Final Setting Time Research Articles

Experimental Investigation on the Effects of Coffee Husk Ash as Partial Replacement of Cement on Concrete Properties

The production of cement results in the depletion of natural resources and consumption of huge energy and CO2 emissions to the environment that cause global warming and climate change. To alleviate the problem, there is a growing interest of researchers to find an alternative material to partially cement by industrial and agricultural wastes. This research was therefore aimed to examine the potential of using coffee husk ash (CHA) as partial replacement for ordinary Portland cement (OPC) in C-25 concrete production. Concrete mixtures were prepared by partially replacing cement with CHA in different proportions (0%, 5%, 10%, and 20%) by weight with a constant w/c of 0.5. The consistency, setting time, workability, compressive strength, water absorption, sulphate attack, Fourier transform infrared (FTIR), and thermo gravimetric (TGA) tests were conducted on concrete samples. The test results revealed that the workability of mixtures showed a decreasing trend with an increase in the share of the CHA content in which the measured slump flow values ranged between 15 and 35 mm. Contrarily, the setting time of concrete mixtures showed an increasing trend with an increase in CHA content. The initial and final setting times were in the range of 67–126 minutes and 310–524 minutes, respectively, which is in the range of the standards. The compressive strength of concrete decreased with an increase in the share of the CHA, in which the results were measured in the range of 35.1–22.7 MPa for the 28th day sample with 5% and 20% of CHA, respectively. However, it increases as the curing days increase, whereas the water absorption of the concrete increases as the CHA increases but decreases as the curing days increase due to the porous nature of the CHA. From the study microstructure of concrete using Fourier transform infrared spectroscopy and thermogravimetric analysis, differential thermal analysis results show that the C-S-H gel would be from 950–1100 cm−1 wavenumber and at 500oC, and the CHA sample was decomposed and mass loss was observed at 500oC. In general, it was also observed that, from the compressive strength, the concrete satisfies its design strength up to 10% replacement level without compromising the performance of concrete.

Preparation and Performance Investigation of Optimized Cement-Based Sealing Materials Based on the Response Surface Methodology.

A new cement-based sealing material, which used Portland cement (PC) as a raw material and supplemented several gel components, such as accelerant, alkali activator, suspension agent, expansion agent, reinforcing agent, was prepared in this work. The effects of these components on the fluidity, setting time, and expansion rate of these sealing materials were investigated by an orthogonal test. The results show that the water–cement ratio and the reinforcing agent content, the accelerant content and the water–cement ratio, and the expansion agent content and the accelerant content are the most important influencing factors on fluidity, setting time, and expansion rate, respectively. In addition, the regression models and response surfaces of the factors were established using a multiple linear regression method. By this means, the influences of the two main factors on each performance of this sealing material were accurately and intuitively reflected for obtaining the optimal value in the optimization area. The results indicate that the sealing materials possess the best performances when the water–cement ratio is 1.1, the accelerant content is 50%, the expansion agent content is 0.1%, and the reinforcing agent content is 3%, which is corresponding to a fluidity of 360–380 mm, an initial (final) setting time of 60 (80)–80 (100) min, and an expansion rate of 2–12%. Furthermore, the microstructures of the optimized sealing material also reveal that the main hydration products of PC are transformed from layered Ca(OH)2 crystals into fine needle-like AFt crystals and C–S–H gels by the promotion effect of the optimizing ratio, thus leading to a more compact structure of optimized cement-based sealing materials.

Research on the synergy of micro-nano bubble water and alkali-free liquid accelerator to improve the early strength and hydration rate of cement

Alkali-free liquid accelerator additive has been widely used in shotcrete construction in recent years. However, due to their large dosage, high cost, poor adaptability, and insufficient early strength, there are certain difficulties in promotion and use. Because of its unique properties, micro-nano bubble (MNB) water can shorten the setting time of cement and increase the early strength of cement. Therefore, this study uses micro-nano bubble (MNB) water instead of ordinary water to be used in conjunction with an alkali-free liquid accelerator additive to improve the early strength. In this study, the addition of micro-nano bubble water can significantly shorten the initial and final setting time of cement paste, and the addition of micro-nano bubble water after cyclic shear for 8 min can increase the 1-day compressive strength of the cement mortar by 28.7% and the 7-day compressive strength by 22.7%. The late strength has no reduced phenomenon, and the flexural strength is also significantly improved, which effectively solves the problem of low early strength of the alkali-free liquid accelerator additive. It is analyzed and characterized by microscopic characterization methods such as SEM, XRD, hydration temperature test, the micro-nano bubble water used as mixing cement mortar water has a faster hydration process, better compactness, more uniform structure, faster consumption of C3S and C3A than ordinary water, and higher early hydration temperature peak.

