Concrete Technology Research Articles

Comparative analysis of ternary blended cement with clay and engineering brick aggregate for high-performance 3D printing

Utilising recycled brick aggregate in cementitious mixtures can decrease the overdependency on limited natural resources and improve the sustainability of concrete. This paper presents a potential solution to lower the amount of waste being landfilled and increase the sustainability of 3D concrete printing technology by combining low-carbon ternary blended cement with recycled aggregates. Hence, the effect of incorporating two types of recycled brick aggregate - clay brick (CBA) and engineering brick (EBA) on the properties of 3D printable ternary blended cement were investigated. The natural aggregate in a pre-existing 3D printable blend was substituted by up to 50 wt.-% with two varieties of recycled brick aggregates available throughout Europe. The recycled brick aggregates underwent characterisation to determine their properties. The fresh property evaluation using the green strength test was used to assess the effect of aggregate replacements on the mixture's shape stability. The mechanical performance of mixtures containing CBA and EBA, both cast and 3D printable mixes, was evaluated and compared to that of the control sample. The results indicated that incorporating recycled brick aggregate enhances green strength and Young's modulus significantly. Mechanical strength performance showed significant enhancement when incorporating RBA, which reached up to 67% and 55% for both cast and 3D printing methods, respectively. The suitability of the developed mix formulations for 3D printing was assessed by printing cylindrical objects.

Performance and mechanism of carbon sequestration of air-entraining wet shotcrete

CO2 curing concrete technology refers to the CO2 reacts with cement clinker minerals to obtain high-performance concrete and achieve the purpose of energy saving and emission reduction. The researches of air entrainment agent (AEA) focus on the development of new AEA and the study of concrete performance after adding some AEA. In the background of CO2 curing concrete technology, there are relatively few researches on the influence mechanism of different characteristics of bubbles introduced by different AEAs on carbon fixation performance of concrete. This paper demonstrates the characteristics of air bubbles introduced by SY-5 AEA (main component: triterpene saponin) and LAS AEA (main component: sodium dodecylbenzene sulfonate), compares the strength of concrete mixed with above two types of AEAs cured for 28 days and analyzed them by carbonization depth test, ultrasonic detection of fissure test, SEM, XRD and TG. Results show that different AEAs introduced different characteristics of air bubbles, which affected the internal pore characteristics of concrete, and then affected its mechanical properties and carbon sequestration properties. Compared with SY-5 AEA, LAS AEA had a slightly lower air-entraining effect. But the bubbles introduced were even and stable, the internal pores of the hardened concrete were uniform. Although the former had a high carbon sequestration, the latter had a higher intensity at 28 d, about 2.69 % higher. Under carbonization curing conditions, the improvement of concrete properties was more evident when appropriate AEAs were incorporated. The compressive strength and the splitting strength were increased by 5.57 % and 4.5 % respectively under the carbonization curing condition.

Review on solid wastes incorporated cementitious material using 3D concrete printing technology

The substitution of cement, natural sand, and synthetic fibers in concrete with solid wastes substantially reduces CO2 emissions. Incorporating solid wastes into 3D printed concrete, which reduces CO2 emissions from labor and formwork, can achieve innovative low-carbon construction materials. However, the previous studies lack a comprehensive review on the inherent characteristics of various solid wastes and their impacts on the printability, mechanical performance, and functionality of 3D printed concrete. This paper reviews the present state of research and introduces feasible methods for the sustainable use of solid wastes in 3D printed concrete. Numerous types of solid wastes are investigated comprising their benefits, shortages, and fit dose to guide in selecting the optimal solid waste to enhance the performance of printed concrete. Additionally, the printability, functionality, and mechanical strength of printed concrete with solid waste addition are quantified and summarized. The preliminary exploration to achieve a balance between multi-functionality and mechanical properties using mixed solid wastes is conducted for 3D concrete printing. Finally, machine learning, broadening raw material sources, automated monitoring systems, multi-functionalized composite, and BIM are proposed to address current challenges.

