Compressive Strength Characteristics Research Articles

Study on the influence of rock bridge angle on the size effect of rock uniaxial compression.

As a basic parameter of rock, the rock bridge angle plays an important role in maintaining the stability of rock masses. To study the size effect of rock bridge angle on the uniaxial compressive strength of rocks, this paper adopts the principle of regression analysis and combines numerical simulation to carry out relevant research. The research results indicate that: (1) the uniaxial compressive strength decreases with the increase of the rock bridge angle, showing a power function relationship; (2) The uniaxial compressive strength decreases with the increase of rock size and tends to stabilize when the rock size is greater than 350 mm, showing a significant size effect. (3) The fluctuation coefficient of compressive strength increases with the increase of rock bridge angle and decreases with the increase of rock size; When the rock size is 350 mm, the fluctuation coefficient is less than 5%; (4) The characteristic compressive strength and characteristic size both increase with the increase of the rock bridge angle.

Experimental Study on the Strength and Damage Characteristics of Cement–Fly Ash–Slag–Gangue Cemented Backfill

In order to achieve the goal of effectively utilizing solid waste resources and improving mining stability, it is necessary to incorporate various types of solid wastes in the production of cemented backfill. For investigating the compressive strength and damage characteristics of Cement–Fly Ash–Slag–Gangue (CFSG) cemented backfill under loading, real-time X-ray Computed Tomography (CT) scanning was employed to capture two-dimensional (2D) grayscale slices and three-dimensional (3D) fracture models during uniaxial compression testing. The study quantitatively assessed the evolution of cracks and microstructural damage in CFSG cemented backfill. The results indicate that the specimens underwent four stages of transformation, including compaction, linear elasticity, yielding, and residual deformation, during the uniaxial compression process. The specimens exhibited a measured compressive strength of 3.44 MPa and a failure strain of 0.95%. As the axial strain increased, there was an increase in 2D porosity observed in the CT images and a greater dispersion of crack distribution. A 3D model constructed from CT slices illustrated the feature of cracking expansion, with the fracture volume gradually increasing during the elastic deformation phase and experiencing rapid growth during the yielding and residual deformation phases. The damage variable, obtained from the volume of 3D cracks, exhibited a slow-growth pattern, characterized by a rapid increase followed by a more gradual rise with the increase in axial strain. This study serves as a significant reference for comprehending the micro-mechanisms involved in the damage process and cracking characteristics of cemented backfill mixed with solid wastes under external loading conditions.

Effects of different cooling methods on the resistance to chloride ion penetration in concrete produced with slag-modified cement and exposed to elevated temperatures

The deterioration of reinforced concrete elements is associated with the ingress of aggressive agents through the concrete capillary pores. The exposure to elevated temperatures can be a serious concrete degradation factor, depending on its intensity and the cooling procedures. This paper presents a quantification of the effects of slow cooling (SC) and fast cooling (FC) methods on the chloride-ions penetration into fire-damaged concretes produced with a slag-modified cement. A (2 × 4 × 2) factorial experimental program was designed to evaluate the diffusion of chloride ions within different types of concrete (characteristic compressive strengths of 20 MPa and 35 MPa) before (25 °C) and after exposure to different high temperature levels (200 °C, 500 °C and 700 °C) and cooling procedures (SC and FC). Chloride diffusion coefficients were used to estimate the service life of the concretes and scanning electron microscopy was used to investigate the microstructural mechanisms behind the durability results. The exposure of concrete to high temperatures compromises its durability, as thermal cracking propagation and porosity increases tend to facilitate the penetration of aggressive agents and the diffusion of chloride ions. The use of the slag-modified cement did not provide significant benefits to the durability of concretes exposed to 200 °C and the effects of different cooling methods on the chloride ions permeability were very noticeable. In contrast, statistical analyses did not detect significant difference between the effects of SC and FC for concretes exposed to 500 °C or 700 °C.

