Strength Of Aggregates Research Articles

Utilization Of Thromboelastography With Platelet Mapping For Prediction Of Poor Wound Healing And Infection In Postoperative Vascular Patients

INTRODUCTION AND OBJECTIVES Microvascular disease and increased platelet aggregation have been cited as contributing factors to poor wound healing and infection. Thromboelastography with platelet mapping (TEG-PM) provides a measurement of clot strength that factors in medication effects, including individual drug resistance. This may provide insight into patient-specific risk factors and an opportunity to prevent wound infections/dehiscence. This prospective, observational study aimed to determine if TEG-PM could identify patients more likely to experience postoperative wound infections/dehiscence following extremity revascularization. METHODS All patients undergoing named vessel revascularization during December 2020-August 2021 at a large tertiary institution were prospectively included. TEG-PM assays were performed on patients immediately pre-operatively and at serial intervals postoperatively up to six months. RESULTS CONCLUSIONS TEG-PM revealed a significantly higher level of platelet aggregation and clot strength (MA) with diminished platelet inhibition in patients with infection/dehiscence events following revascularization procedures, indicating that their microvascular flow may be compromised. This novel insight may expose an integral factor for at-risk patients and provide an opportunity for individualized intervention following revascularization. Microvascular disease and increased platelet aggregation have been cited as contributing factors to poor wound healing and infection. Thromboelastography with platelet mapping (TEG-PM) provides a measurement of clot strength that factors in medication effects, including individual drug resistance. This may provide insight into patient-specific risk factors and an opportunity to prevent wound infections/dehiscence. This prospective, observational study aimed to determine if TEG-PM could identify patients more likely to experience postoperative wound infections/dehiscence following extremity revascularization. All patients undergoing named vessel revascularization during December 2020-August 2021 at a large tertiary institution were prospectively included. TEG-PM assays were performed on patients immediately pre-operatively and at serial intervals postoperatively up to six months. TEG-PM revealed a significantly higher level of platelet aggregation and clot strength (MA) with diminished platelet inhibition in patients with infection/dehiscence events following revascularization procedures, indicating that their microvascular flow may be compromised. This novel insight may expose an integral factor for at-risk patients and provide an opportunity for individualized intervention following revascularization.

Microscopic analysis of the evolution of asphalt colloidal properties and rejuvenation behavior in aged asphalt

The performance restoration of aged asphalt is a challenge in the current technology available for pavement rejuvenation. Investigating the evolution of aged asphalt colloids from a microscopic perspective is the key to solving this problem. In this study, asphalt colloids and aggregates were modeled according to molecular simulation. The thermodynamic properties of colloids were investigated by viscosity and cohesive energy density (CED). The microstructural evolution and energy in colloids were examined using radial distribution function (RDF), binding energy, electrostatic potential (ESP), and interaction potential curve after annealing simulations. Rejuvenators were introduced into the aged asphalt colloid and aggregate models to investigate asphalt rejuvenation behavior. The thermodynamic and colloidal microstructural changes caused by these configurations were further verified. The results showed a significant increase in viscosity and CED of aged asphalt colloids. The results of RDF and quantum mechanical calculations indicate that oxidative aging enhances the strength and density of asphaltene aggregates and also contributes to forming stable rejuvenated configurations. Under the influence of rejuvenators, asphaltene aggregates can form four rejuvenated configurations: “block,” “sandwich,” “T-shape,” and “occupy.” The sandwich and occupy configurations are characterized by the stacking effect of aromatic rejuvenators. The block configuration is caused by the steric hindrance effect of long-chain rejuvenators. The T-shape configuration is common in both effects. The polarity of rejuvenators improves electrostatic interactions and contributes to rejuvenation configurations, but also leads to extra hydrogen bonds and enhanced aggregation. The rejuvenation of aggregates can be considered the formation of new stable configurations under thermal motion. Recovery results of aged asphalt indicate that effective rejuvenation can be achieved using low-polarity aromatic rejuvenators and high-polarity long-chain rejuvenators.

