Production Of Structural Concrete Research Articles

FEATURES OF USING CRUSHED CONCRETE AS A COARSE AGGREGATE FOR CONCRETE

Problem statement. According to the results of a study by the Kyiv School of Economics as of June 2023 the total amount of direct documented damage to residential and non-residential infrastructure due to destruction and damage as a result of military actions exceeded $150.5 billion. During the post-war reconstruction Ukraine will face the problem of a large number of buildings and structures that will be subject to partial dismantling and demolition. This process will be accompanied by the generation of a significant amount of construction waste, which traditionally in Ukraine is taken to landfills without recycling. On the other hand, there will be a need for a large quantity of construction materials, the share of which in the construction cost may reach 50 %. To reduce the cost of objects, it is advisable to reuse materials from waste generated after dismantling. Such materials are called recycling. The most obvious option is the use of crushed concrete waste as a coarse aggregate for the production of new concrete. The purpose of the article. Identification of the features of recycled coarse aggregates from concrete waste and concrete with their use, determination of the influence of source concrete on the properties of recycled aggregates. Conclusions. The mesoscopic model of concrete with recycled coarse aggregate has been examined. The analysis of the current research results on both recycled concrete aggregates and concrete with their use showed that, in general, with correct calculations of concrete mix compositions that consider the actual physical and mechanical properties of recycled aggregates, the production of structural concrete is possible. At the same time, crushing methods and the grain composition of such aggregates have a significant influence. In order to standardize the approaches to the research of recycled aggregates, it is necessary to create an appropriate methodology or regulatory framework.

A Review of Structures and Performance of Ternary Blends of Rice Husk Ash and Some Wastes in Concrete

The field of structural engineering has in recent times begun to widen its scope from the traditional analysis and design, into the development of new structural materials. This is because the use of non-renewable materials in forming and framing structural projects are raising serious environmental concerns bothering on sustainability of materials, especially cement, to produce structural concrete. Cement has been found to be a major contributor to greenhouse gases which affect the environment negatively. Waste from both the industrial and agricultural industries are gradually becoming sources of material to partly replace cement in concrete because of their pozzolanic properties. The agro-based pozzolanic materials include Rice husk Ash (RHA), Saw dust ash (SDA), Palm oil fuel ash (POFA) amongst others. To further widen the scope and resource base of pozzolanic materials for concreting, ternary blends consisting of agro-based pozzolans are being researched into. These research efforts however appear to be uncoordinated, and thus there is a need to juxtapose these efforts together to see the extent of work done on such ternary blends and present their relevant structural properties. This is with a view to helping identify gaps in such research as a means of preventing wastage of research energies. This paper presents a review of structural properties of some agro-based ternary blends used in structural concrete. It is concluded that more research effort is needed, especially in the development of practical and acceptable guidelines that will aid their application in concrete, for sustainable production of structural concrete.

Electric arc furnace slag in substitution of quartz for surface treatment of concrete paving slabs

Electric Arc Furnace (EAF) slag, a by-product of the steelmaking industry, also serves as a high-quality aggregate material for structural concrete production. In this research, its use is proposed as a Dry-Shake Hardener (DSH), in substitution of quartz, in concrete paving top coatings. Three concrete paving slab kinds were produced using EAF: one without fibers, another with metallic fibers; and the third with synthetic fibers. Half of each slab was coated with a classical cement-quartz mix and the other half with a novel cement-slag mix. After four years of outdoor aging at the city of Burgos, Spain, the slabs were visually inspected and no significant differences were found between the two coated materials. Impact, skid, and abrasion resistance tests were carried out and showed similar results for both types of coating courses. The result of both the short and long-term water absorption test results indicated, firstly, no short-term water absorption in both cases and, secondly, lower long-term water absorption in the quartz-cement mix. Finally, observation of the oil stain resistance tests on the top coatings led to the conclusion that the cleaning ability is very good. Analyzing all the results, it may be concluded that a new application for EAF slag have been found, it is a suitable material for use as a DSH for coating concrete paving slabs.