Establishing the Characteristic Compressive Strength Parallel to Fiber of Four Local Philippine Bamboo Species

Bamboo is considered a sustainable construction material due to its ability to grow quickly and its mechanical properties that are comparable to timber. Contributing to the current effort to establish structural bamboo standards in the National Structural Code of the Philippines (NSCP), this study establishes the characteristic compressive strength of four bamboo species: Bambusa vulgaris (36 samples), Dendrocalamus asper (36 samples), Bambusa blumeana (94 samples), and Guadua angustifolia Kunth (30 samples). The samples were subjected to compressive loading following ISO 22157-1 (2017). The characteristic compressive strength values obtained, according to ISO 12122-1 (2014), were 40.35 MPa for B. vulgaris, 40.21 MPa for D. asper, 46.63 MPa for B. blumeana, and 36.99 MPa for G. angustifolia Kunth. Simple linear analysis, one-way ANOVA, and Welch’s t-test were used to analyze the correlation models and establish a comparative analysis of the effects of nodes and geometric and physical properties on the compressive strength of bamboo samples. In comparisons of the characteristic compressive strengths obtained from this study to the strengths of unseasoned structural timber of Philippine woods, all bamboo species showed higher strength values than did other woods, and bamboos thus have great potential as an alternative construction material to timber.

Experimental Evaluation of Mechanical Properties, Micro Structure and Post-Fire Strength of Fiber Reinforced Geopolymer Concrete

Geopolymer mixtures offer an enhanced alternative to implement an eco-friendly solution in construction industry. These mixtures exhibit similar or better mechanical and structural properties in comprising of cement and can use recycling and by-product materials. Against this background, an eco-friendly advantageous were achieved from the engineers and researchers by using waste materials to replace cement and attention to reduce CO2 emission during its procedure. This study attempted to evaluate compressive and tensile strength, micro structure and post-fire characteristic of the geopolymer mixtures. For this aim, the geopolymer mixtures were exposed to elevated temperature between 200, 500 and 800 0C. Then, the post-fire and mechanical behaviour were investigated. The proposed research supported the slight decrease in the GPC's compressive stress by fibres, and the 1.25% PP fibres displayed the least performance, indicating nearly 13% decrease than the unreinforced mixtures. As exhibited by the post-fire behaviour of mixtures, the GPC's compressive strength increased first for all mixes but in the range of 400 - 800°C it decreased at a higher rate because of the geopolymer matrix-related dehydration. Besides, fiber melting under high temperatures and the thermal reaction procedure related to free water evaporation reduce the mechanical properties under temperatures ranging from 400°C to 800°C. DOI: https://doi.org/10.52783/pst.349

Sustainable Production of Self Compacting Concrete by using Fly Ash and Granite Waste

The development of sustainable concrete has gained plenty of awareness in recent years. Researchers have conducted many experimental investigations for the manufacture of different forms of concrete by using numerous low carbon footprint materials, such as granite waste and fly ash. The using of low carbon footprint materials in construction industry will minimize the exploitation of natural raw materials and promote sustainability in construction industry. This research thus aimed to investigate the influence of granite waste (GW) and fly ash on the production of self-compacting concrete (SCC). The preliminary investigation was carried out for finding the maximum adding percentage of GW and fly ash in the successful production of SCC. The GW was used in the proportion of 10,20 and 30% as an alternative to fine aggregate (i.e. sand) by weight, while, fly ash was substituted with cement in the proportion of 10,20 and 30% by weight. The fresh characteristics (slump flow, V-funnel, and L-box), mechanical characteristics (compressive strength) were evaluated. The findings revealed that the combined use of GW (up to 30%) and fly ash (up to 30%) in SCC has the potential to considerably enhance the fresh and water absorption properties (without adversely affecting strength characteristics

Microstructure and deterioration mechanism of hydraulic concrete under variable temperature dry-wet cycles

