Ground Granulated Blast Furnace Slag Concrete Research Articles

Environmental Life Cycle Assessment of Alkali-activated Material with Different Mix Designs and Self-healing Agents

Alternative low-carbon cementitious binders such as geopolymers are rapidly garnering scientific interest to replace Ordinary Portland Cement (OPC). Industrial waste by-products such as coal fly ash (CFA) and ground granulated blast furnace slag (GGBS) are usually utilized for this material. Microcapsules can also be added to geopolymers to enhance its self-healing capability as it has potential environmental benefits aside from cost savings. This study thus focuses on the cradle-to-gate LCA of geopolymer concrete containing microcapsules for self-healing. Two different microcapsules were considered: Urea-formaldehyde (UF)/Dicyclopentadiene (DCPD) and Poly(urea-urethane) (PUU)/Alkali-activator (AA). Three different geopolymer precursors were studied: CFA, GGBS and CFA/GGBS. OpenLCA software was used for the calculations and analysis, and the inventory data were obtained from Ecoinvent and OzLCI2019 supplemented by literature data. An impact assessment was carried out using CML 2001. Self-healing geopolymer concrete is better in terms of lower global warming potential but performs worse in other impact categories than conventional OPC concrete. Of the geopolymer concrete assessed, GGBS concrete has the lowest impacts. On the other hand, of the two self-healing microcapsules, UF/DCPD is better for the environment. The primary factor for this difference is the solvent used in microcapsule synthesis. From this result, it has been shown that self-healing GGBS concrete containing UF/DCPD microcapsules has the lowest impacts of the self-healing concrete assessed.

Influence of the environmental relative humidity on carbonation behavior of cracked PC, FA and GGBS concretes

In this study, based on the accelerated carbonation test results on unloaded 100-mm cubes and loaded RC beams, where test specimens were made with three types of concretes, i.e., Portland cement (PC) concrete, PC with 30% of fly ash (FA) and PC with 50% of ground granulated blast-furnace slag (GGBS), an analytical model was proposed to predict the carbonation depth of the in-service RC elements made from concretes similar to those in the accelerated tests. It is concluded that, in general, for those real RC elements with different types and water-binder ratios (w/b), the trend of the predicted carbonation depths first increases and then decreases with the increase of the relative humidity (RH) in typical design working life of 50 years. Under different environmental relative humidity, for loaded RC elements, only Portland cement concrete and concrete GGBS with lower w/b meet the durability requirements of the different exposure environments in 50-year design working life. The maximum predicted carbonation depths of various types of concretes are observed in the range of 50-70% relative humidity and the ‘green’ FA and GGBS concretes with larger w/b can not meet the durability requirements of the exposure environments in this relative humidity range when they were subjected to in-service loads.

Pore Size Distribution and Surface Multifractal Dimension by Multicycle Mercury Intrusion Porosimetry of GGBFS and Limestone Powder Blended Concrete

Eco-friendly concrete mixtures make efficient use of constituents with reduced environmental impact to secure durable structures. Ternary mixes containing Portland cement, ground granulated blast-furnace slag (GGBFS) and limestone powder (LP) have demonstrated a good balance between environmental impact, economic cost and technical performance. The pore structure of cement-based materials determines the transport of species; hence its description is a valuable tool for predicting their durability performance. In this paper, textural analysis of the pore structure of Portland cement concrete and GGBFS and limestone powder blended concrete is assessed by multicycle mercury intrusion porosimetry (MIP). Results from three intrusion-extrusion cycles were used for determining pore volume, size distribution and surface multifractal dimension. The hysteresis during the experiments is mainly explained by the combined effects of ink-bottle pores and different contact angles for the intrusion and retraction. The analysis of the surface multifractal dimension of the pore structure showed no significant effects of GGBFS and limestone powder on the pore wall texture of concrete samples. The outcome depicts the advantages of using multiple intrusion-extrusion cycles during MIP experiments, as well as the effect of 35 wt.% GGBFS, 25 wt.% GGBFS + 10 wt.% LP, and 25 wt.% of LP, on concrete pore structure.