Influence of Percentage Glass Fiber Reinforcement on Flexural Strength

Today's globe is seeing the creation of extremely complex and demanding civil engineering facilities. Being the most significant and commonly utilized material, concrete is frequently required to have extremely high strength and adequate workability qualities. In the field of concrete technology, attempts are being undertaken to create such concretes with unique qualities. Researchers worldwide are working to use fibers to create high-performance concretes. and other additives in concrete up to a specific percentage. This paper attempts to study the influence of the rate of glass fiber reinforcement in concrete on flexural strength. UTM tests are carried out to measure the strength of glass fiber- reinforced concrete beams. It was observed that there is considerable improvement in the flexural strength after adding glass fiber to concrete. Key Words: GFRC, Flexural Strength

Aluminate 2K systems in digital concrete: Process, design, chemistry, and outlook

Digital concrete is advancing due to growing economic incentives for construction automation. Achieving more sustainable concrete construction requires carbon reduction, and digital concrete technologies enable material-saving designs. By decoupling production strength from design strength, two-component (2K) systems utilizing aluminate precipitation offer the most flexibility, allowing more sustainable mixes with higher substitution levels. However, 2K aluminate systems are complex and demand a deeper understanding of their chemistry and strength buildup. This article reviews the basics of 2K aluminate systems, specifically aluminum sulfate-based and calcium aluminate cement/calcium sulfate-based systems, and their use in an inline active mixing reactor. An example reaction engineering analysis predicts the degree of reaction in a given reactor design, relating it to yield stress. The two chemical systems are compared, and future research recommendations are provided.

Feasibility of underwater 3D printing: Effects of anti-washout admixtures on printability and strength of mortar

The dispersion and reduction in strength of concrete underwater pose significant challenges to advancing underwater 3D concrete printing technology. While employing anti-washout admixtures holds promise, there is a dearth of relevant research. Herein, a study using various potential anti-washout admixtures, such as micro silica (MS), nano silica (NS), glass fibers (GF), and hydroxypropyl methyl cellulose (HPMC), in mortar mixes was conducted. These mortar mixes were then printed underwater, and their performance in both fresh and hardened states was evaluated to develop underwater 3D printable mortars. The findings revealed that both MS and NS enhance the washout resistance, extrudability, and buildability of fresh mortar, while also improving the flexural, compressive, and bond strengths of hardened mortar. HPMC enhances underwater printability and bond strength, although it may negatively impact flexural and compressive strengths. GF exhibits adverse effects on underwater printability and mechanical properties and is incompatible with HPMC. Noticeably, the combination of MS, NS, and HPMC greatly enhances underwater printability (no dispersion and lowest extrudability/buildability variation coefficients) and mechanical properties (increasing flexural strength and bond strength by 21 % and 151 %, respectively). These findings led to the proposal of several mortar mixes deemed suitable for underwater 3D printing.

Study on the mixed fracture characteristics of concrete-rock Brazilian disks with different fracture angles

The fracture characteristics of cracked straight-through Brazilian discs for concrete-rock composites (CSTBD-CRC) with different fracture inclination angles (Mode I-II) were investigated to evaluate the stability of concrete reinforcement engineering. Acoustic emission (AE) and digital image correlation (DIC) techniques were employed to study crack propagation and fracture modes in CSTBD-CRC Brazil splitting tests, as well as the entropy evolution of AE and DIC. Additionally, 3D scanning technology and fractal theory were utilized to investigate the effect of the fracture mode on the fracture surface morphology. The results indicate that both the fracture energy and peak load of the CSTBD-CRC increase with increasing fracture inclination angle. Moreover, the section fractal dimensions of 0°, 10°, 15° and 25° samples are 2.01879, 2.01528, 2.01186, and 2.01072. Shear fracture mode increases as the dip angle increases and the fracture surface morphology decreases in fractal dimension. Notably, sharp increases in entropy values for both AE and DIC occurred at peak load, suggesting their use as failure criteria for CSTBD-CRC specimens. Furthermore, cracks were found to initiate at the tips of preexisting cracks within the concrete. The displacement in the x direction undergoes the most significant changes on both sides of the crack during crack growth, while the strain in the x direction experiences its greatest variations at the crack location.