In the variable water level area, hydraulic concrete structures are susceptible to variable temperature and alternating dry-wet cycles, especially for thin-walled structures. To elucidate alterations in the microstructure and strength of hydraulic concrete subjected to variable temperature dry-wet cycles, this paper firstly conducted a durability test on hydraulic concrete. Subsequently, CT scan images of the specimens are acquired during the variable temperature dry-wet cycle. Secondly, in view of the shortcomings of existing threshold methods for CT image pore segmentation, a new image segmentation method (RASLPSO-TV-Top-hat) is proposed by using Tensor voting and Top-hat technology, combined with a Reverse Adaptive Particle Swarm Optimization algorithm with Self-Learning ability. The evolution process of pore structure (microcracks) of hydraulic concrete under the variable temperature dry-wet cycles is captured. Thirdly, an in-depth analysis is conducted on the compressive strength and acoustic emission characteristics. The analysis shows that with the number of cycles increases, there is a discernible interconnection among the pore structures. This interconnection leads to a noteworthy reduction in the compressive strength of the concrete. Additionally, the cumulative number of Acoustic Emission ringing events exhibits an initial rise followed by a subsequent decline. The study successfully identifies the patterns governing the deterioration of strength and microstructure evolution in hydraulic concrete. The mechanism underlying the decline in performance of hydraulic concrete under variable temperature dry-wet cycles is elucidated. It provides a reliable and valuable basis for the safety assessment of hydraulic concrete structures in the variable water level area.

Experimental Investigation of Sustainable Concrete Production using Blast Furnace as A Cement Substitute- A art of Review

The pursuit of sustainable construction practices has led to a growing interest in alternative materials that can reduce the environmental impact of traditional concrete production. This experimental study focuses on the utilization of blast furnace slag as a substitute for cement in concrete, aiming to assess its mechanical properties, environmental impact, and overall sustainability. The primary objectives of this research are threefold. Firstly, the study seeks to evaluate the mechanical properties of concrete by varying the content of blast furnace slag in the mix, with a specific emphasis on strength, durability, and structural performance. This involves conducting a comprehensive analysis of the concrete's compressive strength, flexural strength, and other relevant mechanical characteristics. Secondly, a life cycle assessment (LCA) will be employed to analyze the environmental impact of the concrete mixtures. This assessment will compare carbon dioxide (CO2) emissions, energy consumption, and overall sustainability of the concrete produced with varying percentages of blast furnace slag. The LCA will provide valuable insights into the environmental implications of using slag as a cement substitute, aiding in the identification of eco-friendlier concrete production practices. Lastly, the research aims to assess the environmental impact of blast furnace slag itself when employed as a cement substitute. This involves examining the production, transportation, and incorporation of blast furnace slag into the concrete mix, providing a holistic view of its sustainability across the entire life cycle. The experimental approach involves the meticulous design of concrete mixes with different percentages of cement replaced by blast furnace slag. The varying mix designs will be tested for mechanical properties, and the data obtained will be used to draw correlations between slag content and concrete performance. In summary, this research endeavors to contribute to the body of knowledge surrounding sustainable concrete production by exploring the mechanical, environmental, and sustainability aspects of utilizing blast furnace slag as a cement substitute. The findings of this study are anticipated to provide valuable insights for the construction industry to adopt more environmentally friendly practices while maintaining or enhancing concrete performance.

Exploring the geotechnical and microstructural properties of composite mixtures for landfill liner materials: an experimental investigation.