Experimental Study on Strength Development and Engineering Performance of Coal-Based Solid Waste Paste Filling Material

To explore the strength development characteristics and engineering performance of different coal-based solid waste filling materials cemented into filling body, coal gangue was used as coarse material, fly ash, desulfurization gypsum, gasification slag, and furnace bottom slag as fine material, and cement as a gelling agent. The uniaxial compressive strength (UCS) and bleeding rate of coal-based solid waste cemented backfill (CBSWCB) were tested by an orthogonal experiment, and the influencing factors of mechanical properties and strength development were analyzed. The multiple generalized linear model of strength and bleeding rate was established, and the optimal filling material ratio was determined. The engineering performance index of CBSWCB with the optimal ratio was tested. The results show the following points: (1) the concentration and content of desulfurization gypsum had a great influence on the early compressive strength of CBSWCB, while fly ash, gasification slag, and furnace bottom slag had little influence on the early compressive strength. (2) High concentration, high content of fly ash and furnace bottom slag, low content of desulfurization gypsum, and gasification slag can significantly improve the early strength. High concentration and high content of fly ash, low content of gasification slag, furnace bottom slag, and desulfurization gypsum are beneficial to the later strength increase. (3) Under the optimal ratio scheme, the bleeding rate of CBSWCB was 1.6%, the slump was 16.6 cm, the cohesion was general, the segregation resistance was good, the initial setting time was 5.42 h, the final setting time was 7 h, and the early strength after curing for 8 h reached 0.24 MPa.

Development and Optimization of Geopolymers Made with Desert Dune Sand and Blast Furnace Slag

This study assesses the effect of mix design parameters on the fresh and hardened properties, cost, and carbon footprint of geopolymer mortar made with desert dune fines (DDF) and blast furnace slag (BFS). Taguchi method was employed in designing the experiments. Four factors were considered, each having three levels, leading to a total of nine geopolymer mortar mixes. The factors comprised the DDF replacement percentage, alkali-activator solution to binder ratio (AAS/B), sodium silicate-to-sodium hydroxide ratio (SS/SH), and sodium hydroxide (SH) molarity. Ten performance criteria were evaluated, including the flowability, final setting time, hardened density, 1, 7, and 28-day compressive strengths, water absorption, sorptivity, cost, and carbon footprint. ANOVA was carried out to estimate the contribution of each factor towards the response criteria. Further, TOPSIS analysis was utilized to optimize the mixture proportions of DDF-BFS blended geopolymer mortar. Experimental results showed that up to 25% DDF replacement enhanced the density, strength, and durability of the geopolymers with minor impact on the flowability and setting time. Higher replacement percentages had a detrimental impact on the performance but could still be utilized in specific mortar construction applications. The other factors had more limited contributions to the performance, evidenced by the ANOVA. TOPSIS method revealed the optimum mix to be made with DDF replacement of 25%, AAS/B of 0.5, SS/SH of 1.5, and SH molarity of 10 M. Different multivariable regression models were also developed to predict the fresh and hardened properties of the DDF-BFS geopolymer mortars using the mix design parameters.

Evaluation of date kernel powder (DKP) for potential use as setting and hydration retarder in concrete

The setting time of concrete is a major determinant of its workability. Increasing the water-binder ratio leads to improve workability, but concomitantly reduces the strength of concrete. Retarding admixtures are generally used to delay the setting time of concrete, especially in hot weather. Date kernels is one of the major waste product generated in Saudi Arabia and Middle east and utilization of date kernel powder (DKP) in concrete and other applications have been investigated with limited success. In this paper, results of an experimental investigation conducted to evaluate the potential of DKP as a setting retarder in concrete are presented. The cement was replaced by DKP at different replacement levels (0.5%, 1%, 2%, 3%, 4% and 5%) and different dosages of the commercial retarder were used (0.2%, 0.4%, 0.6%, and 0.8%). The effect of DKP and the commercial retarder on heat of hydration, thermal properties (thermal conductivity, resistivity and specific heat capacity), slump, density, compressive and tensile strength, and ultrasonic pulse velocity were investigated. The results showed that DKP had a significant effect on delaying the initial and final setting time of concrete and decreasing the evolution of heat of hydration and peak temperature when the DKP replacement quantities increased. However, the replacement of cement with DKP at a dosage greater than 2% resulted in a significant decrease in the compressive and tensile strength of the concrete. The density of the DKP concrete, thermal conductivity, specific heat capacity, and ultrasonic pulse velocity also decreased with increasing DKP dosage. The commercial retarder, on the other hand, had no significant effect on any of the measured properties.

