V-funnel Tests Research Articles

Performance analysis of self compacting concrete by incorporating fly ash, coal gangue powder, cement kiln dust and recycled concrete powder by absolute volume method

To achieve environmental sustainability and improve material characteristics, this study examines the performance of self-compacting concrete (SCC) that incorporates different industrial by-products, including fly ash (FA), coal gangue powder (CGP), cement kiln dust (CKD), and recycled concrete powder (RCP). Through an experimental program, the research evaluates the fresh and hardened properties of SCC as well as its microstructural features. Slump flow, T50, and V-funnel tests were utilized to evaluate the fresh characteristics, while the compressive strength was the main emphasis of the hardened property at 7, 14, and 28 days of curing periods. To clarify the internal structure of the material and the pozzolanic processes taking place therein, further microstructural investigations were carried out using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Due to pozzolanic reactions and the densification of the microstructure, the results show that adding these industrial by-products not only makes SCC more workable but also gradually increases its compressive strength. In particular, the study shows that combinations with FA, CKD, and RCP perform better than CGP in terms of flowability and strength development. The results highlight the technical advantages of improving concrete qualities through material innovation, in addition to the possible environmental benefits of recycling waste materials in construction.

Rheological properties of high-performance SCC using recycled marble powder

Due to the impacts of cement manufacturing and depletion of the natural aggregates for concrete production, recycling of construction and demolition waste materials has become an alternative replacement to natural materials that lower their consumption and satisfy the environment. One of these alternatives is replacing cement with recycled materials from marble, ceramic, granite, and concrete wastes or even replacing the coarse aggregate with crushed marble and other stone wastes. Marble, granite, and natural stone wastes rapidly increase each year due to unmanaged waste disposal processes and the incremental increase in construction potential. Marble slurry, which comes from washing and cleaning marble surfaces, shows a filler effect by giving the concrete a denser and homogenous structure. This study evaluates the marble filler effects on the rheology in the fresh state of self-compacting concrete (SCC) through four SCC mixes by incorporating 10% marble powder (MP) and 33% fly ash (FA) as a partial ordinary Portland cement (OPC) replacement. Tests on paste and mortar were conducted to assess the suitability of the marble dosage on the water content and the superplasticizer amount. Spread flow and V-funnel tests were assessed. The results showed that mixes with MP required additional mixing water to ensure the same workability. Regardless of the high viscosity and air content, the overall developed marble SCC mixes reduced the cement quantity by up to 11% and provided excellent rheological properties like that of the reference mix. Besides the economic benefits, this transformation of waste to valuable materials involves environmental advantages and sustainability promotion.

Investigating Some Properties of Hybrid Fiber Reinforced LECA Lightweight Self-Compacting Concrete

. The primary goal of this investigation is to study the effect of using mono and hybrid fibers on the fresh and hardened characteristics of Lightweight Self-Compacting Concrete (LWSCC). Slump flow test, L-box test, sieve segregation test, and V-funnel test were used to evaluate the workability of LWSCC. The mechanical characteristics of LWSCC were assessed by using compressive strength, splitting strength, and flexural strength. Four mixtures using two types of fiber: Steel fiber (St) and polypropylene fiber (PP) (0% fiber, 1% (St), 0.75% (St) +0.25% (PP), 0.5% (St) +0.5% (PP)) were made. According to the results, (St) fiber and hybrid fiber addition to LWSCC reduced its workability, although the values of tests were still within the acceptable range stander of EFNARC. The findings indicated a decrease in the values of slump flow and L-box test by adding mono and hybrid fibers to the LWSCC mixture. While the T500mm and V_ funnel tests increased by adding mono and hybrid fibers to LWSCC mixture. The results also indicate that the utilisation of (St) fiber and hybrid fibers had a significant effect on the mechanical characteristics of LWSCC. Where the flexural and splitting strengths significantly increase with the addition of (St) and hybrid fibers to the LWSCC mix.