The present study directs the need for the development of an economical composite mix comprised locally available soil and industrial waste which satisfy the design parameters of the municipal solid waste (MSW) landfill. The local soil, bentonite, and fly ash mixtures are mixed in different proportions to evaluate the geotechnical and microstructural characteristics for suggesting an optimum composite mix that fulfills the design parameters of landfill liners. The curing periods of different mixes are also considered while evaluating the unconfined compressive strength (UCS) characteristics. The microstructure of the mixtures is examined using advanced imaging techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDAX) to gain insights into the changes at the microscale level due to the inclusion of fly ash. It is observed that soil-bentonite-fly ash composite mix in a ratio of 65:15:20 aligns with the optimal design characteristics required for a landfill liner. Notably, for this composite mix, both liquid limit (LL) and plastic limit (PL) show a significant increase of 48.57% and 32.33% respectively, while the optimum moisture content (OMC) rises by 11.25%. Conversely, maximum dry density (MDD) experiences an 8.79% decrease. Moreover, the free swell index (FSI) escalates by 113%, whereas hydraulic conductivity (HC) records a substantial reduction of 96.04%. Moreover, the UCS exhibited a notable increase of 209% after a 28-day curing period. The highest strength is achieved initially by soil mixed with 20% fly ash, followed by a blend containing 15% bentonite. Therefore, proper fly ash content in filler and other binder materials is an effective and sustainable approach that not only solves the disposal issue but also enhances the material's engineering characteristics, justifying its suitability to be used as a landfill liner.

Fresh, Compressive and Direct-Tensile characterization of Engineered Cementitious Composite

A new category of high-performance fiber-reinforced composite broadly known as Engineered Cementitious Composite (ECC) has gained rapid attention in the construction industry in recent years. The exceptional behaviour of ECC, therefore high ductility, toughness, and durability, make it a promising material for various structural applications such as tunnel inner lining, dam and bridge deck slab construction. This investigation aims to study the fresh and mechanical characteristics of ECC, including workability, compressive, and direct tensile strength. A total of 15 ECC mixes are prepared with varying superplasticiser-binder ratio (0.200, 0.225, 0.250, 0.275 and 0.300 %), sand-binder ratio (0.35, 0.40 and 0.45) and a constant water-binder ratio (0.27). The mini-slump cone test was performed to examine the workability of the fresh ECC mixtures. The results showed that using a higher content of the superplasticiser resulted in an upsurge in both the workability of the fresh ECC mixtures and the mechanical strength of ECC, particularly the tensile strength. Apart from this, both the mechanical tests are performed at the 7 and 28 days. As per the results, both the compressive strength and direct tensile strength of ECC are found to be comparatively higher than that of the conventional mix. In conclusion, ECC is an efficient construction material for various structural applications, especially for the latest 3D printing construction techniques. The uniform dispersion of fibers significantly improves the tensile strength and ductility of ECC, making it a suitable material for seismic-resistant structures.

Enhancing the engineering characteristics of sustainable recycled aggregate concrete using fly ash, metakaolin and silica fume

The present global environment is facing growing issues linked to production of concrete, mostly due to high consumption of concrete as the dominating construction material globally. In today's climate of environmental sustainability, recycled concrete production using RA (recycled aggregates) requires a more holistic approach. This study examined how recycled aggregate (RA), metakaolin, silica fume and fly ash affect mechanical characteristics (compressive strength, split tensile strength), and durability characteristics (acid resistance, absorption, sorptivity) of concrete. The objective of this investigation is to figure out how the potential of RA based concrete can be improved so that they can be used to their maximum extent. To achieve the desired outcome, the study involved testing three distinct groups of concrete samples, each containing different percentages (25%, 50%, and 75%) of recycled aggregate (RA) with a constant amount of silica fume, (25 kg/m3). The first group was used as the control mix, while the second group incorporated 10% fly ash, and the third group included 15% metakaolin. The findings of this research show that the RA concrete mechanical properties as well as durability can be significantly improved by incorporating 15% metakaolin and 10% fly ash. The investigation involves the examination of all ternary blends within two distinct acidic environments, specifically a 5% hydrochloric acid (HCl) solution and sulfuric acid (H2SO4). Both the ternary mixes (metakaolin and fly ash) with the combination of silica improve all characteristics. The quality assurance, cost analysis and the reduction of CO2 emissions are carried out, utilizing RA (recycled aggregates) as a substitute for NA (natural aggregate). In case of producing superior structural concrete, it is recommended based on results to limit the replacement percentage of recycled aggregate (RA) to a maximum of 50% in presence of 10% fly ash and 15% metakaolin, otherwise the RA replacement percentage should not be more than 25%.