Physical and Strength Properties of Cements Manufactured in Bangladesh: A Case Study

This study investigates the physical qualities and strength properties of representative cements manufactured by different brands in Bangladesh. The physical and strength properties such as normal consistency, initial and final setting time, density, specific gravity, fineness, and compressive strength of cement mortars as well as concrete cylinders were investigated experimentally. Using CEM II/B-M type cement, a total of 300 test specimens are prepared to determine those parameters. In this case study, specimens were prepared from ten different representative cement industries of Bangladesh and tested as per ASTM specifications. The experimental result shows that the physical and strength parameters of nearly all the representative cement samples are within the ASTM recommended ranges that ultimately proofs the quality of Bangladeshi Cement. The relationship between mortar and concrete strengths from the same batch of cement has also been investigated. Besides, a regression analysis has been conducted to find relationships between the concrete strength and their age of curing. The influence of initial and final setting times on concrete strength is also investigated. This study also provides the relationships between compressive strengths, between mortar and concrete cylinders at different ages. These age dependencies of concrete strength will help to predict the actual concrete strength at the early age of curing which may ensure faster construction work.

Insights into setting time, rheological and mechanical properties of chitin nanocrystals- and chitin nanofibers-cement paste

Chitin, the second most abundant biopolymer in nature, is available in the seafood industry's waste streams. In this pioneering study, chitin from waste shrimp shells was processed into chitin nanocrystals and nanofibers (Ch-NCs and Ch-NFs) for evaluation in the cement paste. The results show Ch-NCs delayed the final set time by up to 106 min, likely by electrostatic repulsion of cement particles, but Ch-NFs imparted only a max 78-min delay. Furthermore, the viscosity of fresh cement paste increased with Ch-NFs but did not significantly change with Ch-NCs. These different outcomes are attributed to more mobility of Ch-NCs rods versus the Ch-NFs network. In addition, nanochitin forms at 0.05 wt% of cement significantly increased 28d flexural strength by ∼40% and compressive strength by up to ∼12%. The encouraging results of this study indicate the promise of nanochitins in tailoring fresh and hardened properties of cement-based materials for target applications.

Effects of Gypsum and Limestone Powder on Fresh Properties and Compressive Strength of Concrete Containing Ground Granulated Blast Furnace Slag under Different Curing Temperatures

Usage of industrial by-products such as ground granulated blast furnace slag (GGBFS), gypsum, and limestone powder have gained prominence in concrete production. It is, therefore, very important to conduct research into the various materials and their attendant influence on properties of concrete at different ambient temperatures. This study focused on the slump, setting time, and compressive strength of concrete with GGBFS at a constant replacement ratio, in which different forms of gypsum, namely anhydrous and di-hydrate gypsum, were also added at different SO3 contents. Effect of addition of limestone powder was also investigated. The results of the tests indicated that both gypsum and limestone powder when added to a mix proportion containing GGBFS can improve slump and compressive strength of concrete. Anhydrous gypsum produced higher optimum compressive strength as compared with di-hydrate gypsum. An increase in SO3 content from gypsum contributed to strength development at early ages but reduced its long-term strength. Gypsum added to the mix delayed initial and final setting time. Limestone powder accelerated both initial and final setting times and contributed to increasing compressive strength after one day, thus three to seven days; however, the long-term strength was reduced. Curing temperature of concrete influenced strength development and the time required to remove formwork was determined for different mixtures using “maturity function”.

Effects of Fucoidan Powder Combined with Mineral Trioxide Aggregate as a Direct Pulp-Capping Material.