Evaluation of graded layer in ground granulated blast furnace slag based layered concrete

This paper reports on the generation, properties, and spatial variability of the graded layer in functionally graded concrete (FGC) made using 20, 35, and 50% ground granulated blast furnace slag (GGBFS) as partial replacement of ordinary Portland cement (OPC). Two different layers of concrete, one being OPC based normal concrete and the other being GGBFS blended concrete were used to prepare the FGC specimens. The control concrete specimens were made with a single layer OPC or GGBFS concrete. Excluding the control concrete samples, three types of double-layered cube samples of 150 mm thick were prepared in various combinations of the thickness of constituent layers. These double-layered combinations were 25 mm + 125 mm, 75 mm + 75 mm, and 125 mm + 25 mm thick containing OPC concrete and GGBFS blended concrete respectively. The properties like compressive strength, the interfacial bond between two constituent layers, modulus of elasticity, micro-structure, and graded layer were examined. The formation, thickness, and properties of the graded layer at the interface of constituent layers were evaluated using elastic equations and microstructural studies like scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The investigation was conducted by applying the load parallel and perpendicular to the interface plane between constituent layers. The results showed that the properties of concrete improved in FGC compared to control. Formation of graded layer added value to the FGC. Among the specimens of various thickness combinations, the samples with 75 mm OPC concrete and 75 mm GGBFS concrete showed the best results when the load was applied parallel to the graded layer. Finally, environmental benefit in terms of embodied CO2, energy and cost benefit of the different mix proportion concrete are analysed. Further the effectiveness of FGC is also reported which has huge potential to be used in concrete structure elements.

Strength and durability of fiber reinforced concrete with partial replacement of cement by Ground Granulated Blast Furnace Slag

Concrete is a widely used construction material all over the world, with approximately six billion tons has been delivered every year. In the production of cement clinker, approximately one ton of CO2 has been released for one ton of cement. Cement use must be reduced by using substitute products to minimise CO2 emissions. To reduce the pollution and economy of construction industry cement is replaced by by-products to enhance its strength parameters. Our research work deals with the study of mechanical and durability properties of concrete. To assess the efficiency of Ground Granulated Blast Furnace Slag (GGBS) as a partial substitute for cement and to improve the tensile and flexural strengths and serviceability of concrete, all tests are carried out according to Indian standard codes. Various concrete mixes were planned with partial replacement of cement by GGBS in different proportions (0%, 20%, 40%, 60% and 80%) for a cement content of 400 kg/m3, with W/B ratio of 0.5, and steel fibers having an aspect ratio of 60 with three volume fractions (0.5%, 1% and 1.5%) .At the ages of 28, 90, and 180 days, concrete specimens were cast and investigations were carried out to determine the strength variations of concrete with and without fibers. Durability studies like water absorption, sorptivity, Rapid Chloride ion Penetration Test (RCPT) were done on GGBS concrete without fibers at 28 and 180 days. By replacing of cement with GGBS in concrete upto 40% increases the compressive strength of concrete by about 5–20%. Steel fibres increase the split tensile and flexural strength of concrete by considerable amount. A significant increase of split tensile flexural strengths of Steel Fiber Reinforced Concrete (SFRC) which ranged from 19 to 65% and 18–74% respectively, increase in strength was compared with conventional concrete without fibers of 28 to 180 days. A remarkable reduction has been observed in RCPT, sorptivity, and water absorption values when the cement was partially replaced by GGBS at 80% than conventional concrete.

Experimental research of hybrid fibers based Geo-polymer concrete

In development enterprises, concrete is regularly utilized material. For the creation of concrete, development industry utilizes a large portion of the regular assets. During the creation of concrete, carbon dioxide is delivered which may prompts ozone harming substance emanation impact. For this geopolymer concrete has been found for the substitute to the OPC. It utilizes mechanical waste material, for example, fly debris, GGBS, rather than concrete, there by diminishing effects because of concrete. Ground Granulated Blast furnace Slag (GGBS) is a by-product from steel industry. It has good structural and durable properties with less environmental effects. This paper critically reviews the literatures available on GGBS used in cement concrete. The utilization of supplementary cementitious materials is well accepted because of the several improvements possible in the concrete composites and due to the overall economy. The present paper is an effort to quantify the 28-day cementitious efficiency of ground granulated blast furnace slag (GGBS) in concrete at the various replacement levels. It was observed that this overall strength efficiency of GGBS concretes can also be defined through a procedure adopted earlier for other cementitious materials like fly ash and silica fume. Fly debris and GGBS are the covers which respond with basic arrangement like Na2SiO3 and NaOH and structure a gel which effectively ties with fine total and coarse total. Strands are added to the geo polymer concrete in the scope of 0.1%, 0.2%, 0.3%, 0.4% and 0.5% at 0.1% increases. In this examination, different rates of basalt strands, AR glass filaments and polypropylene filaments are added to the geo polymer concrete and the compressive, flexural and split elasticity of various blends were contrasted and geo polymer concrete, to know the quality of shapes, chambers and pillars. In this task, indicated that the more retarder added, the setting season of geo polymer solid will be expanded, subsequently expanding its functionality.