Experimental Study on the Compressive Strength and AE Characteristics of High-Temperature–Treated and LN 2 -Cooled Sandstone

Experimental Study on the Compressive Strength and AE Characteristics of High-Temperature–Treated and LN ₂ -Cooled Sandstone

Effect of Precursor Blending Ratio and Rotation Speed of Mechanically Activated Fly Ash on Properties of Geopolymer Foam Concrete

This research used fly ash and slag to create geopolymer foam concrete. They were activated with an alkali, resulting in a chemical reaction that produced a gel that strengthened the concrete’s structural integrity. The experimental approach involved varying the fly ash content in the precursors at incremental percentages (10%, 30%, 50%, 70% and 90%) and subjecting the fly ash to mechanical activation through a planetary ball mill at distinct rotational speeds (380, 400, 420 and 440 rpm). The investigation discerned that the fly ash content and particle structure exert a discernible influence on macroscopic properties, including flowability, air generation height, compressive strength, dry density and microstructural characteristics such as pore distribution and hydration product arrangement in the geopolymer foam concrete. Employing analytical techniques such as X-ray diffraction (XRD) and scanning electron microscopy (SEM), it was deduced that diminishing the fly ash content correlates with an enhancement in compressive strength. Furthermore, the specific strength of the geopolymer foam concrete reached a peak of 0.041 when the activated fly ash in the planetary ball mill rotated at 420 rpm, manifesting a lightweight and high-strength outcome.

Analysis of the manufacturing of concrete paving blocks with by-products from thermoelectric power plant

The key factor in constructing urban roads applying interlocking concrete block pavement (ICBP) is to employ an appropriate design method for better effectiveness. Concrete paving blocks (CPB) can also be manufactured using industrial by-products. Then, this paper aims to analyze CPB with coal bottom ash (CBA) from a Thermoelectric Power Plant through mechanical characterization and design methods for ICBP. To this end, tests, such as void index, water absorption, compressive strength, and elasticity modulus, were done on CPB for each mixture. Furthermore, empirical and mechanistic-empirical design methods for ICBP were applied. Then, four dry concrete mixtures (two with CBA and two without CBA) were designed with two water/cement ratios (0.63 and 0.73) to produce rectangular CPB measuring 20 cm × 10 cm × 8 cm (length × width × thickness) by a vibro-press machine. Furthermore, ICBP sections were designed, applying six simulations from empirical and mechanistic-empirical design methods. The results showed that the mixtures A73 and B73 with more water, i.e., water/cement ratio of 0.73, presented higher characteristic compressive strength at 28 days (25.34 MPa and 15.88 MPa, respectively) than the other mixes A63 and B63 with less water, i.e., water/cement ratio of 0.63 (these two mixes showed 15.85 MPa). Furthermore, the CPB application for bike paths or parking areas was allowed according to the Australian specification of 15 MPa for compressive strength test. Also, all ICBP sections from the mechanistic-empirical design required approximately 24.9% fewer materials for the sub-base layer than the empirical process. Finally, the CPB application is possible for areas with light traffic, and the ICBP technology was more feasible with the mechanistic-empirical design method.

