editing, Manuscript preparation.

Data availability

The authors confirm that the data that support the findings of this study are available from the corresponding author upon reasonable request.

Declarations

Competing interests

The authors declare no competing interests.

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

References

1. Liu, J; Zhang, S; Wagner, F. Exploring the driving forces of energy consumption and environmental pollution in china’s cement industry at the provincial level. J. Clean. Prod.; 2018; 184, pp. 274-285. [DOI: https://dx.doi.org/10.1016/j.jclepro.2018.02.277] 1:CAS:528:DC%2BC1cXktlSmurw%3D

2. Bildirici, ME; Ersin, ÖÖ. Cement production and CO₂ emission cycles in the USA: evidence from MS-ARDL and MS-VARDL causality methods with century-long data. Environ. Sci. Pollut Res. Int.; 2024; 31, 24 pp. 35369-35395. [DOI: https://dx.doi.org/10.1007/s11356-024-33489-2] [PubMed: https://www.ncbi.nlm.nih.gov/pubmed/38724851][PubMedCentral: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11541327]

3. Li, C; Wu, M; Yao, W. Eco-efficient cementitious system consisting of Belite-Ye’elimite-Ferrite cement, limestone filler, and silica fume. ACS Sustainable Chem. Eng.; 2019; 7, 8 pp. 7941-7950. [DOI: https://dx.doi.org/10.1021/acssuschemeng.9b00702] 1:CAS:528:DC%2BC1MXlslGmt7w%3D

4. Tantawy, M. A., Shatat, M. R., El-Roudi, A. M., Taher, M. A. & Abd-El-Hamed, M. Low temperature synthesis of Belite cement based on silica fume and lime. Int. Sch. Res. Notices. 873215https://doi.org/10.1155/2014/873215 (2014).

5. Gong, Y; Liu, C; Chen, Y. Properties and mechanism of hydration of fly Ash Belite cement prepared from Low-Quality fly Ash. Appl. Sci.; 2020; 10, 7026. [DOI: https://dx.doi.org/10.3390/app10207026] 1:CAS:528:DC%2BB3cXisVSju7zJ

6. Rungchet, A; Chindaprasirt, P; Wansom, S; Pimraksa, K. Hydrothermal synthesis of calcium. Sulfoaluminate-Belite cement from industrial waste materials. J. Clean. Prod.; 2016; 115, pp. 273-283.1:CAS:528:DC%2BC28XitFSmtA%3D%3D

7. Bekerė, K; Malaiškienė, J; Škamat, J. An analysis of a cement hydration process using glass waste from household appliances as a supplementary material. Processes; 2025; 13, 840. [DOI: https://dx.doi.org/10.3390/pr13030840] 1:CAS:528:DC%2BB2MXhtlWjurbI

8. Stevulova, N; Filkova, I; Baltakys, K. Low-temperature synthesis of Belite cement from reactive mixtures based on coal fly Ash. J. Civil Eng. Archit.; 2012; 6, pp. 190-196.

9. Tantawy, MA. Influence of silicate structure on the low temperature synthesis of Belite cement from different siliceous Raw materials. J. Mater. Sci. Chem. Eng.; 2015; 3, pp. 98-106. [DOI: https://dx.doi.org/10.4236/msce.2015.35011] 1:CAS:528:DC%2BC2MXht1Wgsr3E

10. Ali, S; Abdallah, SE; Abu Anbar, MM; Azzaz, SA; Alrashidi, KN. Petrology of continental, OIB-like, basaltic volcanism in Saudi arabia: constraints on cenozoic anorogenic mafic magmatism in the Arabian shield. Front. Earth Sci.; 2022; 10, 921994.2022FrEaS.10.1994A [DOI: https://dx.doi.org/10.3389/feart.2022.921994]

11. Sonbul, AR; Mesaed, AA. Petrographic characterization of the different types of basalts of Harrat al fatih, Ablah area, West central Arabian shield, Saudi Arabia. Open. J. Geo; 2017; 7, pp. 871-887.2017OJGeo..7.871S [DOI: https://dx.doi.org/10.4236/ojg.2017.76060] 1:CAS:528:DC%2BC1MXitF2kurw%3D

12. Abdel Wahab, A; Abul Maaty, MA; Stuart, FM; Awad, H; Kafafy, A. The geology and geochronology of al Wahbah Maar crater, Harrat kishb, Saudi arabia, quat. Geochronology; 2014; 21, pp. 70-76. [DOI: https://dx.doi.org/10.1016/j.quageo.2013.01.008]