The development of direct pulp-capping materials with favorable biological and structural properties is an important goal in restorative dentistry. Fucoidan is a sulfated, fucose-containing polysaccharide obtained from brown seaweed, with a wide range of applications; however, its use as a direct pulp-capping material has not been examined. This study aimed to evaluate the mechanical, physical, and biological effects of fucoidan combined with conventional mineral trioxide aggregate (MTA) for direct pulp capping. The capping materials were created using Portland cement (80 wt%) and zirconium oxide (20 wt%) as base components, compared with base components plus 5 wt% fucoidan (PZF5) and base components plus 10 wt% fucoidan (PZF10). The initial and final setting time, compressive strength, chemical components, cell viability, adhesion, migration, osteogenesis, and gene expression were analyzed. Fucoidan significantly reduced the initial and final setting time, regardless of quantity. However, the compressive strength was lower for PZF5. Sulfur levels increased with fucoidan. The biological activity improved, especially in the PZF5 group. Cell migration, Alizarin Red S staining, and alkaline phosphatase activity were upregulated in the PZF5 group. Fucoidan is a useful regenerative additive for conventional pulp-capping materials because it reduces the setting time and improves cell migration and osteogenic ability.

Effect of limestone content on properties of portland limestone cement produced by intergrinding

Limestone is used very commonly as a mineral admixture in the production of blended Portland cement because of its availability and low cost. Since using limestone reduces the amount of clinker used, it helps to reduce CO2 emission from the cement production process. Limestone is added into cement commonly by intergrinding with clinker, gypsum and other admixtures (if any). International studies show that the influence of limestone depends not only on the content and fineness of limestone but also on the mineral composition of the clinker used. The objective of this study was to evaluate the influence of limestone content on some properties of Portland limestone cement produced by intergrinding method using materials available in Vietnam. The limestone contents used were 0, 10, 20, and 30%. The properties of the cement investigated include particle size distribution, water of consistency, setting time and compressive strength at ages of 1, 3, 7 and 28 days. The results show that, when increasing the limestone content, the cement particle size was distributed more widely, the water of consistency increased by 1%, and the initial and final setting time decreased slightly. The compressive strength also tended to decrease, the level of decrease was highest at the age of 1 day, gradually decreasing in the later ages. Based on the degree of strength decrease at ages of 3 and 28 days, the limestone content used should not be more than 20%.

Adverse Effects of Using Metallurgical Slags as Supplementary Cementitious Materials and Aggregate: A Review.

This paper discusses a sustainable way to prepare construction materials from metallurgical slags. Steel slag, copper slag, lead-zinc slag, and electric furnace ferronickel slag are the most common metallurgical slags that could be used as supplementary cementitious materials (SCMs) and aggregates. However, they have some adverse effects that could significantly limit their applications when used in cement-based materials. The setting time is significantly delayed when steel slag is utilized as an SCM. With the addition of 30% steel slag, the initial setting time and final setting time are delayed by approximately 60% and 40%, respectively. Because the specific gravity of metallurgical slags is 10–40% higher than that of natural aggregates, metallurgical slags tend to promote segregation when utilized as aggregates. Furthermore, some metallurgical slags deteriorate the microstructure of hardened pastes, resulting in higher porosity, lower mechanical properties, and decreased durability. In terms of safety, there are issues with the soundness of steel slag, the alkali-silica reaction involving cement and electric furnace ferronickel slag, and the environmental safety concerns, due to the leaching of heavy metals from copper slag and lead-zinc slag.

Use of natural compounds as a nutrition for bacteria in self-healing mortar

Microbiologically induced calcite precipitation, or calcium carbonate CaCO3, is used in remediating cracks and fissures in concrete. Since the microbial activity is pollution-free, natural, that process is extremely desired and may solve concrete cracking without sacrificing mechanical properties. The effects of different nutrient on the self-healing process are elucidated. Nutrients provide the required sources of energy for the bacterial growth and metabolic activities. A species of bacteria Bacillus sphaericus was added to the cement mix at a ratio of 0.6% of cement weight with three organic compounds for nutrients (calcium lactate, yeast extract and peptone) at 0.30% of cement weight. Effects on setting time, rate of water absorption, compressive strength and flexural strength were studied. It was found that bacteria nutrition acts as an accelerator for cement pastes for initial setting time mortar, while acts as a retarder of cement pastes for final setting time for all bacterial compared to control mortar. Finally, bacterial mortars with different types of nutrients showed an increase in compressive and flexural strengths with yeast extract showing the most promising enhancements, resulting in 26.5 and 60% increase in compressive and flexural strength respectively.