Performance and life cycle of ultra-high performance concrete mixes containing oil refinery waste catalyst and steel fibre recovered from scrap tyre

An economic solution to recycle spent equilibrium catalyst (Ecat) disposed of by petrochemical manufacturers and steel fibre recovered from scrap tyre would be their use in the production of structural concrete. In this study, the performance and life cycle of ultra-high performance concrete (UHPC) mixes containing these waste materials was examined. They were made using a total binder content of 1160 kg/m3 and also contained fly ash and silica fume in addition to Ecat and cement. Their average compressive strength at the end of 28 days was found to be above 150 MPa. The replacement of cement with Ecat reduced the CO2 emission and material cost of recycled steel fibre (RSF) reinforced UHPC samples by 15% and 6%, but there is no significant change in their compressive, flexural and split tensile strengths at the end of 28 days. Only 2% of the elastic modulus of these samples increased as a result of the addition of Ecat by weight of the binder. Ecat, an aluminosilicate material, is generally classified as a pozzolanic material, but its addition together with fly ash and silica fume in the UHPC mixture did not affect the strength gain properties. Based on our experimental findings, the use of waste materials including Ecat and RSF in the preparation of precast UHPC elements for explosion and earthquake resistant structures is recommended.

The effect of cement replacement with metakaolin and sugarcane bagasse ash as supplementary cementitious materials on the properties of concrete

The use of supplementary cementitious materials in the cement and construction industry is growing rapidly owing to the numerous benefits the application of these materials offers. In this study, the effects of metakaolin (MK) and sugarcane bagasse ash (SCBA) used to partially replace cement on concrete are investigated. The experimental plan was designed using a constant 5% MK and 0-20% SCBA contents by weight. The mix design of 1:2:3 and water-binder (w/b) ratio of 0.5 was employed. Samples prepared were tested at the ages of 7, 14, 28, and 60 days respectively. Concrete workability, water absorption, and densities all showed a decrease with an increase in the percentage of SCBA. The compressive strengths at lower percentages of SCBA (5% and 10%) recorded higher values compared to that of 5% MK and 0% SCBA. An increase in the percentage of SCBA above 10% however led to a decrease in compressive strength. The maximum compressive strength of 22.17N/mm2 was obtained at 60 days in concrete containing 5% MK and 10% SCBA. Both the T-statistics and F-statistics values calculated were statistically significant and exceeded their critical values. This suggests that there is a good relationship between the compressive strength of SCBA and the curing period and that the variation in the curing period and SCBA also causes a variation in the concrete compressive strength. From the results obtained, it is concluded that 5% MK and 10% SCBA can be applied to replace cement for structural concrete production.

Economical Assessment of Recycled Asphalt Pavement (RAP) Aggregate for Structural Concrete Production in Italy

Structural concrete aggregate can be substituted with sustainable alternatives from construction and demolition waste, such as reclaimed asphalt pavement (RAP). This contribution assesses the RAP aggregate production chain and aims to investigate the economic aspect of RAP aggregate, evaluating the costs associated with its production and comparing them with the ones necessary to produce NA and recycled concrete aggregate (RCA). This analysis aims to provide additional information on the possible advantages of RAP aggregate use in order to promote sustainable construction. The evaluation was developed using a four-step methodology consisting of (i) determining the RAP aggregate production procedure; (ii) selecting a case study; (iii) defining the mix design; and (iv) performing a cost evaluation and comparing it to the cost of NA and RCA production. The results of the cost analysis of three concretes containing different RAP percentages (0%, 30%, and 45%) demonstrated that RAP’s presence led to more expensive admixtures, with the RAP unit cost being higher than NA (+155.39%). Some strategies were proposed to diminish RAP’s cost, resulting in a reduction of −39.64% with respect to NA’s cost and ranging from 45.13% to 67.30% when compared to RCA’s cost.

Thermal Conductivity of Coconut Shell-Incorporated Concrete: A Systematic Assessment via Theory and Experiment

To minimize the energy consumption and adverse impact of excessive waste accumulation on the environment, coconut shell (CA) became a potential (partial) replacement agent for fine aggregates in structural concrete production. Thus, systematic experimental and theoretical studies are essential to determine the thermal and structural properties of such concrete containing optimum level of CA. In this view, an artificial neural network (ANN) model, gene expression programming (GEP) model, and response surface method (RS) were used to predict and optimize the desired engineering characteristics of some concrete mixes designed with various levels of CA inclusion. Furthermore, the proposed model’s performance was assessed in terms of different statistical parameters calculated using ANOVA. The results revealed that the proposed concrete mix made using 53% of CA as a partial replacement of fine aggregate achieved an optimum density of 2246 kg/m3 and thermal conductivity of 0.5952 W/mK, which was lower than the control specimen (0.79 W/mK). The p-value of the optimum concrete mix was less than 0.0001 and the F-value was over 147.47, indicating the significance of all models. It is asserted that ANN, GEP, and RSM are accurate and reliable, and can further be used to predict a strong structural–thermal correlation with minimal error. In brief, the specimen composed with 53% of CA as a replacement for fine aggregate may be beneficial to develop environmentally amiable green structural concrete.