Influence of in-situ casting temperature and curing regime on the properties of blended cement concretes under hot climatic conditions

Casting temperature and curing method significantly affect the properties of concrete, especially the blended cement concretes. Consequently, it is imperative to study the influence of casting temperature and curing regime on the properties of concretes. This paper reports results of a study conducted to evaluate the properties of plain and blended cement concretes prepared using very fine fly ash (VFFA), fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBFS) and natural pozzolan (NP) cast and cured under varying temperature and curing conditions. The concrete specimens were prepared under natural summer atmosphere at intital concrete temperature of 25, 32, 38 or 45 °C. The specimens were cured under laboratory conditions by water ponding and under hot weaterher conditions by covering with wet burlap or applying a curing compound. The effect of casting temperature and curing regime on the properties of the studied concretes was evaluated by measuring compressive and split tensile strength up to 180 days, pulse velocity up to 90 days and depth of water penetration after 28 days of curing. As expected, the properties of concrete specimens cured by water ponding were better than those cured by covering with wet burlap or applying a curing compound. The properties of blended cement concretes were better than those of plain cement concretes at later ages due to the pozzolanic reaction. It is postulated that the optimum casting temperature is 32 °C for OPC and SF cement concretes while it is 38 °C for VFFA, FA, GGBFS and NP cement concretes. This finding differs with the current international practice of limiting the casting temperature to 35 °C.

Sustainable natural pozzolana concrete – A comparative study on its environmental performance against concretes with other industrial by-products

With increasing environmental sustainability concerns in the construction industry and a demand for producing more durable and sustainable concrete, effort is devoted to producing concrete with Ordinary Portland cement (OPC) being substituted by alternative binder materials. By considering the compressive strength, the comprehensive environmental performance of natural pozzolana in concrete was evaluated comparatively by developing six mix-designs of concrete with OPC, and commonly used industrial by-products as supplementary cementitious materials such as fly ash (FA) and ground granulated blast furnace slag (GGBS) based on the lifecycle assessment (LCA) approach. The results show that comparable compressive strengths can be achieved for the use of 20% and 30% volcanic ash (VA) against conventional SCMs. Using the volume as functional unit, the LCA results have demonstrated that higher environmental savings are associated with VA concrete compared to that of OPC, GGBS (30%) and FA (25%), but almost similar when 50% GGBS is used. For example, 15–24% and 10–19% lower global warming potential are associated with VA concretes compared to that of OPC and FA concretes, respectively, but much higher saving is found when considering the strength of the concrete, as they are about 11–12%, 10–11% and 29–30% compared to that of GGBS, FA and OPC concretes, respectively. The results can be used as valuable guidelines for VA-based in sustainable concrete production, which would further enhance the sustainability of the concrete industry.

Service life of GGBFS concrete under carbonation through probabilistic method considering cold joint and tensile stress

Carbonation is a typical deterioration phenomenon which accelerates steel corrosion through pH drop in pore water by intrusion of external carbon dioxide (CO2). Many researches have been performed on carbonation process considering carbonic reaction, mixture conditions, and exterior conditions. Recently probabilistic approaches have been adopted for considering engineering uncertainties such as complicated material behavior, simple evaluation system, and limited sample numbers. In the study, the service life variation was evaluated considering several effects of induced tensile stress level, cold joint, and GGBFS (Ground Granulated Blast Furnace Slag) through probabilistic approach. Utilizing the previous test results, the effect of loading conditions on carbonation depth was investigated. Four design parameters like cover depth, exterior CO2 concentration, carbonatable material, and CO2 diffusion coefficient were assumed as random variables for probability analysis. Through MCS (Monte Carlo Simulation) with normal distributions and intended PDF (Probability of Durability Failure) of 10%, variations of service life were simulated for the RC structure under loading conditions. The effects of COVs (Coefficient of Variation) for design parameters were also simulated. The comparisons of the predicted service life from the probabilistic and deterministic methods were quantitatively discussed, and the safety index with service life was also investigated. The results of this study can provide useful information on maintenance priority and service life evaluation for RC structures containing cold joint subjected to tensile stress.