Optimizing lightweight expanded clay aggregate coating for enhanced strength and chloride resistance

Lightweight expanded clay (EC) aggregates help in decreasing the dead load of the structure and reduce the concrete demand in foundations and other major structural members. However, a major drawback is their high water-absorption and permeability which degrades the transport properties of the concrete, and low strength which results in a concrete too weak to actively participate in load bearing. The present study demonstrates a solution to improve the performance of EC aggregates by coating with different cementitious composites before adding in the lightweight concrete (LWC). Two coating mixes, cement with silica fume and cement with fly-ash, were used to coat EC aggregates with multiple layers. The effect of coat thickness on the density, strength, and cost of EC was examined. The coated EC (CEC) aggregates showed a 60% decrease in the water absorption test, and a 200% increase in the aggregate strength. The concrete made using CEC showed up to 150% increase in the specific compressive strength, and up to 50% drop in the charge passed during rapid chloride permeability tests. Among the coats, the fly-ash (FA) mixes performed at par with the silica fume (SF) mixes in all the tests. Costing index calculated using the cost and specific strength of the LWCs showed a reduction with increasing no. of coats. Considering the high cost of SF, the use of FA coated EC aggregates is recommended to improve the concrete performance and justify the cost involved in their production.

Labor Unions and Voter Turnout in the American States: Direct Versus Indirect Mobilization

AbstractI examine the relationship between labor unions and voter turnout in the American states. Though it is well known that unions increase turnout directly, we know less about their indirect effects. Moreover, the indirect effects may consist of nonmember mobilization and aggregate strength. To examine the direct and indirect mechanisms, I analyze both state-level panel data and individual-level data with a multilevel approach. First, my panel analysis shows that unions are positively associated with turnout as expected. Yet, the association is observed only in midterm elections, but not in presidential elections. Second, more importantly, my individual-level analysis suggests that indirect nonmember mobilization and indirect aggregate strength are positively related to turnout, while direct member mobilization is not. The findings imply that the direct effects are limited and, thus, that decreasing levels of voter turnout due to recently declining union membership come primarily from indirect mobilization rather than direct mobilization.

Experimental Investigation on Environmentally Sustainable Cement Composites Based on Wheat Straw and Perlite.

Environmentally sustainable cement mortars containing wheat straw (Southern Italy, Apulia region) of different length and dosage and perlite beads as aggregates were prepared and characterised by rheological, thermal, acoustic, mechanical, optical and microstructural tests. A complete replacement of the conventional sand was carried out. Composites with bare straw (S), perlite (P), and with a mixture of inorganic and organic aggregates (P/S), were characterised and compared with the properties of conventional sand mortar. It was observed that the straw fresh composites showed a decrease in workability with fibre length decrease and with increase in straw volume, while the conglomerates with bare perlite, and with the aggregate mixture, showed similar consistency to the control. The thermal insulation of the straw mortars was extremely high compared to the sand reference (85–90%), as was the acoustic absorption, especially in the 500–1000 Hz range. These results were attributed to the high porosity of these composites and showed enhancement of these properties with decrease in straw length and increase in straw volume. The bare perlite sample showed the lowest thermal insulation and acoustic absorption, being less porous than the former composites, while intermediate values were obtained with the P/S samples. The mechanical performance of the straw composites increased with length of the fibres and decreased with fibre dosage. The addition of expanded perlite to the mixture produced mortars with an improvement in mechanical strength and negligible modification of thermal properties. Straw mortars showed discrete cracks after failure, without separation of the two parts of the specimens, due to the aggregate tensile strength which influenced the impact compression tests. Preliminary observations of the stability of the mortars showed that, more than one year from preparation, the conglomerates did not show detectable signs of degradation.

Modeling soil aggregate fracture using the discrete element method

The Discrete Element Method (DEM) is a suitable approach for modeling and simulating arable soil and tillage processes. In this work, we focus on modeling soil fragmentation which is a vital element of many soil treatments. We present a method for computing the indirect tensile strength of soil aggregates through simulation. DEM aggregates are constructed as spherical clusters of smaller spherical particles. A number of indirect tensile tests are conducted using simulated aggregates from which the critical polar force and tensile strength are identified. We propose a method for introducing random voids such that the distribution of simulated tensile strength corresponds to a given Weibull distribution. We propose to scale the number of voids linearly with the measured porosity of the aggregates. This approach showed better performance than introducing a constant number of voids. We identified that the friction between the sub-spheres can be related to the characteristic strength and the number of voids is related to the spread of strengths in the Weibull distribution. The calibration and validation are performed on experimental data. Based on this approach, the synthetic DEM aggregates allow for deriving the aggregate strength as a function of aggregate size. The results are based on fracturing individual aggregates but can be extended to simulations involving multiple interacting aggregates.

Push-out bond strength of mineral trioxide aggregate with addition of titanium dioxide, silver, and silicon dioxide nanoparticles: An in vitro comparative study.