Optimization of recycled rubber self-compacting concrete: Experimental findings and machine learning-based evaluation

This research aims to assess the rheological and mechanical characteristics of Self-compacting concrete (SCC) incorporating waste tire rubber aggregates (WRTA) as an interim substitute for coarse aggregates. However, the standard experimental modeling approach has significant obstacles when it comes to overcoming the nonlinearity and environmental susceptibility of concrete parts. Therefore, linear regression (LR) and extreme gradient boosting (XGBoost) were used as two standard single machine learning (ML) models to predict the aforementioned rubberized SCC features. In this study, conventional coarse aggregates were supplanted with WRTA at 0%, 5%, 10%, and 20% to uncover the optimal proportion of coarse aggregates substituting rubber. To find the optimum amount of WRTA to use as a substitute, the study follows the impacts of rubber on the self-compacting rubberized concrete's (SCRC) rheological and mechanical characteristics. The consequences on fresh properties were investigated by the slump flow, J-ring, and V-funnel tests, while compressive and splitting tensile strengths tests were conducted to assess mechanical properties. Increasing WRTA test outputs indicated a deterioration in workability and hardened qualities. While a 10% swapping ratio is deemed feasible for producing SCRC, optimal results were achieved by reducing environmental impacts and efficiently managing a significant volume of rubber tire waste with a 5% substitution of rubber within the coarse aggregates. The research findings indicated a noticeable decrease in fresh properties as the WRTA content increased. Notably, after 28 days, a 10% WRTA substitution led to a 34% reduction in compressive strength and a 28% decrease in splitting tensile strength, satisfying ACI standards. Furthermore, XGBoost demonstrated superior predictive performance with the highest R2 values, outperforming the LR model and affirming its efficacy in delivering more accurate predictions.

The effect of JKR surface energy on the flowing property of fresh concrete in DEM simulation

The effect of Johnson–Kendall–Roberts (JKR) surface energy on the flowing property of fresh concrete was numerically studied. The fresh concrete was simplified into coarse aggregate and mortar, both described as the particles. The Hertz-Mindlin with JKR contact model was employed to describe the constitutive relationship of fresh concrete. The contact parameters were calibrated through experiment and numerical simulation of multiple flow tests. The impact of these contact parameters on the residual height (Hr) of fresh concrete after slumping was examined using a slump test. The significance degree of mortar–mortar contact parameters on the Hr was studied using an orthogonal test. The effect of the surface energy ( γ ) on the flow index (Bm) and flow time (Tv) of fresh concrete was studied intensively based on the L-box flow and V-funnel tests. The mortar–mortar contact parameters, γ and rolling friction coefficient (μ r), most significantly impacted the Hr. The mortar–mortar surface energy ( γ m-m) significantly impacted Bm and Tv compared to the aggregate–mortar and aggregate–aggregate surface energies (( γ a-m) and ( γ a-a), respectively). The effect of γ a-a, γ a-m, and γ m-m on Bm was interconnected. Under appropriate parametric values, the Bm was the most stable, and the workability of fresh concrete was the best. In addition, as γ increased, Hr and Bm decreased and Tv increased. The flowability of the fresh concrete worsened.

Properties of ultra-high-performance self-compacting fiber-reinforced concrete modified with nanomaterials