The Consistency, Setting Time and Compression Strength of Pozzolanic Materials: A Taguchi Gray Validation

Currently, the focus of research is on biocement mortar and concrete. To lower the cement substance by up to 40%, lime, fly ash, metakaolin, and silica fume are utilised. The major purpose of this study was to see if adding pozzolanic materials to biocement mortar may increase its setting time, consistency, and compressive strength, as well as the interaction of these pozzolanic components with cement mortar and concrete. The pozzolanic particles by sieving interaction to affirm the uniform molecule size equivalent to 1 µm. The compressive strength, consistency, and final setting time were estimated after the fruitful maturing of concrete blocks for around 28 days. As indicated by Taguchi investigation, the exploratory arrangement Level 10 gives the general best position among other trial designs with the GRG of 0.805. Besides, the weight level of metakaolin straightforwardly impacts the general exhibition of concrete substantial shapes rather than silica smoke, lime, and fly debris particles. The affirmation concentrates on uncovered improvement in the dark social grade of 1.92%, which is equivalent to the high compressive strength of 51.285 MPa, consistency territory between 29.5 to 38.5, and final setting time is 525 min. the impact of different pozzolanic substances on the concrete's consistency and setting time. It uncovered that by supplanting the 40% normal Portland concrete (OPC) with bio concrete, the concrete's consistency improves and the level of pozzolanic materials comparative with the level of OPC can build the concrete consistency restricts and lessen the use of bio concrete with minimal expense.

Fabrication of Radio-Opaque and Macroporous Injectable Calcium Phosphate Cement.

The aim of this work was the development of injectable radio-opaque and macroporous calcium phosphate cement (CPC) to be used as a bone substitute for the treatment of pathologic vertebral fractures. A CPC was first rendered radio-opaque by the incorporation of zirconium dioxide (ZrO2). In order to create macroporosity, poly lactic-co-glycolic acid (PLGA) microspheres around 100 μm were homogeneously incorporated into the CPC as observed by scanning electron microscopy. Physicochemical analyses by X-ray diffraction and Fourier transform infrared spectroscopy confirmed the brushite phase of the cement. The mechanical properties of the CPC/PLGA cement containing 30% PLGA (wt/wt) were characterized by a compressive strength of 2 MPa and a Young's modulus of 1 GPa. The CPC/PLGA exhibited initial and final setting times of 7 and 12 min, respectively. Although the incorporation of PLGA microspheres increased the force necessary to inject the cement and decreased the percentage of injected mass as a function of time, the CPC/PLGA appeared fully injectable at 4 min. Moreover, in comparison with CPC, CPC/PLGA showed a full degradation in 6 weeks (with 100% mass loss), and this was associated with an acidification of the medium containing the CPC/PLGA sample (pH of 3.5 after 6 weeks). A cell viability test validated CPC/PLGA biocompatibility, and in vivo analyses using a bone defect assay in the caudal vertebrae of Wistar rats showed the good opacity of the CPC through the tail and a significant increased degradation of the CPC/PLGA cement a month after implantation. In conclusion, this injectable CPC scaffold appears to be an interesting material for bone substitution.

Feasibility of sludge generated in water-based paint industries as cement replacement material

An estimated 2100 tonnes of solid sludge is generated per annum from the water-based paint industries of Bangladesh. This paint sludge (PS) is usually incinerated, consuming energy and generating greenhouse gases and other pollutants. Through chemical analysis and standardized tests, it was shown that PS contains a similar array of oxides as Ordinary Portland Cement (OPC) and has pozzolanic characteristics. Considering these, PS was examined as a cement replacement material to create an alternative and economically beneficial way of disposing of this waste. Cement paste and mortar samples were prepared by replacing 5%, 10%, 15%, 20% and 30% of OPC with PS. To assess mechanical and durability properties of PS-incorporated samples, different tests were carried out that included consistency, setting time, compressive strength, soundness, sulfate attack, alkali silicate reactivity and chloride diffusion. Both initial and final setting times of PS-incorporated cement increased with an increase in PS fraction but remained within the standard limit. Compressive strength increased for 5% PS replacement but decreased with further increase in PS replacement compared to 100% OPC mortar. A slightly higher rate of compressive strength gain was observed at later ages for PS-incorporated cement than 100% OPC, which confirmed the pozzolanic characteristic of PS. The addition of PS was found to reduce the expansion of mortar bars in both soundness and ASR tests. It also inhibited ettringite crystal formation in the mortar matrix for sulfate exposure. Initially, chloride permeability increased in the early days for PS-incorporated mortar but was found to decrease rapidly at later ages. Altogether, it may be concluded that a 15% replacement of OPC with PS would comply with the necessary strength and durability standards.