13. Robinson, JE et al. Database for the geologic map of the Northern Harrat Rahat volcanic field, Kingdom of Saudi Arabia. U S Geol. Surv. Data Release; 2019; [DOI: https://dx.doi.org/10.5066/P9Q3WGTN]

14. Khan, K; Johari, MAM; Amin, MN; Nasir, M. Development and evaluation of basaltic volcanic Ash based high performance concrete incorporating metakaolin, micro and nano-silica. Develop Built Envir; 2024; 17, 100330. [DOI: https://dx.doi.org/10.1016/j.dibe.2024.100330]

15. Horwell, CJ; Fenoglio, I; Fubini, B. Iron-induced hydroxyl radical generation from basaltic volcanic Ash. Earth Planet. Sci. Lett.; 2007; 261, 30 pp. 3-4. [DOI: https://dx.doi.org/10.1016/j.epsl.2007.07.032] 1:CAS:528:DC%2BD2sXhtVCgt7rM

16. Wu, G; Wang, X; Wu, Z; Dong, Z. Durability of basalt fibers and composites in corrosive environments. J. Compos. Mater.; 2014; 49, 7 pp. 873-887. [DOI: https://dx.doi.org/10.1177/0021998314526628] 1:CAS:528:DC%2BC2MXltVCjtb4%3D

17. Zhang, Y et al. Sulfate resistance and degradation mechanism of basalt fiber modified graphite tailings cement-based materials. J. Mater. Res. Techn; 2023; 26, pp. 8757-8775. [DOI: https://dx.doi.org/10.1016/j.jmrt.2023.09.196] 1:CAS:528:DC%2BB3sXitVWiu7zI

18. Harzali, H; Zawrah, MF; Aldarhami, S; Tantawy, MA. Influence of granite on physico-chemical properties of volcanic Ash pozzolanic cement pastes. Construct Build. Mater.; 2024; 438, 9 137113. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2024.137113] 1:CAS:528:DC%2BB2cXhsVOmtL%2FL

19. Khan, K et al. Effect of fineness of basaltic volcanic Ash on pozzolanic reactivity, ASR expansion and drying shrinkage of blended cement mortars. Mater; 2019; 12, 16 2603. [DOI: https://dx.doi.org/10.3390/ma12162603] 1:CAS:528:DC%2BB3cXjvF2jt78%3D

20. Ibrahim, A; Faisal, S; Jamil, N. Use of basalt in asphalt concrete mixes. Construct Build. Mater.; 2009; 23, 1 pp. 498-506. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2007.10.026]

21. El-Desoky, AI; Hassan, AZA; Mahmoud, AM. Volcanic Ash as a material for soil conditioner and fertility. J. Soil. Sci. Agric. Eng. Mansoura Univ.; 2018; 9, 10 pp. 491-495.

22. Minasny, B; Fiantis, D; Hairiah, K; Van Noordwijk, M. Applying volcanic Ash to croplands – The untapped natural solution. Soil. Secur.; 2021; 3, 100006. [DOI: https://dx.doi.org/10.1016/j.soisec.2021.100006]

23. Alraddadi, S. Utilization of nano volcanic Ash as a natural economical adsorbent for removing cadmium from wastewater. Heliyon8(12). https://doi.org/10.1016/j.heliyon.2022.e12460 (2022). e12460.

24. Candamano, S; De Luca, P; Garofalo, P; Crea, F. Ceramic materials containing volcanic Ash and characterized by photoluminescent activity. Envir; 2023; 10, 10 172. [DOI: https://dx.doi.org/10.3390/environments10100172]

25. Serra, MF; Conconi, MS; Suarez, G; Aglietti, EF; Rendtorff, NM. Volcanic Ash as flux in clay based triaxial ceramic materials, effect of the firing temperature in phases and mechanical properties Ceram. Inter; 2015; 41, pp. 6169-6177. [DOI: https://dx.doi.org/10.1016/j.ceramint.2014.12.123] 1:CAS:528:DC%2BC2MXhs1Smsrc%3D

26. Hamed, H; Eldiasty, M; Sahebari, SMS; Abou-Ziki, JD. Applications, materials, and fabrication of micro glass parts and devices: an overview. Mater. Today; 2023; 66, pp. 194-220. [DOI: https://dx.doi.org/10.1016/j.mattod.2023.03.005]

