Volume Of Concrete Research Articles

Parametric study of molten core concrete interaction and assessment of corium coolability in the light of MCCI experiments

Molten Corium Concrete Interaction (MCCI) is an important phenomenon observed in the late phase of reactor severe accidents. A realistic analysis of MCCI can save cost and efforts to mitigate severe accidents. The heat transfer mechanisms in MCCI, such as melt eruption and water ingression, are the primary focus of current research owing to complications in their quantification and replication in severe accident analysis codes. This study investigated MCCI using top flooding strategy with MELCOR 2.2 code for two concrete types, and three experiments that were conducted under (OECD/MCCI-1 program). The results demonstrated that the ablation process terminated in the case of Limestone Common Sand (LCS) concrete. In the simulation of siliceous (SIL) concrete, the maximum and average melt front locations confirmed the asymmetrical ablation progression. The LCS concrete showed a smaller axial ablation front in this study; however, the comparison with the concrete ablation volume (0.21 m3) showed an exact match, and the difference between the experimental and predicted ablated mass of concrete was only 0.61%. The quantitative comparison between the prediction of the present study, CORQUENCH code, and experimental results is provided. The parametric values of MCCI phenomenon are also predicated and model improvement for MELCOR 2.2 code are discussed as well.

Tests and finite element modeling of concrete beams reinforced with reused steel bars

AbstractThis paper presents the experimental study and finite element modeling of the flexural behavior of concrete beams reinforced with reused steel bars as longitudinal reinforcements. The experimental program and results of eight reinforced concrete (RC) beams constructed with and without reused steel bars are described in detail. The replacement percentages of brand‐new bars with reused steel bars in the tested beams were 50% and 100%. The reused steel bars were coated with and without epoxy. Steel fibers with fractions of 0.5% and 1.0% of the concrete volume were added to the concrete mixes. The load‐deflection relationship, ductility index, toughness, and failure modes of the tested beams are presented and discussed. It is shown that utilizing reused steel bars decreases the ultimate load of RC beams but increases their deflection at the ultimate load compared with the control beam. Increasing the steel fiber ratio increases the ultimate load and the deflection at the ultimate load of RC beams incorporating reused steel bars. However, the zinc‐rich epoxy used to coat the reused steel bars does not affect the behavior of the beams. Three‐dimensional nonlinear finite element (FE) models of the tested beams were developed using ABAQUS and validated against the test results. The developed FE models are capable of accurately simulating the experimentally observed behavior of RC beams with reused steel bars.

Sleeved waveguide ultrasonic sensor for monitoring concrete health

This article reports the development of a novel embedded waveguide ultrasonic sensor for detecting the onset of damage in reinforced concrete structures. A sleeved waveguide is proposed to confine guided ultrasonic waves in one-dimension, with leakage to the surrounding media only through specially created openings, thus reducing attenuation losses and enhancing the capability to inspect large structures from a single transducer location. The test frequency and mode are identified through modelling, and the interaction of leaky guided ultrasonic waves with delamination within the concrete volume is studied. Numerical simulations validated by experiments are used to study the changes in wave features such as mode velocity, wavelength and wave reflection in the delamination region, helping to estimate its location. Further simulation studies are carried out to demonstrate the possibility of using multiple waveguide sensors and sleeve openings to provide a full view of the concrete volume. The results are encouraging for practical long-range and large-scale monitoring of concrete volumes using the proposed sleeved waveguide ultrasonic sensors.

The Effect of Using Different Aspect Ratios of Sustainable Copper Fiber on Some Mechanical Properties of High-Strength Green Concrete

To achieve sustainability, use waste materials to make concrete to use alternative components and reduce the production of Portland cement. Lime cement was used instead of Portland cement, and 15% of the cement's weight was replaced with silica fume. Also used were eco-friendly fibers (copper fiber) made from recycled electrical. This work examines the impact of utilizing sustainable copper fiber with different aspect ratios (l/d) on some mechanical properties of high-strength green concrete. A high-strength cement mixture with a compressive strength of 65 MPa in line with ACI 211.4R was required to complete the assignment. Copper fibers of 1% by volume of concrete were employed in mixes with four different aspect ratios (20, 40, 60, and 120). At 7, 28, and 60 days after typical curing, the samples' mechanical characteristics (compressive strength, flexural strength, and split tensile strength) are assessed. A reported increase in compressive strength of (2, 1.6, and 1.4) in (7, 28, and 60 days) for concrete with a high aspect ratio 120, compared to concrete with a low aspect ratio 20. The flexural strength of high-strength green concrete with fibers of a higher aspect ratio 120 was (23, 11, and 12.6%) times higher for all ages compared to low aspect ratio 20. The split tensile strength rose (1.7, 1.5, and 1.6%) for (7, 28, and 60 days), respectively, for concrete with a high aspect ratio 120, compared to concrete with a low aspect ratio 20. It was found that using fibers with a large aspect ratio improved the mechanical properties of concrete more than fibers with a small aspect ratio.