Modeling of effect of fly ash amount on microstructure and chloride diffusivity of blended fly ash-cement systems

Reasonable utilization of industrial fly-ash wastage in concrete engineering has been regarded as an effective way to reduce carbon emissions. By adding the reasonable dosage of fly ash to cement paste, the compactness and microstructure characteristics of the blended cement systems can be significantly improved, thereby effectively enhancing the durability of concrete structures. The vector hydration model of blended fly ash-cement systems with the interference effects of different hydration layers of fly ash and cement particles, the solubility equilibrium of solid phases and the electrical neutrality of the pore solution involved is established. By fully comparing with the experimental data of hydration degree, capillary porosity and CH content, the accuracy of the developed hydration model is verified. Based on the hydration model, the effect of fly ash content on the concentration of different ions and pH in the pore solution with curing time is discussed. Additionally, the evolution characteristic of hydration degree, capillary porosity and CH content with curing time at different fly ash content is also analyzed. Based on the reconstructed microstructure of blended systems, the rolling sweep (RS) technique is used to determine the pore size distribution of capillary pores. The effect of fly ash content on cumulative pore size distribution and differential pore size distribution at different curing time is quantitatively evaluated and discussed. By utilizing the first-passage cube, the dual-probability-Brownian motion method is constructed to predict the chloride diffusivity of blended cement systems. After diffusion model is verified by multi-group experimental data, the optimal dosage of fly ash at different water-binder ratio is calculated, which can provide theoretical guidance for practical applications in concrete engineering.

Acid rain resistance of geopolymer recycled pervious concrete featuring top-bottom interconnected pores under freeze-thaw cycles and fatigue loads

While pervious concrete with top-bottom interconnected pores enhances the performance of pervious concrete pavements, its resistance to acid rain under combined freeze-thaw cycles and fatigue loads remains unexplored. To fill this gap, this study investigated the influence of three different qualities of recycled coarse aggregates on the acid resistance, acid neutralization, and permeability of geopolymer recycled pervious concrete (GRPC) (Low-quality, middle-quality and high-quality geopolymer recycled pervious concrete (L-GRPC, M-GRPC and H-GRPC)) under the couple effects of simulated acid rain wet-dry cycle spraying, fatigue loads and freeze-thaw cycles. After experiencing the combined action of fatigue load and freeze-thaw cycle, only the compressive strength of L-GRPC increased slightly by 9.1 % after acid rain spraying, but it had a negative impact on the flexural strength. With the increase of coupling environmental factors, the neutralization depth of GRPC was less than 4 mm, and the permeability coefficient was higher than 0.5 mm/s. Furthermore, more gypsum crystals were observed in the SEM images, and new peaks corresponded to the gypsum phase (CaSO4) appeared at 2θ = 29.4° and 2θ = 21.6° in the XRD spectra. The research results provide a broader perspective for the application of GRPC in concrete pavement engineering in acid rain area.

Full-scale testing and multiphysics modeling of a reinforced shot-earth concrete vault with self-sensing properties

Abstract Civil constructions significantly contribute to greenhouse gas emissions and entail extensive energy and resource consumption, leading to a substantial ecological footprint. Research into eco-friendly engineering solutions is therefore currently imperative, particularly to mitigate the impact of concrete technology. Among potential alternatives, shot-earth-concrete, which combines cement and earth as a binder matrix and is applied via spraying, emerges as a promising option. Furthermore, this composite material allows for the incorporation of nano and micro-fillers, thereby providing room for enhancing mechanical properties and providing multifunctional capabilities. This paper investigates the damage detection capabilities of a novel smart shot-earth concrete with carbon microfibers, by investigating the strain sensing performance of a full-scale vault with a span of 4 m, mechanically tested until failure. The material’s strain and damage sensing capabilities involve its capacity to produce an electrical response (manifested as a relative change in resistance) corresponding to the applied strain in its uncracked state, as well as to exhibit a significant alteration in electrical resistance upon cracking. A detailed multiphysics numerical (i.e. mechanical and electrical) model is also developed to aid the interpretation of the experimental results. The experimental test was conducted by the application of an increasing vertical load at a quarter of the span, while modelling of the element was carried out by considering a piezoresistive material, with coupled mechanical and electrical constitutive properties, including a new law to reproduce the degradation of the electrical conductivity with tensile cracking. Another notable aspect of the simulation was the consideration of the effects of the electrical conduction through the rebars, which was found critical to accurately reproduce the full-scale electromechanical response of the vault. By correlating the outcomes from external displacement transducers with the self-monitoring features inherent in the proposed material, significant insights were gleaned. The findings indicated that the proposed smart-earth composite, besides being well suited for structural applications, also exhibits a distinctive electromechanical behavior that enables the early detection of damage initiation. The results of the paper represent an important step toward the real application of smart earth-concrete in the construction field, demonstrating the effectiveness and feasibility of full-scale strain and damage monitoring even in the presence of steel reinforcement.