Effect of Temperature Gradient on Compressive Strength and Strain Characteristics of Coarse-Grained Frozen Soil

Effect of Temperature Gradient on Compressive Strength and Strain Characteristics of Coarse-Grained Frozen Soil

Effect of Silica Fume Concentration and Water–Cement Ratio on the Compressive Strength of Cement-Based Mortars

This study investigated how the water–cement ratio and silica fume concentration affect the compressive strength of cement mortars. This comprehensive study delved into the intricate interplay between water–cement ratio and silica fume concentration, examining their influence on cement-based mortars’ compressive strength and water absorption characteristics. The silica fume concentration was investigated, ranging from 5% to 15% of the cement weight. The investigation employed two distinct mixing techniques, mixing cement and silica fume, before extracting appropriate samples; alternatively, a magnetic stirrer was used to prepare samples by dissolving silica fume in water. The cement mortars were also prepared with three different water–cement ratios: 0.44, 0.47, and 0.5. The interesting findings of compressive tests illuminated a consistent trend across all curing days and mixing methods—a reduction in the water–cement ratio corresponded with a notable increase in compressive strength. However, it is essential to note that the influence of the mixing method on the compressive strength of cement-based mortars is based on the water–cement ratio. The results show that by using the suggested technological method, it was observed that samples prepared with water–cement ratios (W/C) of 0.47 and 0.44 exhibited higher compressive strengths compared to those prepared using the well-known standard mixing method. The compressive test results underscored that the water–cement ratio reduction consistently enhanced the compressive strength in every combination of curing days and mixing techniques. Furthermore, this reduction in the water–cement ratio was correlated with a decrease in water absorption of the mortar. Conversely, the water–cement ratio itself played a pivotal role in defining how the mixing technique affected the compressive strength and water absorption of cement-based mortars. This multifaceted exploration underscores the nuanced relationships between key variables, emphasizing the need for a comprehensive understanding of the intricate factors influencing the mechanical and absorptive properties of cement-based materials.

Strength Optimization of Nanocomposite Cementitious Materials Using Nanoscale Modifications

Represent Volume Element (RVE) is broadly used by investigators to control the properties of nano-cementitious materials. This paper focuses on analyzing a set of RVE data and proposes parametric equations for determining the compressive and flexural strength characteristics (σc and σf). Primarily, a parametric study is performed with RVE analysis. The essential design parameters are used to fit rational equations. The RVE data are also applied to train artificial neural networks of σc and σf. RVE, neural networks, and rational equations are correlated. Regression equations are validated with the experimental study. SEM, TEM, XRD, and FTIR results are carried out in the microscopic and mechanical analysis for carbon nanofiber cement composites, which can lift their strength, constancy, integrity, and density and reinforce the composite microstructure. Lastly, the Pareto-optimal design results are presented with a multi-objective optimization problem.

Failure Behavior and Fracture Evolution Mechanism of Coal with Fissures around Holes.

The fracture of coal is the main channel of gas flow and an important factor affecting the stability and efficiency of gas drainage boreholes. The coal structure, the development of hole cracks, and the degree of deformation are different. It affects the strength and mechanical deformation characteristics of coal to a great extent. In order to investigate the law of fracture evolution around the borehole of fractured coal, uniaxial and triaxial compression tests of raw coal samples have been carried out. The stress field evolution characteristics of fractured coal under compression were analyzed by Particle Flow Code (PFC2D). The strength, deformation, and fracture evolution behavior of fractured coal around boreholes under different confining pressures were studied. The results show that the compressive strength and fracture morphology evolution characteristics of coal around the hole are obviously related to the confining pressure and fracture occurrence of raw coal. The borehole structure itself has an important influence on the distribution location of the shear failure zone of the fracture around the hole, and its influence degree increases with the decrease of borehole confining pressure. During the deformation of coal with cracks around the hole, the initiation, propagation, and union behavior of cracks are related to the crack angle β. The cracks with β 0 and 180° are most easily closed during compression and the cracks with β 90° have little effect on the crack propagation zone. When the crack angle β is 45°, it is most easy to sprout and expand at the end; when the coal is compressed to the ultimate strength, the increase rate of the tensile crack increases, and the polymerization and combination behavior of the crack is more obvious. The evolution cloud map of the stress field can better reflect the evolution characteristics of fracture development, expansion, and fracture in the process of coal loading. Studying the failure behavior and fracture evolution mechanism of the coal around the hole can better predict and control the gas migration and extraction effect, which is of great significance to prevent the occurrence of gas accidents.