Research on some properties of lightweight concrete using recycled expanded polystyrene aggregates

This paper presents an experimental study to determine the effects of recycled expanded polystyrene aggregates (REPS) on workability, compressive strength, flexural tensile strength, and concrete density. REPS was used with four levels of content: 30%, 40%, 50%, and 60% by volume of concrete. The result shows that when increasing the REPS content, the workability of the concrete mix decreases, especially when the REPS content used is up to 50-60%. The density of recycled expanded polystyrene concrete (REPSC) can be adjusted to 800-1000 kg/m3 when the REPS content is up to 50%-60%. The compressive and flexural tensile strengths of the REPSC tended to decrease sharply with increasing REPS content. In addition, the influence of the REPS on the flexural tensile strength was lower than that on the compressive strength. The strength of the REPSC can be adjusted by changing the strength of the binder phase through factors such as the W/C ratio and binder content.

Increased Concrete Strength with the Addition of Hyacinth Natural Fibers

Concrete is a brittle and fragile construction material so it needs to be increased in strength. This study aims to increase the strength of concrete by adding natural fibers of water hyacinth to the concrete mixture. Hyacinth fibers are cut by 3-5 cm and added with variations of 0%, 0.1%, 0.2%, 0.3%, 0.4% and 0.5% of the volume of concrete. Cylindrical specimens 15 cm in diameter and 30 cm in height were tested for compressive strength and tensile strength at the age of 28 days. The test results showed that the addition of hyacinth fiber up to 0.5% increased the compressive strength of concrete up to 17.6% and tensile strength up to 71.4% compared to normal concrete without fiber. The increase in strength is due to hyacinth fibers being able to withstand micro-cracks in concrete. The more fiber added, the more microcracks are able to be prevented thereby increasing the strength of concrete. In conclusion, the natural fiber of hyacinth effectively increases the strength of concrete both in compressive and tensile capacity.

Modeling and Optimizing Wastewater Stabilization Ponds for Domestic Wastewater Treatment

In Wastewater Stabilization Ponds (WSPs), baffle walls (BWs) have the dual benefit of reducing area requirements and increasing contaminant removal efficiency up to a certain threshold. However, this advantage is mitigated by the increased demand for construction materials, highlighting the need for optimization. Effectively optimizing WSPs to suit diverse climatic regions can substantially alleviate nationwide wastewater treatment challenges. This study focuses on optimizing WSPs across seven distinct climatic regions in Turkey. In the initial phase, a comprehensive analysis was conducted using design spreadsheets for the WSPs to determine the best configuration based on traditional methodology (TM). The results demonstrated a significant decrease in WSPs area and hydraulic retention time (RT), validating the effectiveness of BWs provision. However, this approach requires additional time and effort. Subsequently, mathematical modeling (MM) was used to further reduce the time required for the optimization process. Using the interior-point algorithm in MATLAB and the generalized reduced gradient (GRG) algorithm in MS Excel Solver, both algorithms within MM effectively decreased the WSPs area and RTby approximately 10%, while decreasing the required concrete volume by approximately 5% compared with TM. As other algorithms may yield better optimization, they can be investigated by developing specialized software for WSPs. Doi: 10.28991/CEJ-2023-09-11-014 Full Text: PDF

Perbandingan Analisis Struktur Gedung Laboratorium PGSD Universitas Samudra Metode Sistem Rangka Pemikul Momen Khusus Menggunakan ETABS dan BIM Tekla Struktural Designer