Comparison of lightweight and normal-weight aggregate concrete

In this experimental study, lightweight aggregate concrete (LWAC) and normal-weight aggregate concrete (NWAC) were compared within the contexts of the size of calcium hydroxide (CH) crystals in interfacial transition zone (ITZ), compressive strength, and oven-dry density. Six LWAC and NWAC mixtures were prepared for this study. Thirty-six images obtained from Scanning Electron Microscope (SEM) were used to determine the size of CH crystals in ITZ of LWAC and NWAC. Eighteen test specimens (three for each of the six LWAC and NWAC mixtures) were prepared in 150x300 mm sizes and in the form of cylinders for the compressive strength tests and also eighteen test specimens in 100x100x100 mm sizes and in the form of cubes for the oven-dry density tests. It was determined that the size of CH crystals in ITZ of LWAC is 8.43% less than (on average), compressive strength of LWAC is 39.09% more than (on average), and oven-dry density of LWAC is 10.97% less than (on average) the NWAC’s that has the same volumetric proportions of ingredients. The findings of this study show that lightweight aggregate that has high particle density, angular shape, rough surface texture, and a structure that enables chemical reaction with CH crystals will be beneficial for the ITZ microstructure and properties of concrete. It is considered that these properties should be taken into consideration in the selection of lightweight aggregate for structural concrete production.

Optimization of axial load carrying capacity of CFST stub columns

Concrete filled steel tubular (CFST) columns are widely used due to their enhanced mechanical properties. The interaction between the concrete core and the steel casing increases structural stability and magnifies the compressive strength of concrete. Besides the structural performance, in alignment with the commitment of the concrete industry to reduce its environmental impact, lowering the carbon emissions caused by the production of concrete structures is gaining importance in recent years. The current paper gives an overview of the equations available in the literature that predict the axial load carrying capacity of rectangular CFST columns. A modified version of the Jaya metaheuristic algorithm is being proposed and the outcome of this algorithm is being presented. The algorithm is used in order to maximize the axial load-carrying capacity of a stub column. As an optimization constraint the CO2 emission associated with the production of the CFST column is being kept below a predefined level throughout the optimization process. The optimization process as well as the cross-sectional dimensions associated with the optimum solution are presented.

Effects of using pulverized termite mound (PTM) as partial replacement of fine aggregate on the durability properties and microstructure of concrete

The unrestrained use of non-renewable natural resources used in the production of structural concrete raises sustainability concerns. The use of appropriate waste and non-conventional materials is encouraged to address some of these concerns. Understanding the relationship between the durability properties and microstructure of such a material will increase innovation in its use and mitigate some of the environmental issues associated with concrete production. This paper presents the results of a study conducted to evaluate the durability and investigate the microstructure of concrete with fine aggregate partially replaced by pulverized termite mound (PTM). Durability was evaluated by sorptivity and water absorption coefficient tests. Scanning electron microscopy (SEM) was used to study the microstructure of the concrete specimens after 28 days of curing. The results show (i) that the durability of the PTM concrete specimens, as measured by the water absorption coefficient, improves progressively with PTM content, (ii) that the durability of the PTM specimens, as evaluated by sorptivity, improves up to a PTM content of 70%, and (iii) that the microstructure of the concrete specimens has smaller pores compared to the control, which follows the trend of the sorptivity results. Therefore, for practical purposes, the use of PTM mounds as a substitute for fine aggregate in the production of structural concrete should be limited to 70 %.