The ultimate goal of endodontic therapy is to eliminate all microorganisms present inside root canal and thereby sealing all the possible communicating pathways between pulpal and periradicular tissues, which prevents all the factors that cause recontamination and reinfection of the root canal system. If endodontic treatment fails, next approach is surgical endodontics. Bioceramics are recently introduced materials specifically designed for their potential use in medical field and dentistry. To evaluate and compare the push-out bond strength of mineral trioxide aggregate (MTA) by adding titanium dioxide (TiO2), silver, and silicon dioxide nanoparticles. Totally, 60 single-rooted human teeth were used. Middle third of the root was sectioned to obtain 2-mm thick root section. Acrylic was adapted to the section to obtain disks of 5 mm diameter and 2 mm thickness. Canal was prepared by GG Drill. Samples were divided into four groups of 15 each (n = 15): • Group I (control): MTA • Group II: MTA + TiO2 nanoparticles. • Group III: MTA + silver nanoparticles. • Group IV: MTA + silicon dioxide nanoparticles. The cement mixture was compacted into the canal. Samples were subjected to push-out bond strength using universal testing machine. The data were analyzed statistically by analysis of variance and post hoc comparison by Tukey's t-test. The highest push-out bond strength was shown by Group II (MTA with TiO2 nanoparticles), followed by Group III (MTA with silver nanoparticles) and Group I (MTA control group). The lowest push-out bond strength was shown by Group III (MTA with silicon dioxide nanoparticles). TiO2 and silver nanoparticles when added into MTA lead to an increase in push-out bond strength of MTA.

Feasibility Studies of Engineering Properties of Coarse Aggregates from Demolition Waste and Natural Aggregates for Road Construction

Construction and Demolition (C&D) waste constitutes a major portion of total solid waste origination in the world and most of it is used in landfills. The disposal of this construction and demolition waste is becoming a major concern as it is disposed unscientifically in India. The C&D waste is usually dumped on the sides of canals, minor roads and at the entrance of the cities and towns. This causes environmental problems and affects the quality of life of people. This paper discusses the possibility of replacing natural coarse aggregate with recycled concrete from demolition waste aggregate for road construction. Aggregate strength, gradation, absorption, specific gravity, shape and texture are some of the engineering properties that are desirable for road construction. Therefore, the experimental program was focused on the evaluation of engineering properties of the recycled aggregate over a period of 6 months. The findings from the study showed that the recycled concrete aggregate can be used for construction of transportation infrastructure. However, further research is needed particularly on the long term field performance of the recycled aggregate concrete before it can be used with confidence.

Response surface methodology approach for optimized compressive strength of some mix design concrete aggregates from waste cockle shells and glass powder

Nowadays, with increased demand for aggregates for concrete and an awareness of the need of protecting natural resources, experts are becoming increasingly interested in waste material as a building material substitute. However, the compressive strength is influenced by the composition of concrete. In this study, the compressive strength of concrete under substitution using waste from cockle shells and glass was investigated using Response Surface Methodology (RSM). Central Composite Design (CCD) based on RSM was used to assess the influence of epoxy resin, cockle shells powder, and glass powder on compressive strength responses. RSM developed first-order and second-order mathematical models with findings from experimental design. Analysis of variance was used to determine the correctness of CCD's mathematical models. Desirability analysis was then employed to optimize epoxy resin, cockle shells powder, and glass powder yielding maximum compressive strength. The RSM analysis revealed that the empirical results fit well into linear and quadratic models of concrete compressive strength. The mixing components will produce cement with compressive strength in each formulation of 54.71 MPa (4.88% epoxy resin and 4.0% cockle shells powder), 47.82 MPa (6.85% epoxy resin and 8.0% glass powder), 147.0 MPa, (4% cockle shells powder and 8% glass powder), and 56.08 MPa (4.4% epoxy resin, 4.0% cockle shells powder, and 8.0% glass powder). The results confirmed that a reasonable compressive strength of concrete could be achieved using epoxy resin, cockle shells powder, and glass powder.