Indonesia is located on the fault line of the Eurasian and Indo-Australian plates which makes Indonesia prone to earthquakes. The structural design of the Special Moment Resisting Frame System (SRPMK) is required for reinforced concrete buildings in high earthquake-prone areas, it is hoped that using the SRPMK construction method can have a flexible structure. The purpose of this research is to discuss the comparison of test control of the Samudra University PGSD Laboratory Building with the Etabs application and the Tekla Structural Designer Application. The building structure under review is a reinforced concrete structure with 3 floors with a building length of 54 m, width of 18 m, and height of 16.8 m. The type of soil for the construction site is soft soil with earthquake design category D. Construction planning refers to SNI 1726 – 2019. The additional dead loads of floors and roofs are 0.672 and 0.710, the largest live loads are 7.18 kN/m², the earthquake loads with Ss and S1 are 0.68 and 0.34, the priority factor earthquake of 1.5 and a period of 20 seconds, the suction and compressive wind loads are -0.25 kN/m² and -0.41 kN /m². The results of structural analysis using the ETABS application and the Tekla Structural Designer application, the control values of the mass participation test, the fundamental natural vibration time, the base reaction, and the standard deviation between floors have met the requirements for earthquake-resistant building planning. The volume of concrete is 594.9 m³, the bone requirement for D22 is 3432.96 kg, D19 is 3605 4.89 kg, D16 is 26434.5 kg, D13 is 1774.72 kg, Ø12 is 6237.53 kg, Ø10 is 31599, 07 kg, Ø8 is 4589.31 kg

Experimental and Computational Research on the Shear Performance of Partially Filled Narrow-Width Steel Box-UHPC-Combined Girders under Negative Moment Action

To examine the vertical shear behavior of narrow-width steel box-UHPC (Ultra-High Performance Concrete) composite beams with partial filling under negative bending moments, a total of six test beams were created and constructed in this study. The variables considered during the design and fabrication process included the flange thickness of UHPC, the amount of steel fibers in UHPC, and the height of the concrete filling. Reverse static concentration loading was applied to the beams. Compared to the C40 concrete flange, the cracking load of the 1/2 plate thickness UHPC flange and pure UHPC flange increased by 55.6% and 66.7%, respectively. The yield load witnessed a rise of 17.3% and 22.7%, while the ultimate load experienced an increase of 7% and 13.1%. This suggests that incorporating steel fibers can regulate the formation of cracks, enhance the flexibility of the flanges, and improve the overall shear capacity of the composite beams. When steel fibers were used in the amount of 2% of the concrete volume, the cracking resistance of the flange plate was increased by 16.7%. Partially filled and fully filled composite beams exhibited a 7.7% and 30.8% augmentation in cracking load, a 35.3% and 49.9% increase in yield load, and a 41% and 83.2% elevation in ultimate load when contrasted with composite beams devoid of concrete infusion within the steel box. The above observation implies that the incorporation of concrete within the steel box significantly improves the yield strength and ultimate shear capacity of the composite beams. The shear strength of the narrow-width steel box-UHPC composite beams, which are partially filled, shows a significant relationship with the experimental results when applying the principle of component superposition.

Evaluation on Early Strength Development of Concrete Mixed with Non-Sintered Hwangto Using Ultrasonic Pulse Velocity.

Currently, in order to reduce the greenhouse gases of global warming, research on alternative cement materials is being actively conducted in the construction industry to reduce cement use, and it is judged to be important to evaluate the timing of form removal for the initial age. Therefore, in this study, we evaluated the initial mechanical properties of concrete in which cement was partially replaced with non-sintered hwangto (NHT). Specimens without NHT (namely, normal mortar (NM) and normal concrete (NC)) and specimens with NHT (namely, non-sintered hwangto mortar (HTM) and non-sintered hwangto concrete (HTC)) were prepared. NHT was substituted for 15% and 30% of cement. Two water-to-binder (W/B) ratios, 41% and 33%, were used to analyze the variation in the mechanical properties according to the cement and NHT content per unit volume of concrete. The compressive strength and ultrasonic pulse velocity (UPV) were measured. Experimental results indicated that compressive strength decreased with an increase in NHT content. The mortar with NHT substitution rates of 15% and 30% exhibited higher UPV than NM at a W/B ratio of 41%, in contrast to the behavior observed for concrete. The UPVs of most specimens were similar regardless of the NHT substitution rate. The correlation between the compressive strength and UPV of HTC was analyzed, and therefrom, exponential equations with a high correlation coefficient (R2) were proposed for strength prediction; the resulting predictions were compared with the results of previous compressive strength prediction models.