Impact of Length and Percent Dosage of Recycled Steel Fibers on the Mechanical Properties of Concrete

The global rapid increase in waste tyres accumulation, as well as the looming social and environmental concerns, have become major threats in recent times. The use of Recycled Steel Fiber (RSF) extracted from waste tyres in fiber reinforced concrete can be of great profitable engineering applications however the choice of suitable length and volume fractions of RSF is presently the key challenge that requires research exploration. The present experimental work aims at investigating the influence of varying lengths (7.62 and 10.16 cm) and dosages (1, 1.5, 2, 2.5, 3, 3.5, and 4%) of RSF on the various mechanical properties and durability of concrete. Test results revealed that the varying lengths and dosages of RSF significantly affect the mechanical properties of concrete. The improvements in the compressive strength, splitting tensile strength, and Modulus of Rupture (MOR) of RSF reinforced concrete observed were about 26, 70, and 63%, respectively. Moreover, the RSF reinforced concrete showed an increase of about 20 and 15% in the yield load and ultimate load-carrying capacity, respectively. The durability test results showed a greater loss in compressive strength and modulus of elasticity and a smaller loss in concrete mass of SFRC. Based on the experimental findings of this study, the optimum dosages of RSF as 2.5 and 2% for the lengths 7.62 and 10.16 cm lengths, respectively are recommended for production of structural concrete. Doi: 10.28991/cej-2021-03091750 Full Text: PDF

Feasibility of using industrial boiler ash in the dosing of structural concrete

Industrialization and accelerated population growth generate side effects on various social aspects, and the environmental issue is worrisome due to the impacts caused by social evolution. The management of industrial waste is a great challenge that involves both control of its generation and the proper disposal, ensuring environmental sustainability. Boiler ash residue is found in abundance in factories that use this equipment for steam generation. This abundance occurs due to the lack of a place for proper disposal or reuse of the residue. In view of this scenario, this article had as a guide question: Would it be possible to use this residue in the production of structural concrete? The aim of this study was to classify the residue by defining its possible form of use in concrete dosage and to perform experimental dosages with the use of industrial boiler ash to evaluate its possible technical contributions to basic properties of concrete. For this, samples were collected by an industry installed in the city of Uberlândia, State of Minas Gerais, active in several sectors such as agriculture, animal nutrition, pharmaceutical and others. The classification of boiler ash was performed by applying the Brazilian normative procedures and parameters used for classification of binders and aggregates for concrete. Considering its granulometric curve and density, the residue was classified as light and very thin aggregate, thus adopting the methodology of partial replacement of the thin aggregate by boiler ash. It was verified that there was a reduction in the workability of concrete in the fresh state proportionally to the residue content used. Therefore, it is necessary to use superplasticizer additives in these cases to maintain the expected workability. A reduction in the density of concrete was noticed when the residue was used, considering as necessary the attention to this property of the concrete in relation to the content used of the residue in the dosage. It was also observed when comparing the dosages with the use of the residue at the standard dosage, that there was a reduction in compressive strength. However, there was no great variation in compressive strength between the dosages with different substitution levels used. It was concluded, therefore, considering the levels used in this study, as feasible the use of this residue in the production of structural concrete.

Production and properties of lightweight concrete incorporating recycled waste crushed clay bricks

The huge amount of waste crushed clay bricks (CCB) causes serious environmental problems worldwide. To deal with this issue and preserve natural resources, CCB can be recycled and reused in the concrete industry. This paper investigated the influence of CCB as substitution of cement and aggregates on the physical, mechanical, and microstructural properties of concrete. Eight mixtures were prepared and tested to find out the possibility of reusing CCB as aggregate and as cementitious material for structural concrete production. Several experiments have been performed to assess the performance of the concrete. Concrete workability was assessed by measuring the slump of fresh concrete. For hardened properties evaluation, dry density, compressive strength, ultrasonic pulse velocity, porosity, thermal conductivity, water penetration test, and sorptivity tests have been investigated. In addition, scanning electron microscopy, X-ray diffraction, and thermo-gravimetric analysis were implemented to analyze the morphology and microstructure characteristics of concrete. The experimental results indicated that CCB can be reutilized as a replacement of normal-weight aggregates to obtain structural lightweight aggregate concrete with appropriate properties. It was also proved that grinded CCB has a proper pozzolanic activity and can be used as supplementary cementitious material to reduce cement content without significant deterioration of concrete properties.