Optimization of Styrofoam as Concrete Replacement Material Subjected to Compressive Strength

Nowadays, the construction sector is developing rapidly, and there is an increase in demand for innovative concrete technology. This is because concrete has many advantages over other building materials. Improving the quality of concrete can be done by providing replacement materials or adding several replacement materials, and one of the alternative materials that can be used is styrofoam. The purpose of this research is to evaluate the effect of styrofoam as high-quality concrete and compare the compressive strength between control concrete by using 1%, 2%, and 3% ratios of styrofoam. The experimental method is applied in this research, experiment was conducted and tested in accordance with SNI 03-6468-2000. The results of the study show that the compressive strength of styrofoam mixed concrete using ratios of 1%, 2%, and 3% obtained 23,30 MPa, 17,34 MPa, and 11,64 MPa. The results showed that Styrofoam replacement was used for K.350 high-strength concrete. It is not recommended for building or bridge construction because the compressive strength test results produced are meagre compared to standard concrete without a mixture of styrofoam. After all, the mass of concrete mixed with styrofoam is lighter than normal concrete so that it can be used for construction with low loads.

Multisource ultrasound-excited thermography for detecting concrete microcracks in hydraulic structures

ABSTRACT Hydraulic concrete structures often suffer from cracking that could lead to engineering accidents. Thus, it is important to identify emerging concrete cracks so that the premonitory danger of the components can be comprehensively evaluated, and the disaster management level can be advanced to the initial stage of the hazard. This study investigated the use of ultrasound-excited thermography to detect surface microcracks in concrete engineering components. A detection system and method for the synergistic excitation of multiple excitation sources were developed, and self-adaptive pressure-loading sleeves containing back shafts made of glass fibre-reinforced nylon were developed to exert pressure on the transducers. Eighteen groups of in-situ experiments were conducted on important parts of the key component using a combination of 28-kHz and 40-kHz-transducers with a power of 100 W. The results demonstrate that ultrasound-excited thermography with the synergistic excitation of multiple excitation sources can be applied to detect surface cracks in approximately semi-infinite reinforced concrete members in-situ. The radius of the current investigation of cracks stimulated by one 100-W transducer pressed by the self-adaptive sleeve in reinforced concrete members is as far as 300 mm. The minimum widths of the detected cracks are 0.03 mm.

Combining BioTRIZ and Multi-Factor Coupling for Bionic Mechatronic System Design

To realize the design process of bionic mechatronic systems, involving mapping from engineering to biology and inversion from biology to engineering, a novel design paradigm is introduced that integrates BioTRIZ with multi-factor coupling bionics. In the mapping stage from engineering to biology, BioTRIZ is employed to frame the concrete engineering issue as a general conflicting problem. The biological solution is refined by amalgamating the BioTRIZ solution derived from the contradiction matrix with biological instances. In the inversion stage of biology to engineering, a novel approach is proposed for constructing a bionic multi-factor coupling model, drawing inspiration from the establishment of biological multi-factor coupling model. This allows for a seamless correspondence between biological elements, such as morphology and behavior, and their respective engineering counterparts, including structure and algorithms. This correspondence ultimately achieves the engineering conceptual model that is rooted in biological principles. The practical application of this methodology is exemplified through a multi-biometric fusion bionic active vision system, underscoring its feasibility and efficacy.

Advances and Significances of Nanoparticles as Concrete Additives: A Comprehensive Review

Nanotechnology, a significant technological advancement in the current century, has brought about revolutionary changes in numerous fields by manipulating matter at the nanoscale. This review paper examines the various applications of nanoparticles in the concrete industry, emphasizing their potential to improve mechanical qualities, thermal performance and sustainability. This study investigates multiple synthesis strategies, such as grafting, sol–gel, chemical and biological procedures, which offer concrete engineers a diverse range of options to tailor the properties of nanoparticles. The utilization of this particular material results in notable enhancements in many mechanical properties of concrete, including its compressive and flexural strength, toughness, thermal conductivity and self-sensing capabilities. These improvements ultimately contribute to the overall enhancement of the concrete’s structural integrity and energy efficiency. Adding nanoparticles to concrete has also been shown to help it develop self-healing properties. This means that structures last longer and require less maintenance. Making building materials more resistant to chemical corrosion, wear and environmental forces is also a big step in making them last longer. The growing emphasis on sustainability within the building industry has generated heightened attention toward utilizing self-healing concrete, which frequently incorporates nanoparticles. To make the building industry more environmentally friendly, using less traditional cement and recycling personal safety equipment (PPE) like vinyl and latex gloves can help protect the environment. This review also highlights the significant problems in employing nanoparticles in concrete: obtaining equal dispersion, handling-costs and addressing environmental and health concerns. However, nanotechnology is advancing construction concrete research to improve mechanical properties and durability.