Applicability of fib model code’s maturity function for estimating the strength development of GGBS concretes

The early age compressive strength of concrete can, according to the fib Model Code, be estimated from its 28-day strength using an exponential function. This requires an “s” value which depends on the strength class of the cement. This has recently been extended to include supplementary cementitious materials (SCMs), or otherwise known as additions, by providing a way of determining an appropriate “s” value based, in addition to cement strength class, on the water/binder and SCM/binder ratio. The applicability of this relationship for four concrete grades (C30/37, C35/45, C50/60 and C60/75) with up to 70% ground granulated blast-furnace slag (GGBS) has been investigated and shown to be satisfactory. This increased confidence in its use for predicting the strength development of other curing regimes, i.e. adiabatically cured concrete cubes, using the maturity function in the fib Model Code. Predictions/estimates of the effect of the adiabatic temperature history on the compressive strength development using the maturity function in the fib Model Code have been compared to those of the Arrhenius function that uses a strength-time relationship and “apparent” activation energy determined from experimental data. The fib Model Code’s strength estimates were not significantly affected by the use of one value of “apparent” activation energy for all concrete mixes, i.e. the “apparent” activation energy was not specific to the concrete mix.

The determination of ground granulated concrete compressive strength based machine learning models

The advancement of machine learning (ML) models has received remarkable attention by several science and engineering applications. Within the material engineering, ML models are usually utilized for building an expert system for supporting material design and attaining an optimal formulation material sustainability and maintenance. The current study is conducted on the based of the utilization of ML models for modeling compressive strength (Cs) of ground granulated blast furnace slag concrete (GGBFSC). Random Forest (RF) model is developed for this purpose. The predictive model is constructed based on multiple correlated properties for the concrete material including coarse aggregate (CA), curing temperature (T), GGBFSC to total binder ratio (GGBFSC/B), water to binder ratio (w/b), water content (W), fine aggregate (FA), superplasticizer (SP). A total of 268 experimental dataset are gather form the open-source previous published researches, are used to build the predictive model. For the verification purpose, a predominant ML model called support vector machine (SVM) is developed. The efficiency of the proposed predictive and the benchmark models is evaluated using statistical formulations and graphical presentation. Based on the attained prediction accuracy, RF model demonstrated an excellent performance for predicting the Cs using limited input parameters. Overall, the proposed methodology showed an exceptional predictive model that can be utilized for modeling compressive strength of GGBFSC.

Durability and Engineering Performance Evaluation of CaO Content and Ratio of Binary Blended Concrete Containing Ground Granulated Blast-Furnace Slag

This study aimed to evaluate the durability and engineering performance of concrete mixed with locally produced ground granulated blast-furnace slag (GGBS) based on CaO content and ratio, and to derive the optimal CaO content range that can secure durability. Hence, tests were conducted by increasing the GGBS replacement ratio by 10% from 0% to 70%, while the unit binder weight was fixed at 330 kg/m3. The results indicated that the compressive strength exhibited a tendency to increase when the CaO content and basicity increased within 28 d of age, although similar compressive strength characteristics were observed at 56 d of age, irrespective of the CaO content and basicity. Additionally, four test items (i.e., carbonation depth, chloride penetration depth, relative dynamic elastic modulus, and weight reducing ratio) were measured to evaluate durability. The optimal CaO content satisfying all four parameters was observed as ranging between 53% and 56% (GGBS replacement ratio: 27.5%–47.1%). The results of the study can provide guidelines on the mixing proportions of GGBS concrete with excellent durability that can be applied to local construction sites and can be used as basic data to set chemical composition criteria for the development of binders to improve durability.