A Review of Some Agricultural Wastes in Nigeria for Sustainability in the Production of Structural Concrete

A review of agricultural wastes available in Nigeria that is suitable for use in concrete industry, in order to attain sustainability in structural concrete production and practice, is presented in this paper. The wastes reviewed are: Cassava Peel Ash (CPA), Empty Palm Oil Fruit Brunch Ash (EPO-FBA), Rice Husk Ash (RHA), and Saw Dust Ash (SDA). Others were Palm Kernel Shell Ash (PKSA), Groundnut Husk Ash (GHA), Corncob Ash (CA), and Egg Shell Powder (ESP). The study revealed that some agricultural wastes that have potential for use as supplementary cementing material (SCM) for cement in the production of structural concrete abounds in Nigeria. It was also revealed that the necessity of standardization of procedures for testing of such wastes so that structural performance index can be compared. In addition, there is also the need for the development of classification methods similar to that of fly ash, so that their use can be enhanced. Using these waste materials in concrete will lead to sustainability in concrete production, reduction in the use of natural non-renewable resources, innovativeness in the use of wastes, and the development of small-scale industries.

Workability, strength, and microstructure of high strength sustainable concrete incorporating recycled clay brick aggregate and calcined clay

Abstract This study examines the workability, strength, and microstructure of high strength eco-concrete incorporating recycled clay brick aggregate and calcined clay. The study adopted a design mixes proportioning of 1:1:2 by weight at a constant water/binder ratio of 0.25. The waste bricks were crushed, then used to partially substitute sand at levels of 0, 10, 20, 30, 40, and 50%, while calcined clay was used as a pozzolanic supplement was blended with cement at a constant replacement dosage of 10%. The workability was determined using the slump apparatus. The compressive, split tensile and flexural strengths of the hardened samples were evaluated using cubes, cylinders and beams of dimension 100 mm3, 100 × 200 mm and 100 x 100 × 550 mm, respectively. Scanning electron microscopy (SEM) coupled with energy dispersive x-ray (EDX) was conducted on selected samples. Results from the tests indicated a decreasing trend in the workability as the recycled clay brick content increases. Results on the mechanical properties show some levels of improvement in the strength performance and microstructure of the hardened samples containing recycled clay brick aggregate, not beyond 30% at constant calcined clay content. Concrete mix with 10% recycled clay brick aggregate and 10% calcined clay achieved a higher strength compared to the control. This implies that recycled clay brick aggregate can be utilize in the production of structural concrete.

Waste of Civil Construction for Use in Mortar and Production of Structural Concrete

Civil construction is a sector of extreme impact on the Brazilian economy, both in terms of jobs as well as consumption of raw material and waste generation. Civil construction waste (CCW) represents a large part of the total mass of municipal solid waste in a medium and large city. An alternative to diminish these released wastes is to reuse them. In this work, a study was carried out using CCW both to produce concrete with sand substitution and as a small aggregate for use in mortar. The compression strength of structural concrete and mortar, with total and partial replacement of sand, was analyzed. In addition, the consistency of mortar with the replacing was also studied. The results of the compression test indicate superior quality for concretes (75wt% CCW) and mortar with CCW incorporation. The required amount of water for good workability in the modified mortar is 310 g, against 270 g for the reference mortar.

Use of ornamental rock waste as a partial substitute for binder in the production of structural concrete

Abstract Due to the population increase, to the improvement of life conditions, to the elevation of levels of consumption and the growing industrialization of developing countries, it is estimated that the production of concrete will present significant increase in the next decades. The process of producing cement is responsible for approximately 5 % of the emissions of CO2, an expressive environment pollutant. In this context, this work presents an evaluation of the influence of partial substitution of cement by ornamental rock waste (ORW) on the physical and mechanical properties of concrete. ORW from a local marble and granite processing company was used. The waste was mineralogically characterized through X-ray diffraction (XRD) essays, energy-dispersive X-ray (EDX) microanalysis, and physically characterized through laser granulometry and specific mass. For this, was adopted a concrete trace as reference, produced with CP V-ARI cement (similar to ASTM Type III), from IPT dosage. Waste was used in proportions of 5 %, 7.5 %, 10 % and 12.5 % of substitution of cement by mass. Results were treated with ANOVA and multiple comparison of means, indicating a possibility of substitution of until 10% of cement by ORW, creating a concrete with proper resistance to Brazilian regulations regarding the classification as structural.