Load-Bearing Capacity of Reinforced Concrete and Fiber Concrete Cross-Beam Systems

The results of experimental studies and computer modeling of reinforced concrete and fiber concrete cross-beam systems are presented. The authors have made a special stand, the design of which allows to carry out researches of bearing capacity and deformability of such systems under the concentrated and distributed static loads. Samples made of reinforced concrete and steel fiber concrete and consisting of four mutually perpendicular beams of rectangular cross-section were tested. The specimens were reinforced in the lower zone with longitudinal reinforcement of 8 mm in diameter, two rods in each beam. Steel-fiber concrete specimens have an additional dispersed reinforcement of steel fiber with bent ends in an amount of 1% by volume of concrete. A procedure of finite-element modeling and calculation of cross-beam systems in the licensed program ANSYS 17.1 was developed, and a comparison of the results obtained experimentally and on the basis of computer modeling was performed. The tests showed that dispersed reinforcement of the cross-beam system with steel fiber leads to an increase in its bearing capacity by 1.23 times. During modeling and finite-element analysis in the ANSYS 17.1 program, the increase in bearing capacity was 1.18 times. At the same time, the load-carrying capacity of the reinforced concrete cross-beam system obtained by the finite-element method was 13% lower than in the experiment, and that of the fiber-reinforced concrete system was 15% lower. At the same time, the discrepancy in the approaches considering torsion and not taking it into account is about 5% for all the samples studied in the work.

Flexural behavior of steel fiber reinforced concrete beams comprising coarse and fine rubber and strengthened by CFRP sheets

Despite having many advantages, using rubber to produce reinforced concrete members like beams is still restricted. When there is more waste tire rubber in concrete structures, rubber concrete's flexural and compressive strengths gradually decrease. However, this study used steel fibers to improve compressive strength and externally bonded carbon fiber-reinforced polymer (CFRP) sheets to increase flexural strength. Four groups of three reinforced concrete beams each were established for the study's use. The first and third groups of concrete beams used a volumetric replacement of fine and coarse aggregates with 5% and 10% waste tire rubber. However, steel fibers were added to the second and third groups at a rate of 1.25% of the concrete volume. Waste tire rubber and steel fibers were not replaced or added to the fourth group, the main reference group. The dimensions of each beam were 2.1×0.2×0.3 m. A concrete beam's first member is always free of external reinforcement, followed by its second member, which has one layer, and its third member, which has two layers of CFRP sheet. ABAQUS, a finite element analysis program, was used numerically to represent the third strengthening layer. The results showed that strengthening the reinforced rubberized concrete beams with a single layer of CFRP sheets increased the load at first crack and failure by 8.57% and 17.64%, respectively, compared to the unreinforced reference beam, compensating for the loss caused by the production of rubberized concrete and adding additional flexural strength. These loads increased by 31.43% and 26.45%, respectively, due to the steel fibers added to the beams containing these waste tire rubber. Strengthening with two layers of CFRP sheets increased the load at first crack and failure by 17.14 and 34.27, respectively. The steel fibers added to the beams that contained these amounts of waste tire rubber, on the other hand, caused these loads to increase by 42.86 and 49.23%, respectively. Strengthening with three layers numerically results in an exponential increase in load at the first crack and the failure by 8.03 and 52.88%, respectively. On the other hand, the loads on the beams that contained these quantities of waste tire rubber increased by 50.49% and 104.47%, respectively, when steel fibers were added to them.

Determination of Optimum Usage of Basalt in Strengthening of Concrete

Abstract: Strength is one of the most important properties of concrete and now a days different material are being used to enhance the strength property of concrete. The research aims to study the effect of basalt fibre on strength of concrete. M30 grade of concrete was used in this experiment. Basalt fibre were added in different proportion as 0%, 0.1%, 0.2% and 0.3 % by volume of concrete. Tests were conducted to determine the compressive strength , split tensile strength and bending strength of concrete. A gain in strength of concrete was observed when basalt fibre was used at 0.2% by volume of concrete

Construction aware optimization of concrete plate thicknesses

Concrete is a significant contributor to the global CO2 emissions, and therefore effort is being made to reduce its consumption in buildings and infrastructure. Since concrete flat slabs constitute most of the concrete in buildings, reducing their weight has great potential to reduce the overall environmental burden caused by buildings. In this study the authors develop an efficient, gradient-based thickness optimization framework for minimizing the concrete volume in concrete slabs, while insuring feasibility and constractability of the design. The results show that concrete savings of up to 35% are possible without increasing the structural depth, where in most cases minor increase in construction complexity is sufficient for significant concrete savings. Therefore, an appealing trade-off between the concrete savings, construction complexity, and architectural cost is revealed and can be used by engineers to reduce concrete consumption in buildings. The optimized thickness designs are not trivial and represent a balance between competing requirements that is obtained by the optimization algorithm, therefore the results demonstrate the potential of structural optimization as a design tool in structural engineering.