Abstract Utilizing waste materials to produce sustainable concrete has substantial environmental implications. Furthermore, understanding the exceptional durability performance of ultra-high-performance concrete can minimize environmental impacts and retrofitting costs associated with structures. This study presents a systematic experimental investigation of eco-friendly ultra-high-performance self-compacting basalt fiber (BF)-reinforced concrete by incorporating waste nanomaterials, namely nano-wheat straw ash (NWSA), nano-sesame stalk ash (NSSA), and nano-cotton stalk ash (NCSA), as partial substitutes for Portland cement. The research evaluates the effects of varying dosages of nanomaterials (ranging from 5 to 15% as cement replacements) in the presence of BFs. Rheological properties were analyzed, including flow diameter, L-box, and V-funnel tests. Additionally, the study investigated compressive, splitting tensile, and flexural strengths, load-displacement behavior, ultrasonic pulse velocity, and durability performance of the ultra-high-performance self-compacting basalt fiber (BF)-reinforced concrete (UHPSCFRC) samples subjected to sulfate attack, freeze-thaw cycles, autogenous shrinkage, and exposure to temperatures of 150, 300, 450, and 600°C. Microstructural characteristics of the mixtures were examined using X-ray diffraction (XRD) analysis. The findings reveal that self-compacting properties can be achieved in the UHPSCFRC by incorporating NWSA, NSSA, and NCSA. The presence of 10% NWSA significantly improved the mechanical properties of the UHPSCFRC, exhibiting more than 27.55% increase in compressive strength, 17.36% increase in splitting tensile strength, and 21.5% increase in flexural strength compared to the control sample. The UHPSCFRC sample with 10% NWSA demonstrated superior performance across all extreme durability tests, surpassing both the control and other modified samples. XRD analysis revealed the development of microcracking at temperatures of 450 and 600°C due to the evaporation of absorbed and capillary water and the decomposition of ettringites.

Effect of recycled crushed glass and recycled coarse aggregate on the properties of self-compacting concrete

This research was developed to use recycled coarse aggregate (RCA) and recycled crushed glass (RCG) to produce self-compacting concrete (SCC) mixtures. Natural coarse aggregate (NCA) was replaced by RCA from 0% to 100%, and natural fine aggregate (NFA) was replaced by RCG from 0% to 20%. Slump flow with T500 time, L-box, and V-funnel tests were done to ascertain the workability properties of SCC mixtures. The mechanical properties studied were compressive, flexural, and splitting tensile strength at 28 and 56 days. Ultrasonic pulse velocities (UPV) were also measured for the SCC mixtures at 28 and 56 days. Ten shear-critical beams with different shear span-to-depth (a/d) ratios were also cast and tested under 4-point bending. Cracking load, failure load, load-midspan deflection curves, and deflection corresponding to ultimate load were observed. The recommendations of the American Concrete Institute (ACI 318–14 and ACI 318–19), Eurocode (EC2), and Japanese Society of Civil Engineers (JSCE) for shear design were also evaluated on a database of 222 beams cast with SCC and recycled aggregate concrete (RAC) along with the beams tested in the presented study. Results indicate that the workability and mechanical properties were reduced when the replacement level of RCA was increased. The use of RCG as a replacement for NFA enhanced the workability properties and mechanical properties at the age of 56 days. The replacement of NCA with RCA slightly reduced the shear capacity and stiffness of the RC beams. However, the shear capacity and stiffness of RC beams improved when NFA was replaced with RCG. The design provisions of ACI 318–19 yielded accurate estimates of shear capacity compared to JCSE, EC 2, and ACI 318–14.

Mechanical and shrinkage performance of steel fiber reinforced high strength self-compacting lightweight concrete

This study investigated the effects of mixture proportion on the mechanical and shrinkage behaviors of steel fiber reinforced high strength self-compacting lightweight concrete (SHSLC) mixtures incorporating bottom ash aggregates for internal curing. In this study, different types of fine aggregates, fine aggregate ratios, supplementary materials such as silica fume (SF) and colloidal nano-silica (CNS), and four types of steel fibers were considered to develop SHSLC. The self-compacting characteristics of concrete were evaluated by means of slump flow, J-ring flow, and V-funnel tests. The test results indicate that incorporation of SF and CNS had a positive effect on the mechanical properties, but 4% incorporation of CNS decreased workability and strength due to the agglomeration of mixture. The addition of steel fibers improved compressive strength, and flexural toughness of SHSLC, but reduced the flowability and passing ability with increased fiber contents. Due to the internal curing from coarse bottom ash, significant reduction of autogenous shrinkage up to 33% was observed, whereas 7% for drying shrinkage. The incorporation of fibers reduced the autogenous and drying shrinkage up to 31% and 22% compared with non-fiber reinforced concrete, respectively. Finally, the autogenous shrinkage behavior was simulated with several models in the literature, and a model for high strength self-compacting lightweight concrete with and without fibers considering equivalent age was proposed.