Anisotropy characteristics of electrical conductivity and compressive strength of 3D carbon fiber/epoxy angle-interlock woven composites

Electrical and compressive performances are important in 3D carbon fiber/epoxy angle-interlock woven (AIW) composites for mechanical-electrical coupling behaviors. Here we investigate the electrical conductivity and compressive strength of.3D AIW composites both in in-plane and out-of plane. Four-probe method is conducted to measure the volume resistance along different directions. Damage evolution and failure modes are recorded with a high-speed camera during compressive test. Electrical conductivity and compressive strength exhibit obvious anisotropic characteristics due to fiber orientation and yarn waviness. The curved warp yarns result in the compromise of the X-direction conductivity by extending the current transmission length and increase of the Z-direction conductivity by forming more contact points to expand the current flow paths. Because of different yarn arrangements, the compressive failure mechanisms of 3D AIW composites in the X, Y and Z directions are buckling failure, double shear bands and indirect tensile failure, individually. Yarn undulation in the X-direction causes premature buckling and exhibits elastic-plastic nonlinear response, resulting in the lowest compressive strength and modulus. The 3D AIW composites have the lowest electrical conductivity and highest compressive strength in the Z-direction, which is suitable for high strength stress-sensing elements.

Comparison between Four-Probe and Two-Probe Electrical Resistivity Measurement to Monitor the Curing and Piezoresistivity Behavior of Smart Cement Paste Modified with Waste Steel Slag and Green Nano-magnetite

Abstract This study aims to examine the compressive strength, electrical resistivity, and piezoresistivity characteristics of ordinary Portland cement (OPC) with a constant water-to-cement ratio (w/c) of 0.38. The optimal value of steel slag (SS) was determined to be 5 % based on the compressive strength of six different mixes of cement paste modified with various SS from 0 % to 30 % weight of cement. Additionally, the investigation will include modified cement samples containing 1 % green synthesized material and commercially available nano-magnetite (NM). Because iron is the primary component of SS and NM, the electrical resistivity, which is the primary criterion for structural health monitoring of cementitious material, can be increased by adding SS and NM. Hence, a comparative analysis was conducted to assess the resistivity of cement paste throughout the early curing period up to 28 days using an alternative current (AC) and embedding wires into the specimen, employing both the two-probe (2P) and four-probe (4P) methodologies. The findings suggest that the 4P method is a more precise approach for determining electrical resistivity than the 2P method, as the wire probe is not considered in the 4P method. Hence, it is imperative to compute the correlation between the 2P and 4P methodologies in order to attain a precise resistivity measurement. The suggested model indicates that the expected 4P resistivity can be measured with high precision, a high coefficient of determination (R2) of .97, and a low root mean square error (RMSE) of 7.33 Ω·m, based on the 2P result. The piezoresistivity results demonstrated that the cement paste modified with green synthesis nano-magnetite (GSNM) had a higher electrical resistivity (ER) change, 10.85 % greater than cement paste only, 57 % higher than cement modified with SS, and 34.2 % higher than cement paste modified with commercial nano-magnetite (CNM) after 28 days of curing. In addition, the compressive strength of cement paste modified with GSNM was higher than that of cement paste, cement paste modified with SS, and cement paste modified with CNM by 15.96 %, 21 %, and 1.7 %, respectively, after 28 days of curing. A Vipulanandan p–q model was used to forecast the electrical resistivity of cement paste versus time at start hydration during 28 days of curing and the change of electrical resistivity versus compressive strength at 3, 7, and 28 days. The Vipulananda p–q model anticipated both electrical resistivity and piezoresistivity behavior well.