27. Robert, D; Baez, E; Setunge, S. A new technology of transforming recycled glass waste to construction components. Construct Build. Mater.; 2021; 313, 27 125539. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2021.125539] 1:CAS:528:DC%2BB3MXis12hsL7P

28. Hamada, H; Alattar, A; Tayeh, B; Yahaya, F; Thomas, B. Effect of recycled waste glass on the properties of high-performance concrete: A critical review. Case Stud. Construct Mater.; 2022; 17, e01149. [DOI: https://dx.doi.org/10.1016/j.cscm.2022.e01149]

29. Bristogianni, T; Oikonomopoulou, F. Glass up-casting: a review on the current challenges in glass recycling and a novel approach for recycling as-is glass waste into volumetric glass components. Glass Struct. Eng.; 2023; 8, pp. 255-302. [DOI: https://dx.doi.org/10.1007/s40940-022-00206-9]

30. Shi, C; Zheng, K. A review on the use of waste glasses in the production of cement and concrete resources. Conserv. Recyc; 2007; 52, 2 pp. 234-247. [DOI: https://dx.doi.org/10.1016/j.resconrec.2007.01.013]

31. Paul, D; Bindhu, KR; Matos, AM; Delgado, J. Eco-friendly concrete with waste glass powder: A sustainable and circular solution. Construct Build. Mater.; 2022; 355, 14 129217. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2022.129217] 1:CAS:528:DC%2BB38XisFOlt7vM

32. Hassani, MS; Matos, JC; Zhang, Y; Teixeira, ER. Green concrete with glass powder-A literature review. Sust; 2023; 15, 20 14864. [DOI: https://dx.doi.org/10.3390/su152014864] 1:CAS:528:DC%2BB3sXitlSrsL7K

33. Dutta, N. & Chatterjee, A. Synthesis of dicalcium silicate based cement. 2nd Int. Conf. Civil Eng. Mater. Sci.IOP Conf. Series: Mater. Sci. Eng. 216(012027). https://doi.org/10.1088/1757-899X/216/1/012027 (2017).

34. Tantawy, MA. Low-temperature Preparation of β-C₂S from sand/lime mixture: influence of sodium hydroxide. Ann. Chem. Sci. Res.; 2019; 1, 2 000512. [DOI: https://dx.doi.org/10.31031/ACSR.2019.01.000512]

35. Maheswaran, S; Kalaiselvam, S; Palani, GS; Sasmal, S. Investigations on the early hydration properties of synthesized b-belites blended cement pastes. J. Therm. Anal. Calorim.; 2016; 1, pp. 53-64. [DOI: https://dx.doi.org/10.1007/s10973-016-5386-x] 1:CAS:528:DC%2BC28XksVSitLc%3D

36. Yongfan, G; Yonghao, F. Preparation of Belite cement from stockpiled high-carbon fly Ash using granule-hydrothermal synthesis method. Construct Build. Mater.; 2016; 111, pp. 175-181. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2016.02.043] 1:CAS:528:DC%2BC2sXntVyms7g%3D

37. Wangtaoying, X., Jihaihong, Z. & Zhangyao, B. Discussion on determination method of unslaked lime activity for dry flue gas desulfurization. E3S web Conf.136, 7018 ICBTE. https://doi.org/10.1051/e3sconf/201913607018 (2019).

38. ASTM C188-23, Standard test method for density of hydraulic cement. (2023).

39. ASTM C109-80, Standard test methods for compressive strength of hydraulic cements. (1983).

40. ASTM C1074-23, Standard practice for estimating concrete strength by maturity. (2023).

41. ASTM C114-23, Standard test methods for chemical analysis of hydraulic cement. (2023).

42. Chen, L; Wu, Y; Liu, Z. Determination of total porosity in cement pastes: A comprehensive study using free and total water content. Construct Build. Mater.; 2022; 331, 127350. [DOI: https://dx.doi.org/10.1016/j.conbuildmat.2022.127350] 1:CAS:528:DC%2BB38Xht12hu77O

43. Jadhav, R; Debnath, NC. Computation of X-ray powder diffractograms of cement components and its application to phase analysis and hydration performance of OPC cement. Bull. Mater. Sci.; 2011; 34, 5 pp. 1137-1150. [DOI: https://dx.doi.org/10.1007/s12034-011-0134-0] 1:CAS:528:DC%2BC38XjvVSmsbY%3D