Machine Learning Models for the Prediction of the Compressive Strength of Self-Compacting Concrete Incorporating Incinerated Bio-Medical Waste Ash

Self-compacting concrete (SCC) is a special form of high-performance concrete that is highly efficient in its filling, flowing, and passing abilities. In this study, an attempt has been made to model the compressive strength (CS) of SCC mixes using machine-learning approaches. The SCC mixes were designed considering lightweight expandable clay aggregate (LECA) as a partial replacement for coarse aggregate; ground granulated blast-furnace slag (GGBS) as a partial replacement for binding material (cement); and incinerated bio-medical waste ash (IBMWA) as a partial replacement for fine aggregate. LECA, GGBS, and IBMWA were replaced with coarse aggregate, cement, and fine aggregate, respectively at different substitution levels of 10%, 20%, and 30%. M30-grade SCC mixes were designed for two different water/binder ratios—0.40 and 0.45—and the CS of the SCC mixes was experimentally determined along with the fresh state properties assessed by slump-flow, L-box, J-ring, and V-funnel tests. The CS of the SCC mixes obtained from the experimental analysis was considered for machine learning (ML)-based modeling using paradigms such as artificial neural networks (ANN), gradient tree boosting (GTB), and CatBoost Regressor (CBR). The ML models were developed considering the compressive strength of SCC as the target parameter. The quantities of materials (in terms of %), water-to-binder ratio, and density of the SCC specimens were used as input variables to simulate the ML models. The results from the experimental analysis show that the optimum replacement percentages for cement, coarse, and fine aggregates were 30%, 10%, and 20%, respectively. The ML models were successful in modeling the compressive strength of SCC mixes with higher accuracy and the least errors. The CBR model performed relatively better than the other two ML models, with relatively higher efficiency (KGE = 0.9671) and the least error (mean absolute error = 0.52 MPa) during the testing phase.

Properties of Self-Compacting Concrete Produced with Optimized Volumes of Calcined Clay and Rice Husk Ash-Emphasis on Rheology, Flowability Retention and Durability.

The durability of concrete requires a dense microstructure which can be achieved by using self-compacting concrete (SCC). Both calcined clay (CC) and rice husk ash (RHA) are promising supplementary cementitious materials (SCMs) that can partially replace cement, but their use in SCC is critical due to their higher water demand (WD) and specific surface area (SSA) compared to cement. The effect of partial substitution of cement at 20 vol-% with binary and ternary blends of CC and RHA on flowability retention and durability of SCC was investigated. The empirical method of SCC design was adopted considering the physical properties of both CC and RHA. The deformability of the SCC was evaluated using the slump flow and J-ring tests. The T500 time and the V-funnel test were used to assess the viscosity of the SCC. The flowability retention was monitored by the plunger method, and flow resistance was determined based on the rheological measurements of SCC. The evolution of the hydrate phases of the binder in SCC was determined by thermogravimetric analysis, while the durability was evaluated by a rapid chloride migration test. Cement partial replacement with 20 vol-% CC has no significant effect on fresh SCC, flowability retention, compressive strength and durability properties. On the other hand, 20 vol-% RHA requires a higher dosage of SP to achieve self-compactability and increase the viscosity of SCC. Its flowability retention is only up to 30 min after mixing and exhibited higher flow resistance. It consumes more calcium hydroxide (CH) and improves the compressive strength and chloride resistance of SCC. The ternary blending with CC and RHA yielded better fresh SCC properties compared to the binary blend with RHA, while an improved chloride penetration resistance could be achieved compared to the binary CC blend.