Investigating compressive strength of concrete containing steel fiber by data-driven approach

The main objective of this paper is to use the data-driven approach to predict and study the factors affecting the compressive strength of steel fiber concrete. Therefore, six machine learning (ML) models were evaluated against a database of 166 samples and ten input variables, including Cement content, Water content, Silica fume content, Steel fiber content, Coarse aggregate content, Sand content, Superplasticizer content, Fiber diameter, Fiber length, Fly ash content. SixMLmodels, including Artificial Neural Network (ANN), K-Nearest Neighbor (KNN), Categorical Boosting (CatB), Random Forest (RF), Gradient Boosting (GB), and Extreme Gradient Boosting (XGB), are evaluated against performance metrics and validated by 1000 Monte Carlo simulations. The compressive strength prediction performance by the ML models is arranged in descending order as follows XGB>GB>CatB>RF >ANN>KNN. The two best models can predict the compressive strength of steel fiber concrete to be GB with a coefficient of determination (R2) of 0.9874 and a root mean square error (RMSE) of 2.5763 MPa and XGB with an R2 of 0.9926 and an RMSE of 1.9814 MPa for the testing dataset. The influence of the ten variables can be arranged in descending order as follows: Cement content > Water content > Silica fume content > Steel fiber content >Coarse aggregate content > Sand content > Superplasticizer content > Fiber diameter > Fiber length > Fly ash content. Among them, Cement content, Silica fume content, and Steel fiber content have a positive effect on improving the compressive strength of concrete. The steel fiber content used should be less than 1.5% of concrete volume to improve the efficiency of steel fiber in concrete. Meanwhile, Fiber diameter and Fiber length have a minimal influence on the compressive strength of steel fiber concrete.

Potential Use of COVID-19 Surgical Masks and Polyethylene Plastics in Developing Sustainable Concrete

Managing disposable waste surgical face masks and plastic made from polyethylene (PE) resin is a real challenge. Thus, these are considered a great threat to the environment. Generally, surgical face masks are made of microplastic made of polypropylene materials. Both polypropylene and PE are not easily decomposable in the soil. Consequently, the presence of these waste materials can have detrimental effects on terrestrial and aquatic ecosystems, exacerbating the ongoing crisis faced by the animal kingdom and the broader biosphere. Hence, it is imperative to identify alternate and efficient methods for waste management. Given its significant economic importance, the construction industry holds a prominent position among many industries globally. Consequently, waste masks within the construction sector might assume a crucial role in mitigating plastic pollution. Concrete, one of the most widely used construction materials, is being adapted with various waste materials as the partial or complete substitutes for natural constituents, such as cement and aggregates. This study focused on using different percentages of used COVID-19 surgical masks in fiber form and PE as partial replacements of natural coarse aggregates in producing sustainable concrete. Mask fibers were used in concrete production at percentages of 0%, 0.5%, 1%, 1.5%, and 2% of the total volume of concrete. Similarly, PE aggregates replaced the coarse aggregates by volume at 0%, 5%, 10%, and 15% in concrete. The results showed that the strength of concrete reduced as the percentages of mask fiber and PE aggregates increased. However, the strength and crack-bridging capability of mask concrete are still acceptable for some structural and non-structural applications. The results obtained from this research could also help engineers to design sustainable concrete materials with mask fibers.

Accelerated carbonation of recycled concrete aggregates and its implications for the production of recycling concrete

During the demolition and recycling process the specific surface area per volume of concrete is significantly increased. As a result, the potential for CO2 absorption by carbonation of the cement hydrates is enhanced. In this study, recycled concrete aggregates (RCA) with varying moisture contents are carbonated with 100% CO2 at atmospheric pressure. The changes in the properties of RCA are characterized and they are used for the production of recycling concrete. There is only a minor impact of carbonation on bulk density and water adsorption of the RCA. The accelerated carbonation leads to the formation of calcium carbonate and decalcified calcium-silicate-hydrate (C-S-H) present in patches on the surface of RCA particles. Using slurry instead of tap water decreases concrete flow and generally increases compressive strength. Using carbonated instead of uncarbonated RCA leads to a faster decrease of flow with time and to a higher compressive strength of the recycling concrete compared to uncarbonated RCA. The higher strength linked to the use of carbonated RCA offers the potential to decrease the clinker content of the recycling concrete.