Effect of temperature rise against durability and behaviour of ground granulated blast furnace slag concrete

Concrete which affected with high temperature will lost its strength significantly by 60%. To overcome this problem is utilizing steel industry waste, that is Ground Granulated Blast Furnace Slag (GGBFS) which is used as a substitute for cement in concrete mixtures. The properties of GGBFS which is cementitious same as cement, so that it can fulfil the function of cement. In this research, GGBFS concrete and normal concrete with strength of concrete is 30 Mpa and both types of concrete will be burned at a temperature of 600°C for 2 hours. After that, characteristics strength of concrete will be tested to GGBFS concrete and normal concrete in each concrete before being burned and after being burned. The result of this research, there was an insignificant increase in strength of concrete with GGBFS as a substitute for cement by 40%. The average compressive strength of GGBFS concrete before and after being burned was 30.48 MPa and 11.16 MPa, compared to normal concrete which was 30.06 MPa and 9.76 MPa. Increasing also happened at the result of flexural test, wich is initial crack at GGBFS concrete occur in greater deflection and load than normal concrete.

Evaluation of Strength Development in Concrete with Ground Granulated Blast Furnace Slag Using Apparent Activation Energy.

Ground granulated blast furnace slag (GGBFS) conventionally has been incorporated with ordinary Portland cement (OPC) owing to reduce the environmental load and enhance the engineering performance. Concrete with GGBFS shows different strength development of normal concrete, but sensitive, to exterior condition. Thus, a precise strength evaluation technique based on a quantitative model like full maturity model is required. Many studies have been performed on strength development of the concrete using equivalent age which is based on the apparent activation energy. In this process, it considers the effect of time and temperature simultaneously. However, the previous models on the apparent activation energy of concrete with mineral admixtures have limitation, and they have not considered the effect of temperature on strength development. In this paper, the apparent activation energy with GGBFS replacement ratio was calculated through several experiments and used to predict the compressive strength of GGBFS concrete. Concrete and mortar specimens with 0.6 water/binder ratio, and 0 to 60% GGBFS replacement were prepared. The apparent activation energy (Ea) was experimentally derived considering three different curing temperatures. Thermodynamic reactivity of GGBFS mixed concrete at different curing temperature was applied to evaluate the compressive strength model, and the experimental results were in good agreement with the model. The results show that when GGBFS replacement ratio was increased, there was a delay in compressive strength.

Axial performance of GGBFS concrete filled steel tubes

Fifteen circular concrete-filled-steel tubes (CFST) containing ground granulated blast furnace slag (GGBFS) concretes were tested in axial compression. CFST columns were casted with four concrete mixtures having 0, 15, 25 and 35% GGBFS replacement levels and two different length-to-diameter ratio of 2.87 and 4. Compressive strength for concrete mixtures was determined after 28, 56 and 90 days. Time-dependent compressive strengths of GGBFS concretes were also compared with those predicted by the equation of MC-10. Axial capacities of GGBFS concrete CFSTs were found to be more than those of control concrete CFSTs. Increase in axial capacity of CFSTs was proportional to the increase in compressive strength of concrete mixtures due to the inclusion of GGBFS. Stiffness of GGBFS concrete CFSTs were similar to those of control concrete CFSTs. Experimental axial capacities of CFST columns tested were also compared with the provisions of Architectural Institute of Japan (AIJ), ACI 318, Chinese code (DL/T) and EC 4. ACI 318 was found to be most over conservative followed by AIJ for the estimation of axial capacities of GGBFS concrete CFST columns. EC 4 and DL/T provisions provided accurate estimates of the axial capacities of GGBFS concrete CFST columns.Furthermore, embodied energy (EE) and cost of CFSTs with different concretes are also compared. EE and cost of CFST was reduced linearly with the increase in GGBFS content in concrete.

Learned Prediction of Compressive Strength of GGBFS Concrete Using Hybrid Artificial Neural Network Models.

A new hybrid intelligent model was developed for estimating the compressive strength (CS) of ground granulated blast furnace slag (GGBFS) concrete, and the synergistic benefits of the hybrid algorithm as compared with a single algorithm were verified. While using the collected 269 data from previous experimental studies, artificial neural network (ANN) models with three different learning algorithms namely back-propagation (BP), particle swarm optimization (PSO), and new hybrid PSO-BP algorithms, were constructed and the performance of the models was evaluated with regard to the prediction accuracy, efficiency, and stability through a threefold procedure. It was found that the PSO-BP neural network model was superior to the simple ANNs that were trained by a single algorithm and it is suitable for predicting the CS of GGBFS concrete.