Effect of Local Feldspar on the Properties of Self Compacting Concrete

This research of using Feldspar in the production self compacting concrete (SCC) ( 5,10,15 )% as partial replacement by weight of cement .In this research some of fresh properties of SCC ( slump flow used V-funnel test and filling ability used ( U- box test ) for concrete mixes and also some of the harden properties of SCC ( compressive and flexural tests ). The research results showed that negative effect of Feldspar on the fresh properties of self compacting concrete but the positive effect of Feldspar on the harden properties of self compacting concrete .

Impact and durability properties of alccofine-based hybrid fibre-reinforced self-compacting concrete

Many research works have already been made and are still in progress on metallic fibres, as their incorporation reduces the brittleness of the concrete and improves its resistance to the impact and crack propagation. But the use of such non-metallic fibres may induce corrosion which is a major problem to be addressed from the durability aspect. To overcome this problem, in the present research work, a non-metallic hybrid fibre combination was investigated with synthetic fibres like polypropylene and abaca fibres. Also, rather than using conventional cementitious materials such as silica fume, fly ash, and ground granulated blast furnace slag, a new generation of ultra-fine material namely alccofine was used as a partial replacement for the cement by 15%. Abaca fibre was utilised in a constant addition of 0.5% and blended with polypropylene fibre in a range varying from 0% to 2% with an increment of 0.5%. The fresh properties of self-compacting concrete (SCC) in mono and hybrid fibres combinations were assessed through slump flow, J-ring, and V-funnel tests. Water absorption and sorptivity tests were conducted to ensure the durability of the prepared mix. Further, impact tests were carried out on the prepared cylinder specimens to check the capability of the mix with the non-metallic hybrid combination. The main objective here was to check whether a high-strength durable SCC could be achieved using non-metallic fibres and natural fibres. From the obtained experimental results, it was observed that 15% alccofine as a partial substitute to the cement with the addition of 0.5% of abaca fibre and 2% of polypropylene fibre to SCC performed better than the control SCC.

Pull-Out behavior and microstructure characteristics of binary blended self-compacting geopolymer concrete subjected to elevated temperature

Geopolymer concrete (GPC) is an emerging green substitute for conventional cement-based concrete. Due to the eco-friendly benefits of GPC, it possesses superior strength properties. Self-compacting concrete (SCC) is a special concrete, it has the tendency to pass and fill congested areas without the help of vibrators. As the Self-compacting based Geopolymer concrete (SCGC) is a sustainable construction material, the knowledge about the thermal performance of SCGC is vital. Therefore, the current work examined the behavior of binary blended SCGC under room temperature and elevated temperatures of 821 °C, 925 °C, 986 °C, and 1029 °C. The investigation's main objectives are to examine the bond performance and microstructure of binary blended SCGC composites subjected to temperature exposure. Three types of mixes are considered in the investigation, namely FA (100% Fly Ash (FA)), F-G (50% Fly Ash (FA) and 50% Ground Granulated Blast Furnace Slag (GGBS)), and F-M (50% Fly Ash (FA) and 50% Metakaolin (MK)). The workability tests, such as the Flow test, T500 test, V-funnel test, and J-ring tests, were carried out in line with EFNARC guidelines to examine the rheological properties of SCGC. The SCGC composites were subjected to temperature exposure following ISO 834 standard fire curve. The Pull-Out (PO) test was carried out to investigate the Bond stress (BS) of the heated and unheated SCGC composites. The Bond stress of the SCGC composites decreases with an increase in temperature exposure. Test results show that the F-G mix possesses higher BS for unheated specimens, followed by F-M and FA mix. When exposed to elevated temperature, the SCGC composite mix F-G and F-M exhibit higher strength loss (%) than the FA mix. A relationship has been established between the compressive and bond stress of SCGC.