Grouting Material Development and Dynamic Grouting Test of Broken Rock Mass

To solve the problem of the unsatisfactory effect of grouting reinforcement in broken rock mass, a cement-based composite slurry was successfully prepared by using ordinary Portland cement as the main material in this study. By conducting a single factor test, orthogonal test, and organic compound modification test, the effects of different addition ratios of fly ash, clay and waterborne polyurethane, epoxy resin, and other organic materials on the grouting performance of cement slurry were analyzed. In addition, a grouting simulation test system was used to verify the reinforcement effect of the prepared composite slurry. The results indicate that the addition ratio of clay and fly ash has a strong influence on the strength and stone rate of cement slurry. The final setting time of the best mixed slurry can be shortened to 11 h, and the compressive strength after 28 days can reach 18 MPa. The composite slurry modified by organic materials has a reinforcement coefficient of up to 4.6 for crushed sandstone, which significantly improved the brittle failure phenomenon of the reinforcement stone body and, thus, has high application value.

Influence of Some Soluble Polymer Admixtures on the Hydration and Strength Development of Portland Cement Pastes

Hardening of cement pastes modified with 1 % polymers as methyl cellulose (MC), hydroxyl ethyl cellulose (HEC) and polyvinyl alcohol acetate (PVAA) comprises cement hydration and polymer effect on physicochemical and mechanical features of the modified cement pastes. Results showed that the water/cement ratio and setting times largely declined with polymers, where the values of water of consistency are 28.55, 25.69, 25.12 and 24.95 %, respectively. The initial setting times are 142, 134, 133 and 132, while the final setting times are 190, 185, 183 and 181 min., respectively. The incorporating of these polymers improves and enhances the bound water contents, bulk density, and compressive strength at 90 days curing, where the bound water contents are 13.26, 14.55, 14.73 and 15.29 %, the bulk density are 2.0369, 2.0413, 2.0421 and 2.0563 g/cm3 and the compressive strength are 62.23, 64.13, 65.25 and 68,71 MPa, respectively. The apparent porosity gradually declined as 22.12, 21.36, 20,84 and 18,82 %, respectively. The free lime contents are also diminished as 7.55, 6.18, 6.65 and 4.61 %, respectively. The rate of hydration was retarded at early ages of hydrating, while was improved and enhanced at the later ages. The obtained results are confirmed with Isothermal Calorimetry, thermal analysis, and FT-IR spectra. Despite the early reduction of the hydration reactions, a higher grade of hydration is observed after 90 days of hydration for the modified cement pastes according to the better dispersion of the cement grains during mixing and casting.

Combined Use of Phosphoric Acid Modified Steel Slag and Protein Material for Retarding of Β-Semi-Hydrous Gypsum

Building gypsum has the disadvantage of short setting time and fast hardening characteristics. Based on the systematic experiments, a combined retarding system of phosphoric acid modified steel slag (3%, gypsum-based) and protein-based material (Sika 200P 0.005%, gypsum-based) is proposed. The initial setting time of gypsum is prolonged to 206 min and the final setting time is 221 min. The retarding effect for desulfurization building gypsum is significantly better than Sika 200P, and the cost is greatly reduced.

Electro-Mechanical Impedance Technique for Assessing the Setting Time of Steel-Fiber-Reinforced Mortar Using Embedded Piezoelectric Sensor

The electro-mechanical impedance (EMI) change in Piezoelectric (PZT) sensors embedded in steel-fiber-reinforced mortar (SFRM) was investigated to assess the material setting time. The EMI was continuously monitored for 12 h by the PZT sensor embedded in SFRM having fiber volume fraction of 0.5%, 1.5%, and 2.0%. The initial and final setting time of the SFRM were estimated using EMI signal change. The penetration resistance test, a conventional test method for the setting time of cement mortar, was also conducted. In the penetration resistance test, it was observed that the initial and the final setting time of SFRM accelerated as the volume fraction of the steel fiber increased. On the other hand, in the EMI sensing technique, the initial and the final setting time of the SFRM were consistent regardless of the fiber volume fraction.