A Comprehensive Review on Effects of Material Composition, Mix Design, and Mixing Regimes on Rheology of 3D-Printed Geopolymer Concrete

Recent years have witnessed a significant growth in the research and development of additive manufacturing methods involving concrete and cementitious materials, with technologies like three-dimensional (3D) printing becoming more widely used in the construction industry. Construction has the possibility to be revolutionized, not only in the context of cost savings but also in the context of increased sustainability and functionality. 3D printing of concrete is a cutting-edge technology that has the potential to speed up construction, reduce labor costs, give architects more creative freedom, improve precision, obviate requirements for formwork, and result in less construction wastes. In addition, 3D printing can be a long-term solution for both economy and environment. Even though 3D printing in concrete has made tremendous strides recently, developing an effective 3D-printable material that decreases material usage and enhances performance is critical for carbon dioxide reduction. Robust geopolymer formulations for 3D printing concrete technology in current construction applications have emerged as the subject of much research among scientists to find novel ways to circumvent this constraint. This study intends to highlight the current state of the art in developing 3D-Printed Geopolymer Concrete (3DPGC) with a comprehensive review related to the material composition, mix design, and mixing regimes on rheology of 3DPGC. The rheology of 3DPGC in terms of printability and buildability is discussed. The mixing regimes employed for the preparation of one-part and two-part 3DPGC are tabulated and commented on. Lastly, the research gaps are identified and summarized, and several research directions are also provided for future investigations to expedite the ubiquitous use of 3DPGC in versatile construction applications.

Repair of Underwater Concrete Cracks on Dam Surface: Optimization Analysis of the Grouting Process with Surface Sealing.

The grouting repair process of the sealing baffle on the surface of dam cracks can improve the repair slurry diffusion distance in the cracks; however, the process must be optimized. To address the problem of crack repair technology of underwater dam concrete with one section open and the other closed, a grouting analysis model was established. By adjusting various parameters in the grouting process, the influences of the grouting pressure, position of the grouting hole, diameter of the grouting hole, and water pressure on the diffusion of the Bingham fluid repair slurry in these cracks were studied. The results show that the grouting pressure and diameter of the grouting hole significantly influence the limited diffusion distance of Bingham fluid cement slurry in cracks. With an increase in grouting pressure and grouting hole diameter, the limiting distance of the front surface increases. The influences of the water pressure and position of the grouting hole are small. In addition, through correlation analysis, the degrees of influence of different factors can be sorted, providing the priority factors for actual operation construction.

An Integrated T-Spherical Fuzzy Einstein Interaction Aggregator Group Decision-Making Approach: A Case Study of Concrete 3D Printing Robot Application in Vietnam

This study introduces the integrated T-spherical fuzzy Einstein interaction aggregator group decision-making approach, a novel framework designed to enhance multi-criteria decision-making (MCDM). Implementing the case study of concrete 3D printing technology in Vietnam, this approach integrates T-spherical fuzzy sets with Einstein aggregation operators to handle the complexities of uncertain and subjective expert judgments effectively. The methodology provides a robust mechanism for evaluating and prioritizing the barriers and strategies associated with the implementation of concrete 3D printing. Findings from this study underline the significance of technological advancements and strategic financial incentives, with R&D strategy emerging as the top priority. This research contributes to both theoretical advancements in decision-making frameworks and offers practical insights for industries looking to integrate emerging technologies. Moreover, it demonstrates the application of advanced fuzzy set theories in real-world settings, providing a valuable tool for decision-makers facing similar technological adoption challenges.