An experimental investigation of M30 grade self compacting concrete using mineral admixtures

Self-compacting concrete (SCC) is commonly used to create high-performance concrete since it does not require vibration to achieve a compacted state. The absence of standardized mix design and testing methods has hampered SCC's implementation. Since no vibration is required and noise pollution is reduced, it is gaining widespread acceptance. In construction, we have found a way to make every step of the process both less dangerous and more fruitful. This study aimed to produce a mix design for M30 grade SCC by the criteria established by EFNARC 2002. The SCC is made by substituting fly ash (FA) and metakaolin (MK) at percentages of 0%, 7.5%, 15%, 22.5%, and 30% of the cement volume and then adding 1.5 percent of superplasticizer to the resulting cement volume. According to EFNARC, the M30 grade SCC mix produced passed all of the tests above: the L-box test, the slump flow test, the V-funnel test, and the J-ring test. Additionally, compressive, tensile, and flexural strengths of 7- and 28-day-old SCC samples were tested, with results indicating that a 0%-30% substitute of MK and FA can be considered a suitable replacement and mix designs for M30 grade of metakaolin and fly ash-based self-compacting concrete have been proposed.

Recycling prestressed concrete pile waste to produce green self-compacting concrete

Construction and demolition waste is produced in large quantities and constitutes an overlooked resource with significant potential for recycling and reuse. In fact, recycled concrete aggregate (RCA) has a high resource value, although it is also the case that RCA has characteristics that complicate its reuse. This research study looks at the efficacy of producing green self-compacting concrete (SCC) using uniform in-situ prestressed concrete pile waste (RCA) as a replacement for natural aggregate and fly ash (FA) as a replacement for Type 1 Portland cement (OPC). In accordance with the European standard, the workability characteristics of the SCC mixtures were assessed using slump flow, T500 time, J-ring flow, L-box, and V-funnel tests. The hardened properties of compressive strength at 7, 28, and 91 days as well as pulse velocity, Young's modulus, and surface resistivity were also tested. Based on this study, it is possible to produce SCC with both RCA and FA that has better workability and hardened properties than does RCA and also to reduce the negative effects of the latter. SCC produced without coarse natural aggregates showed compressive strength above 50 MPa and maximum compressive strength above 74 MPa at 91 days. SCC produced in this way is, therefore, viable for industrial use.

Experimental study on the strength parameters of self compacting concrete reinforced with carbon fibre

Concrete being the most used material in construction, resulting to an increase in carbon footprint at a global rate. This results to the increasing search of sustainable concrete as a construction materials and Self compacting concrete (SCC) is one such example. Self-Compacting Concrete (SCC) is a special type of concrete that does not require any kind of compaction or vibration wherein flows under its own weight. This type of concrete can flow easily around the reinforced areas and into all over the formwork economically reducing the time for other works, labour and energy. Many studies had been carried so as to know the effectiveness of carbon fibres (CF’s) on the various properties of concrete. Addition of carbon fibres to concrete may offer significant improvements to the concrete’s fresh and hardened properties such as filing ability, passing ability, compressive strength, flexural strength etc. CFs are being attractive due to their thermal conductivity and low density. In this paper, the fresh and hardened properties of SCC were carried out by the following tests like V-Funnel test, Slump flow test etc. for the fresh properties and test for compressive strength and flexural tests were carried out. Chopped carbon fibres were added to the SCC in different percentages of 0.1%, 0.15% and 0.20% respectively and studied the optimum percentage of addition in acquiring the results. Optimum percentage for addition of CF to SCC was found at 0.15%.

3D printable concrete: Mixture design and laboratory test methods

Experimental results of the mix design and fresh properties of a proposed concrete for 3D printing are presented in this paper. Layer-by-layer sample components were built by the designed concrete and extruded through a nozzle. The two most critical rheological properties of the designed mix are extrudability and buildability as they are both highly influenced by mix proportion and the presence of superplasticizers. Therefore, this study focused on mix proportion design approaches and laboratory test methods, which generally allowed access to the fresh concrete’s printable properties. Because they are efficient and convenient in construction, materials including cement, fly ash, natural sand, and superplasticizer were selected for mixing proportion analysis. Slump-flow tests, V-funnel tests, buildability tests, and extrudability tests were also employed to access the printability of the proposed mixture in this study. This first analysis on the mixture design approach and laboratory test methods to evaluate the printable properties of 3D-printable concrete can be considered a reference and orientation to further develop 3D printing technology in Vietnam.