Comparative Cost and Design of Solid, Ribbed and Waffle Slab for a Three-storey Shopping Complex Using Prota, Orion and Spreadsheet

Cost is an important factor in choosing the type of floor or slab used in any construction. When a large space within a building needs to be covered without hindrance and supports, waffle or ribbed slabs are used. For all slab systems, the cost constitutes a significant portion of the overall cost of the structure. Therefore, this research aims to select a preferable slab system with the least construction cost for a shopping mall. Computer-aided design software such as Prota 2018 and Orion 2018 was used for analysis and design, and RCC spreadsheets were used to manually check the slabs. The results reveal that the Solid floor slab has more concrete volume and steel than the waffle, and the rib consumes the lowest least volume of concrete and steel among the three slab systems. Therefore, the rib slab is the most economical of the three slab systems since it uses the least concrete and reinforcement. The cost of a floor slab system ranges from 12 to 17% of the structural cost in building works, the percentages of the cost of the slab in a floor system is 17.84% for solid slabs system, 13.65% for rib slabs and 12.48% for waffle slabs of the total cost of a structure. It can therefore be concluded that using rib slab saves 17.95% and 7.46% of the construction sum when compared to solid slab and waffle slab construction systems respectively. In conclusion, it is recommended that ribbed slabs should be used for commercial building construction with more than 5KN/m2 live load in commercial buildings that spans up to 15m and more.

Effect of lightweight expanded clay aggregate as partial replacement of coarse aggregate on the mechanical properties of fire-exposed concrete

Abstract As aggregate material typically comprises 65–75% of concrete volume and has a significant effect on its mechanical properties, aggregate type considerably affects concrete behavior at high temperatures. In this study, 80 concrete cylinders and 60 cubes were cast to investigate the residual strength of normal concrete that contains lightweight expanded clay aggregate (LECA) with different volumetric replacement ratios (0, 10, 20, and 30%) of the coarse aggregate. After the fire flame exposure effect of steady-state temperatures (300, 400, 500, and 600°C), and a sudden cooling process, the mechanical tests (compressive strength, tensile strength, and modulus of elasticity; Ec), as well as mass loss and thermal conductivity, were carried out on the specimens. The results indicate that increasing the LECA content in the mixture leads to better strength retention after exposure to fire. After exposure to a steady-state temperature of 600°C, the amount of decrease in mass, residual compressive and tensile strengths, and the residual amount of Ec were 7.61, 7.5, 7.16, and 6.24%; 57.1, 66.8, 69.8, and 72.0%; 22.4, 32.7, 41.8, and 48.6%;, and 16.0, 22.3, 23.4, and 24.3%, respectively, for the considered volumetric replacement ratios of 0, 10, 20, and 30%. Also, the values of the thermal conductivity were 1.4889, 1.1667, 1.0912, and 1.0410 W/m K, respectively.

STRENGTH PROPERTIES OF HYBRID FIBRE REINFORCED CONCRETE USING FLY ASH

Concrete is strong in compression and weaker in tension. Therefore, to enhance the tensile strength of concrete certain fibres are added into the concrete. Fibre reinforced concrete (FRC) contains fibrous material, which increase the structural stability and integrity. Nowadays, hybrid fibre reinforced concrete (HFRC), which is the combination of various fibres into the conventional concrete makes it subtle and enhances the mechanical behaviour of the concrete. Aim of the study is to investigate the properties of hybrid steel and basalt fibres with and without fly ash for M25 grade of concrete. Four groups of mixtures containing fly ash (FA) contents of 0%, 10%, 20%, and 30% as cement replacement were produced with the inclusion of 0.50% steel fibres (SF) and 0.50% basalt fibres (BF) by volume of concrete. Fresh properties of mixtures were evaluated by using slump test, compaction factor and vee bee test. Hardened properties were tested at 28 days. Compressive strength, flexural strength, tensile strength, dry unit weight, porosity and water absorption were assessed. According to the results from the study, it is found that hybrid fibre reinforced concrete can act synergistically and increases the strength properties of concrete. The microcracks are checked to a larger extent. Key Words: Fly ash, Steel fibre and Basalt fibre