Sustainable alternative aggregates: Characterization and influence on mechanical behavior of basalt fiber reinforced concrete

Demands to assess the feasibility of utilizing alternative sustainable aggregates in concrete have been raised because of the rapid depletion of virgin aggregates resources. In this study, a comparison of the physio-chemical properties of commonly used natural gabbro aggregates (NGA) and natural limestone aggregates (NLA) and their possible sustainable alternatives recycled concrete aggregates (RCA) and steel slag aggregates (SSA) is presented. The suitability of these alternate aggregates is assessed through several standardized tests. Chemical compositions, mineralogical and morphological properties of these aggregates are also reported. To determine the possible leachates of hazardous metals into the environment when used as concrete aggregates, the inductively coupled-plasma atomic emission spectroscopy was carried out on acid digestions of these aggregates. Additionally, basalt macro-fibers (BMF) were incorporated to improve the mechanical properties of concrete made with RCA and local NLA which are deemed as weak and unfit for use as aggregates in structural concrete. Experimental results revealed that both RCA and SSA could be used as sustainable alternative aggregates to have a cleaner production of structural concrete. They had acceptable leachate limits of the hazardous elements. The soundness test results and expansion under autoclave of SSA were well below the acceptable limits. The concrete made with SSA showed higher mechanical properties than the concretes made with other aggregate types. As expected, BMF improved the mechanical properties of concrete made with the low-strength NLA and RCA.

Effect of compression casting method on the compressive strength, elastic modulus and microstructure of rubber concrete

Recycling rubber in the production of structural concrete is not considered a feasible option due to a significant reduction in the strength and elastic modulus of concrete. A novel concrete casting method is developed in this work that can greatly increase the strength and elastic modulus of rubber concrete. The mix design used in the study is the same as that for natural aggregate concrete (NAC), apart from replacing some of the natural coarse aggregate (NCA) by chipped rubber. Concrete specimens were cast with 0–100% chipped rubber in replacement of NCA. The fresh rubber concrete was then condensed in a specially designed mold to compress the volume of wet concrete for a period of time before demolding. Stress-strain behaviour of compressed and uncompressed rubber concrete specimens was evaluated and compared with the NAC specimens. Results show that improved stress-strain behaviour i.e., higher compressive strength and elastic modulus, are observed for compressed rubber concrete specimens as compared with uncompressed specimens, which show the effectiveness of the compression technique in enhancing the performance of rubber concrete. Compressed rubber concrete specimens with a 20% replacement ratio of chipped rubber show 35% and 29% increase in strength and elastic modulus as compared with NAC specimens, respectively. Based on the results, up to 30% of NCA can be replaced by chipped rubber to obtain compressed rubber concrete with the compressive strength and elastic modulus greater or similar to those of NAC. The proposed method encourages the utilization of waste rubber in concrete and can be easily adopted by the precast industry to manufacture precast concrete products leading towards sustainable and environment-friendly construction.

Properties of concrete with the addition of copper slag aggregate

Recently, the demand for various types of aggregates in Poland has been very significant. The resources of natural aggregates are shrinking and their exploitation has a large environmental impact. Recycled and artificial aggregates, including copper slag aggregates, are therefore increasingly used in road and railway construction as well as in general construction works. The paper presents the results of experimental research concerning the possibility of using copper slag aggregates for the production of structural concretes which, apart from their adequate compressive strength, were resistant to atmospheric conditions and thus could be used in bridges, roads, or other objects exposed to such special conditions. In the conducted research, the physical and mechanical characteristics of the materials included in the concrete were assessed, but the main emphasis was put on the research on the influence of the quantity of copper slag aggregates on the basic properties of concrete such as: compressive strength, water absorption, and freeze-thaw durability. The results of the research showed that copper aggregate can successfully replace natural aggregate in cement concretes. The copper slag aggregate showed better properties than the granite aggregate used in the reference concrete. All the concretes tested after 28 days met the concrete strength requirements. For the concretes with a copper slag aggregate content of 25% and 50% there was a few percent increase in compressive strength. On the other hand, for the concretes with 75% and 100% of the copper slag aggregate, compression strength drops of up to 14% were recorded. The water absorption of the reference concrete was worse than that of all the concretes containing copper slag aggregates. Both the reference concrete and all the concretes with copper slag aggregate meet the requirements for freeze-thaw durability grade F150. Concretes with copper slag aggregate subjected to 150 freezing and thawing cycles exhibit a compression strength drop of up to 4%.