Accelerating the reaction kinetics and improving the performance of Na2CO3-activated GGBS mixes

This study aimed to accelerate the reaction kinetics and improve the performance of Na2CO3-activated ground granulated blast-furnace slag (GGBS) via the use of reactive MgO and hydromagnesite seeds. The effect of 3–10% MgO and 0.5–1% seeds on the reaction mechanisms of Na2CO3-activated pastes was evaluated by pH, isothermal calorimetry and setting time measurements. Compressive strength results were used to assess the mechanical performance of the Na2CO3-activated GGBS concrete. A thorough investigation involving XRD, TG-DTG, and 29Si and 27Al solid-state NMR was performed to investigate the evolution of different phases. The inclusion of MgO and seeds promoted the removal of CO32−, increasing the pH and accelerating the dissolution of GGBS. The improved reaction kinetics via the use of MgO and seeds led to samples with shortened setting times, increased hydration and enhanced performance (43 vs. 14 MPa at 28 days) when compared to the control sample.

Physicochemical properties of alkali activated GGBS and fly ash geopolymeric recycled concrete

Reuse of recycled aggregates (RA), which are from construction and demolition wastes, and fly ash and ground granulated blast furnace slag (GGBS), which are from industry by-products, in geopolymeric recycled aggregate concrete (GRAC) could provide a sustainable solution to deal with the increasing construction waste and to reduce the CO2 emission from OPC production. This work aims to investigate the workability, mechanical performance and hydration mechanism of GGBS and fly ash based alkali activated GRAC. In this study, the RA were used to replace different levels (0%, 30%, 50%, 70% and 100%) of natural aggregates, and GGBS and fly ash based geopolymer was used to replace 100% of OPC. A series of slump, setting time, compression, XRD and SEM tests were conducted to evaluate the effects of RA content and water-binder ratio on the physicochemical properties of this green concrete. It is found that the combination of fly ash and GGBS based geopolymer and RA can provide an excellent compression resistance in concrete. The compressive failure of GRAC was dominated by the defects in RA and the ITZ. However, the denser geopolymer matrix could modify these shortages in RA and the ITZ, resulting in that GRAC have better mechanical properties than conventional concrete.

Durability and rheological characteristics of high-volume ground-granulated blast-furnace slag concrete containing CaCO3/anhydrate-based alkali activator

In this paper, durability and rheological characteristics of binary blended mixtures incorporating high-volume ground-granulated blast-furnace slag (GGBFS) were assessed based on a series of laboratory tests. Various durability characteristics such as restrained shrinkage cracking, freeze-thaw resistance, carbonation resistance, and chloride ion diffusion resistance were comprehensively investigated. The experimental results verified that the high-volume GGBFS replacements with a CaCO3/anhydrate-based alkali activator effectively improved the overall durability performance, especially when a replacement level of 70% was used. The promoted durability was mainly attributed to the formation of dense microstructure and low capillary porosity resulting from the enhanced degree of latent hydraulic and pozzolanic reactivity of GGBFS in the presence of alkali activator, which transformed a number of weak phases in cement hydrates (Ca(OH)2) into dense calcium silicate hydrate (CSH) phases. It was also found that the flow behavior was largely affected by the GGBFS replacement level, use of alkali activator, and elapsed time after mixing. Based on the findings of the present study, the high-volume GGBFS replacement, up to 70–80 wt%, appears to be a substantial strategy for enhancing the durability and sustainability of concrete.

The Nature-Inspired Metaheuristic Method for Predicting the Creep Strain of Green Concrete Containing Ground Granulated Blast Furnace Slag

The aim of this study was to develop a nature-inspired metaheuristic method to predict the creep strain of green concrete containing ground granulated blast furnace slag (GGBFS) using an artificial neural network (ANN)model. The firefly algorithm (FA) was used to optimize the weights in the ANN. For this purpose, the cement content, GGBFS content, water-to-binder ratio, fine aggregate content, coarse aggregate content, slump, the compaction factor of concrete and the age after loading were used as the input parameters, and in turn, the creep strain (εcr) of the GGBFS concrete was considered as the output parameters. To evaluate the accuracy of the FA-ANN model, it was compared with the well-known genetic algorithm (GA), imperialist competitive algorithm (ICA) and particle swarm optimization (PSO). Results indicated that the ANNs model, in which the weights were optimized by the FA, were more capable, flexible and precise than other optimization algorithms in predicting the εcr of GGBFS concrete.