Evaluation of antimicrobial action and push-out bond strength and compressive strength using mineral trioxide aggregate and triple antibiotic medicament combination as root-end filling material

Aim: The study aims to evaluate the antimicrobial properties and push-out bond and compressive strength of mineral trioxide aggregate (MTA) mixed with different ratios of triple antibiotic paste (TAP) against Enterococcus faecalis. Methodology: Antimicrobial effect was evaluated using agar well diffusion method. Materials were divided into three groups. Group 1: MTA, Group 2: MTA + TAP (2:1 ratio), and Group 3: MTA + TAP (1:1 ratio) zone of inhibition were determined after 24 h of incubation at 37°C. To evaluate push-out bond strength, 30 extracted teeth were decoronated to a length of 13 mm, followed by root canal treatment, the root resected at 3 mm from the apex, and root-end cavity was prepared and filled. Cylindrical specimens (n = 10 per group) of size 3 mm × 6 mm were prepared of MTA, MTA plus triple antibiotic 2:1 and 1:1 ratio and tested for compressive strength using Instron Universal testing machine. All the data were statistically analysed using Krusal–Wallis test (P < 0.05). Results: MTA + TAP (1:1 ratio) exhibited highest antimicrobial activity than MTA + TAP (2:1 ratio) and MTA alone. The push-out bond and compressive strength of Group 1 (MTA alone) was better compared to two groups containing MTA in combination with TAP; however, no statistical significant difference was found between the three groups. Conclusion: Combination of TAP with MTA increases the antimicrobial activity against E. faecalis without compromising much of the compressive and push-out bond strength, hence can be advocated for root-end filling.

Comparative evaluation of push-out bond strength of three retrograde filling materials in teeth with root apices resected at 90°: Mineral trioxide aggregate Angelus, Zirconomer, and Bioactive bone cement.

Surgical endodontic dissatisfaction is frequently caused by an inadequate seal at the apex. The retrograde filling material utilized should prevent any contaminants from seeping into the periradicular tissue. (1) To evaluate push-out bond strength of mineral trioxide aggregate (MTA) Angelus, Zirconomer, and Bioactive bone cement as root-end filling material, (2) To compare push-out bond strength of three different retrograde filling materials with a universal testing machine. At the cementoenamel junction, 36 removed upper anterior teeth were sliced horizontally. The samples were resected 3 mm at the apical end at a 90° angle along the long axis of the tooth, following the standard protocols. With an ultrasonic tip S12 90ND, a 3 mm root-end cavity was made. The teeth were then divided into three groups at random: Group 1: MTA Angelus, Group 2: Zirconomer, and Group 3: Bioactive bone cement. With the help of small pluggers, each material was compacted in the root-end cavity. Acrylic resin was used to embed the specimens. Each specimen's apical section was sliced into 2-mm thick slices perpendicular to the long axis. A universal testing equipment was used to apply a compressive push-out load, and the push-out bond strength was determined in megapascals. Zirconomer showed higher push-out bond strength when placed in the retrograde cavity preparation, followed by MTA Angelus and then Bioactive bone cement. Zirconomer showed superior resistance to dislodgment when compared to MTA Angelus, followed by Bioactive bone cement.

Effects of High-Volume Bottom Ash on Strength, Shrinkage, and Creep of High-Strength Recycled Concrete Aggregate

Effects of High-Volume Bottom Ash on Strength, Shrinkage, and Creep of High-Strength Recycled Concrete Aggregate

Evaluation of shear bond strength of e-mineral trioxide aggregate and biodentine with glass ionomer cement: An in vitro study

Aim: The aim of this study was to evaluate the shear bond strength of glass ionomer cement (GIC) with e-mineral trioxide aggregate (MTA) and Biodentine when placed immediately and after initial set.Materials and Methodology: Forty acrylic blocks with 2-mm height and 5-mm diameter central holes were prepared and randomly divided into two equal groups (n = 20). Group A (n = 20) and Group B (n = 20) were filled with E-MTA and Biodentine, respectively. These groups (n = 20) were further divided into two subgroups each; subgroup A1 (n = 10) and A2 (n = 10) were the placement of GIC immediately over freshly mixed e-MTA and after initial set e-MTA, respectively, subgroup B1 (n = 10) and B2 (n = 10) were the placement of GIC immediately over freshly mixed Biodentine and after initial set Biodentine, respectively. All the samples were later subjected to UTM for shear bond strength test.Results: The highest shear bond strength was recorded with subgroup B1 were the placement of GIC immediately over freshly mixed Biodentine, i. e., (18.72 MPa) and lowest with subgroup A2 placement of GIC after initial set MTA (5.96MPa). The shear bond strength of GIC condensed over freshly mixed e-MTA (subgroup A1) shows higher mean value then after initial set MTA (subgroup A2); however, SBS was highest in the placement of GIC immediately over freshly mixed Biodentine (subgroup B1).Conclusion: Within the limitation of this in vitro study, it can be concluded that freshly mixed Biodentine can be restored immediately with GIC.