44. Farouk, M et al. FTIR studies and optical absorption of zinc Borate glasses containing WO3. App Phys. A; 2020; 126, 9 696.2020ApPhA.126.696F [DOI: https://dx.doi.org/10.1007/s00339-020-03890-y] 1:CAS:528:DC%2BB3cXhs1Sjsb%2FO

45. Hasanah, M et al. Extraction and characterization of silicon dioxide from volcanic Ash of Mount sinabung, indonesia: A preliminary study. J. Eco Eng.; 2022; 23, 3 pp. 130-136. [DOI: https://dx.doi.org/10.12911/22998993/145479]

46. Pandey, S. & Sengupta, J. B. Fourier Transform Infrared Spectrescoby: A Tool for Detection of Liam Content in Hot Mix Asphalt, 26th ARRB Conf. Res(Driving Effic, 2014).

47. Springfield, T. Application of FTIR for quantification of alkali in cement, MSc. Thesis, Uuiversity of North Texas. (2011).

48. Aydin, AC; Kan, A; Fayetorbay, I; Öz, A. Hydration properties of Boron modified active Belite cement concrete. J. BAUN Inst. Sci. Technol.; 2018; 20, 2 pp. 282-292. [DOI: https://dx.doi.org/10.25092/baunfbed.430969]

49. Shirani, S et al. Influence of curing temperature on Belite cement hydration: A comparative study with Portland cement. Cem. Concrete Res.; 2021; 147, 106499. [DOI: https://dx.doi.org/10.1016/j.cemconres.2021.106499] 1:CAS:528:DC%2BB3MXht1ejtrvN

50. Morin, V. et al. Hydration of a belite-calcium sulfoaluminate-ferrite cement, Conference: 13th Int. Cong. Chem. Cement, Madrid, Spain, July (2011).

51. Sun, F; Pang, X; Wei, J; Zeng, J; Niu, J. Synthesis of alite, Belite and ferrite in both monophase and polyphase States and their hydration behavior. J. Maters Resear Tech.; 2023; 25, pp. 3901-3916. [DOI: https://dx.doi.org/10.1016/j.jmrt.2023.06.151] 1:CAS:528:DC%2BB3sXhtlGjsbfL

52. Taylor, H. F. W. Cement Chemistry (2nd ed.). ISBN 978-0727725929 (Thomas Telford Publishing, 1997).

53. Gong, Y; Yang, J; Sun, H; Xu, F. Effect of fly Ash Belite cement on hydration performance of Portland cement. Crystals; 2021; 11, 740. [DOI: https://dx.doi.org/10.3390/cryst11070740] 1:CAS:528:DC%2BB3MXisVWhurbJ

54. Khan, K et al. Effect of fineness and heat treatment on the pozzolanic activity of natural volcanic Ash for its utilization as supplementary cementitious materials. Crystals; 2022; 12, 302. [DOI: https://dx.doi.org/10.3390/cryst12020302] 1:CAS:528:DC%2BB38XlslOls7c%3D

55. Madadi, A; Wei, J. Characterization of calcium silicate hydrate gels with different calcium to silica ratios and polymer modifications. Gels; 2022; 8, 2 75. [DOI: https://dx.doi.org/10.3390/gels8020075] [PubMed: https://www.ncbi.nlm.nih.gov/pubmed/35200457][PubMedCentral: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8924764]1:CAS:528:DC%2BB38XmtVOrtLs%3D

56. Puertas, F; Goni, S; Hernandez, MS; Varga, C; Guerrero, A. Comparative study of accelerated decalcification process among C3S, grey and white cement pastes. Cem. Concrete Compos.; 2012; 35, pp. 384-391. [DOI: https://dx.doi.org/10.1016/j.cemconcomp.2011.11.002] 1:CAS:528:DC%2BC38XhtFWqurw%3D

57. Tantawy, MA. Effect of high temperatures on the microstructure of cement paste. J. Mater. Sci. Chem. Eng.; 2017; 5, 11 pp. 33-48. [DOI: https://dx.doi.org/10.4236/msce.2017.511004] 1:CAS:528:DC%2BC1cXhsV2qtbfN

58. Allahverdi, A; Ghorbani, J. Chemical activation and set acceleration of lime-natural Pozzolan cement. Ceramics-Silikáty; 2006; 50, 4 pp. 193-199.1:CAS:528:DC%2BD2sXhsFGmu7k%3D