Chemical shrinkage, autogenous shrinkage, drying shrinkage, and expansion stability of interfacial transition zone material using alkali-treated banana fiber for concrete

ABSTRACT It might be of interest for authors to learn more that in the early 1900s, fibers were used in cement-based material, as cement-based materials exhibit shrinkage cracking over time, which can be controlled by adding fibers. The main aim of the inserting natural fiber into cement-based material is to decrease the shrinkage of cement-based material, prevent the rising of shrinkage cracks, and develop low-cracking cement-based material. In the research, the same aim aforementioned was kept same way. For carrying out the aim, agricultural waste, known as banana fiber (BF), can be considered a shrinkage reducer, expansion stabilization, a renewable material and has potential to make cement-based material transformed into a green construction material. This research investigated the effect of BF incorporation on cement paste shrinkage. Thus, five mixes were developed with different BF additions based on the total volume of cement paste (0, 0.5, 1, 1.5 and 2%). For each mixture, four tests were carried out to assess the impact of BF addition on the paste’s volume stability: chemical, autogenous, drying shrinkage and expansion. Testing was conducted for up to 90 days. Compared to the control mix, the addition of 2% BF reduced chemical shrinkage, autogenous shrinkage, drying shrinkage, and expansion by 27%, 57%, 47%, and 66%, respectively. Furthermore, a positive correlation was observed between chemical shrinkage and both autogenous and drying shrinkage and the percentage of BF content. Conversely, there was an inverse relationship between chemical shrinkage and expansion. The most significant conclusion to emerge from this study is that the incorporation of banana fiber (BF) into alkali-treated concrete results in a reduction in chemical shrinkage, autogenous shrinkage, drying shrinkage, and expansion. This is attributed to the molecular structure of BF, which is characterized by uninterrupted glycosidic linkages, leading to alkaline breakdown within the alkaline environment. Consequently, the alkali-treated BF can be described as a volume stability admixture in concrete technology.

Detecting Cracks in Intelligent Carbon-Based TRC Elements Through Wetting Events

Textile reinforced concrete (TRC) technology enables to construct sustainable and environmentally friendly thin-walled structural elements with self-sensory capabilities. The self-sensory concept is based on using high-strength and electrically conductive yarns that are simultaneously used as the main reinforcement system and as the sensory agent. By connecting the two ends of the yarns to either direct current (DC) or alternating current (AC) electrical circuits, it is possible to measure changes in the electrical readings and to further correlate them to the structural health. Studies in the literature validated the concept by using carbon yarns as hybrid monitoring agents. Most of them provided integrated assessments of global structural health but lacked the capability to pinpoint individual cracks. The current study offers a new identification procedure to locate cracks and to estimate their severity by combining two advanced monitoring procedures, that is by adopting the Time Domain Reflectometer (TDR) analysis; and by conceptually using the smart water leakage detection method. Both methods take advantage that a pair of carbon yarns can be positioned parallel to each other and connected to the DAQ system. In case of TDR method, one yarn functions as the signal transmitter and the other as insulation. In case of water leakage detection method, the electrical linkage between the two yarns changes the electrical characterization of the electrical circuit and enables the monitoring capabilities. The proposed study argues that a new identification procedure that benefits from each method can be developed and yields to smart identification procedure that has the capability to locate the crack and estimate its severity. The study will demonstrate the feasibility of the new procedure by experimental study. Results from this study will take a significant step toward developing reliable smart carbon-based TRC structures.

The Effect of Rice Husk Ash as Cement Substitution on the Compressive Strength of Self-Compacting Concrete

Self-Compacting Concrete (SCC) is an innovative solution in today's world of concrete technology. Unlike traditional concrete, it does not require a vibrator for compaction, which makes concrete work easier. One of the key features of SCC is its high workability, which is achieved through the use of chemical admixtures and mineral additives. Rice husk ash is one such additive that can be used as a pozzolanic material for concrete mixtures, which is important as rice husk waste can cause environmental problems. The objective of this study was to investigate the effect of rice husk ash on SCC concrete. The study involved using Rice Husk Ash (RHA) as a partial replacement for cement in SCC concrete at varying percentages (0%, 5%, 10%, and 15% of cement weight). The results of the slump flow test showed that the highest value of 775 mm was achieved at 15% RHA, meeting the specifications of SCC concrete. In terms of compressive strength, the results showed that the SCC mixture without rice husk ash (0% RHA) had the highest average compressive strength, which was 30.56 MPa at 14 days and 31.66 MPa at 28 days of concrete. On the other hand, the average compressive strength of SCC concrete with rice husk ash mixture was highest at 5% RHA, with 25.04 MPa at 14 days and 28.81 MPa at 28 days. Overall, the study found that the use of rice husk ash in SCC concrete had a significant effect on its compressive strength, with the highest compressive strength being achieved at 5% RHA.