An experimentation made on plastic and demolished waste in concrete mix

In the current experimental investigation, plastic waste is used as a partial substitute for fine aggregate to the extent of 10%, and coarse aggregate is partially replaced by destroyed material to the extent of 0%, 10%, 20%, 30%, 40%, and 50% of the total amount of coarse aggregate in the experiment. The standard mix for M25 grade concrete has been developed, with a water-to-cement ratio of 0.45. This proportion is employed in the concrete manufacturing process. During the course of this experiment, sixteen distinct combinations are created. The impact moulds used are 150 mm × 75 mm and the cubes used are 150 mm × 150 mm. The specimens used include cubes with dimensions of 1550 mm × 150 mm and cubes with dimensions of 300 mm × 300 mm. The density of concrete may be varied between 2500 and 2100 kg/m3 by replacing plastic garbage with sand at a constant percentage and modifying the replacement percentage of coarse aggregate with damaged material at a variable percentage. It was found that adding more recycled aggregate to fresh concrete made it less workable. According to the results, replacing natural sand and coarse aggregate in normal concrete with plastic waste and recycled aggregate increases compressive strength (fck) and split tensile strength (ft) by up to 10%, but then decreases when the quantity of recycled waste is increased. According to the findings of the experiment, fine aggregate replaced with 10% plastic waste and coarse aggregate replaced with 10% recycled aggregate resulted in excellent quality for new concrete as well as attaining the conventional concrete's goal mean strength.

Organic Farming Improves Soil Aggregation and Organic Carbon Status in the Rice-Wheat Cropping System in an Inceptisol

The paper deals with the long-term (11 yr.) impact of organic farming on soil aggregates and different forms of organic carbon namely, total, oxidizable and recalcitrant pools, and particulate organic matter-C in rice-wheat (R-W) and rice-wheat-mung bean (R-W-M) rotations in an Inceptisol. Soil aggregate stability (AS) was higher in R-W-M (86%) in the 0-7.5 cm layer than under R-W (83%). Organic nutrients resulted in 88-94% aggregate stability compared to 75% in the control (no nutrient supply). The R-W rotation recorded greater aggregate mean weight diameter (MWD) of 0.50 and 0.52 mm compared to 0.43 and 0.40 mm in R-W-M in 0-7.5 and 7.5-15 cm layer, respectively. The farmyard manure (FYM) with crop residues resulted in the highest total organic carbon (CTOC) content in both layers (1.88-2.05%). Large amounts of particulate organic matter-C (CPOM) were recorded in organic nutrient treatments as 0.4-0.5% in 0-7.5 cm compared to 0.3-0.4% in 7.5-15 cm layer. The MWD of aggregates correlated the best with CPOM (r=0.51) among the C pools, while AS showed the highest correlation with CTOC (r=0.53). The tensile strength of aggregates showed wide variability among the organic treatments and decreased with an increase in CTOC. An overall consideration of the results indicates that crop residue application with vermicompost or FYM has the most potent impact on soil physical condition and soil C status, holding a promise for sustaining the R-W cropping system in Inceptisol.

Analysis of the Aggregate Strength Variation along Different Sections of the River Basin

Analysis of the Aggregate Strength Variation along Different Sections of the River Basin

Study on Strength Enhancement Factors of Cement‐Stabilized Recycled Aggregate

With the rapid development and urbanization, huge amounts of construction and demolition (C & D) waste are produced. In order to protect the environment and conserve natural resources, promoting renewable materials, with C & D waste as raw materials, is imperative. However, the poor mechanical properties of recycled aggregate hinder its applicability in projects. In this study, two kinds of recycled aggregates, that is, concrete and brick slag, were strengthened with polyvinyl alcohol (PVA) solution, and the optimal strengthening time and soaking concentration were determined. Recycled mixed aggregate and brick slag were designed with two kinds of graded recycled aggregate. Recycled cement‐stabilized crushed stone specimens were prepared for a 7‐day unconfined compression and freeze‐thaw cycle test. The results showed that the recycled aggregate strength was improved to a certain extent, while the improvement of brick slag aggregate was more pronounced. The recycled mixture with less cement‐stabilized brick slag can be used for the base course of heavy traffic secondary highways before strengthening. Cement‐stabilized unreinforced brick slag has shown low strength, so it is not suitable to be used as a base on heavy traffic roads. The strengthened cement‐stabilized recycled mixture and cement‐stabilized brick slag could meet the requirements of heavy traffic class I and class II highways, respectively. When the cement grade, dosage, and grading type were kept the same, the strength of cement‐stabilized crushed stone prepared with larger aggregates was slightly lower. After the freeze‐thaw cyclic test, the strength loss of the recycled stable gravel was low, and its durability did not significantly improve after the reinforcement of recycled aggregate.