Comparing and evaluating influence of nylon fiber and fly ash in self compacting concrete

Self-consolidating concrete (SCC) is a special concrete that is highly flow able, non-segregating and self-expanding. Self-compacted concrete (SCC) is poured into the formwork without compaction and fills the formwork by its own weight. SCC is considered to have many advantages. Compared with conventional concrete as improved Construction quality, faster construction activity, lower cost etc. This project was carried out to evaluate the effects of addition of nylon fiber and fly ash on the fresh and hardened properties of SCC mixes. In this project, concrete mixes with nylon fiber of 0.5%, 1.5%, 2.5%, and fly ash with 0%, 15%, 30% and 45% were used to determine its permeability, flow Capacity, evaluated on the basis of and separation resistance, slump flow, L-box and V-funnel tests. After 3 days, 14 days, 28 days of curing SCC cylinders, compressive and splitting tensile strength were tested. The test results show that nylon fibers increase permeability but decrease the filling capacity and segregation resistance of SCC. Furthermore, it can be concluded that after 3 days, 14 days, 28 days of curing, the test of concrete samples showed that the addition of nylon fiber up to 2.0% of cement by volume increased the compressive strength of SCC. Strength, improves tensile strength but 2.5%. Nylon fiber reduces the compressive strength, tensile strength of hardened SCC.

Evaluation of the Rheological and Durability Performance of Sustainable Self-Compacting Concrete

Self-Compacting Concrete (SCC) is a special concrete that can flow easily across congested reinforcements. Also, it is easy to work with and does not segregate. The present investigation aims at the design and development of sustainable SCC with the employment of industrial by-products such as Fly Ash (FA), Ground Granulated Blast Furnace Slag (GGBFS), and Expanded Perlite Aggregate (EPA). Four SCC mixes were developed to attain a target strength of 30 MPa. Workability tests (slump flow, J-ring, and V-funnel tests) were performed following the EFNARC guidelines to ensure fresh SCC properties. Detailed experiments were conducted to evaluate the durability characteristics of the developed SCC, such as water absorption, sorptivity, acid attacks (sulphuric, nitric, sulphate, and chloride), the Rapid Chloride Penetration Test (RCPT), and finally, the elevated temperature test. Weight loss, strength loss, and physical observations of the acid and temperature effects of SCC mixes were evaluated. Also, the study focuses on the cost and sustainable index of SCC mixes and compares them with OPC mixes. From the experimental data analysis, it was observed that the developed SCC showed excellent physical and mechanical properties with a considerable reduction in cement content. SCC specimens with FA and EPA exhibit excellent acid and temperature resistance. Following the sustainable analysis, it was noted that SCC mixes reduce about 15–17.2% of carbon emissions compared to the OPC mix.

New hybrid support vector regression methods for predicting fresh and hardened properties of self-compacting concrete

Most of the published literature on concrete containing fly ash was limited to predicting the hardened properties of concrete. It is understood that exist so restricted studies focusing on forecasting both hardened and fresh features of self-compacting concrete (SCC). Hence, it is goaled for developing models for predicting the fresh and hardened properties of SCC by the support vector regression method (SVR). This study aims to specify SVR method key parameters using Ant lion optimization (ALO) and Biogeography-based optimization (BBO) algorithms. The considered properties of SCC in the fresh phase are the L-box test, V-funnel test, slump flow, and in the hardened phase is CS. Results demonstrate powerful potential in the learning section for all considered properties as well as approximating in the testing phase. It can be seen that the proposed models have R2 incredible value in the learning and testing phase. It means that the correlation between observed and predicted properties of SCC from hybrid models is acceptable so that it represents high accuracy in the training and approximating process. All in all, in most of the cases, the SVR model developed by ALO outperforms BBO-SVR, which depicts the capability of the ALO algorithm for determining the optimal parameters of the considered method.