Distrontium Cerate as a Radiopaque Component of Hydraulic Endodontic Cement.

This study aimed to synthesize distrontium cerate (2SrO·CeO2: S2Ce) and evaluate its properties as an alternative component of the endodontic cement. S2Ce cement was prepared through calcination of strontium hydroxide and cerium carbonate. Subsequently, the crystal phase was confirmed using X-ray diffraction. S2Ce cement exhibited a rapid setting time (121 min) and achieved a high compressive strength (72.1 MPa) at 1 d after mixing, comparable to the compressive strength of a commercial mineral trioxide aggregate (MTA) cement (ProRoot MTA) after 28 d post mixing. However, the compressive strength decreased after 28 d of storage when the W/P ratio was 0.30–0.40 (p < 0.05). Ion dissolution test of the S2Ce cement showed that strontium ions were released after immersion in water (5.27 mg/mL after 1 d), whereas cerium dissolution was not detected. S2Ce exhibited approximately three times higher radiopacity (9.0 mm aluminum thickness equivalent) compared to the commercial MTA (p < 0.05). These findings suggest that S2Ce is a possible component for hydraulic endodontic cement that demonstrates a rapid setting and high radiopacity.

Compressive Strength of MICP-Treated Silica Sand with Different Particle Morphologies and Gradings

Microbially-induced calcium carbonate precipitation (MICP) can enhance the stiffness and bulk strength of sand aggregates via calcium carbonate cementation. This study explores the mechanical strength of silica sand aggregates with different particle morphologies and sizes following MICP treatment. Specifically, unconfined uniaxial compressive strength (UCS) of MICP-treated spherical, near-spherical, and angular aggregates are measured for four separate size fractions (18–25, 25–40, 40–60, and 60–80 mesh). Scanning electron microscope (SEM) imaging is performed on post-treatment samples to investigate the difference in cementation morphology and failure mechanisms. The experimental results indicate: (1) given identical cycles of MICP treatment, the UCS of treated spherical and near-spherical sands peaks at 25–40 mesh particle size, while the treated angular sands show increasing UCS with decreasing particle size; (2) spherical sands have the highest calcium carbonate (CaCO3) content given identical MICP cycles; and (3) higher post-treatment CaCO3 content does not correlate to higher UCS—implying that the distribution and morphology of CaCO3 precipitation exert crucial control. SEM analysis shows that CaCO3 fully encapsulates spherical sand particles uniformly, forming point contact bonds. In contrast, CaCO3 precipitations show a patchy distribution on near-spherical and angular sand grain surfaces. Unlike treated spherical sands, treated near-spherical sands feature a mixture of point and planar contact bonds while treated angular sands feature predominantly planar contact bonds. Planar contact bonds provide a larger effective cementation area between sand particles and thus result in higher bonding strength. The particle morphology and resultant inter-particle bonding morphology help reconcile higher ensemble UCS with lower CaCO3 content of treated angular sands.

Offsetting strength loss in concrete via ITZ enhancement: From the perspective of utilizing new alternative aggregate

In this work, the strength and microstructural changes in the interfacial transition zone (ITZ) of four individual concrete mixes containing four different materials (natural aggregate (NA), recycled concrete aggregate (RA), ceramsite (CA), and carbonated steel slag aggregate (SSA)) as 100% coarse aggregate replacement were investigated. The major takeaway from this work is the formation of better quality ITZ due to the use of carbonated SSA, as reflected by the higher microhardness and denser microstructure. The presence of calcite on the outer surface of SSA helps to form monocarbonate and serves as nucleation site for growth of calcium silicate hydrates, enabling a reduction in porosity and calcium hydroxide content by 56% and 80%, respectively compared to the NA concrete. As a result, SSA concrete achieved similar 28-day compressive strength as the NA concrete. This excitingly brings a new insight into how enhancement of the ITZ region could fully compensate the lower intrinsic strength of alternative aggregate used in the concrete.