Research on Cost-Effectiveness Analysis of Concrete Materials Based on Optimization Algorithm

This study examined the application of pulverize clay brick wastes as alternative constituent for Portland cement replacement in green concrete production using the response surface methodology (RSM). The adopted response surface approach is central composite design (CCD). The statistical models were developed between the concrete constituents (clay brick powder and water cement ratio) and their response variables (slump, compressive and split tensile strength). Relationships were established and mathematical models in terms of actual factors from predicted responses were developed. The influence of the considered factors on the properties of response were visually observed from the contour and response surface plots. The statistical models of experimental values clearly depict that the obtained experimental values are in close agreement with the predicted values, which validates the response surface models with desirability value of 1. The results show that pulverized clay brick waste have significant influence on the properties of concrete than the water cement (w/c) ratio, however, a declining trend was seen for all analyzed concrete properties. In addition, this study showed that the pulverized waste brick can be used as alternative substitute for Portland cement up to 20% in the production of sustainable concrete.

Cement mortar or slurry is an essential material for production of Slurry Infiltrated Fibrous Concrete (SIFCON) structural components. However, there have been limited technical data available for deciding a suitable mix proportions and water cement ratio. For achieving a good quality of mortar mix or slurry with specific strength requirement and satisfactory level of workability for proper infiltration ability of cement slurry fibrebed. The preliminary study was carried out to select suitable mix and W/C from various mixes (1:1, 1:1.5 &1:2) and W/C (0.4, 0.45 & 0.5)on fresh and hardened properties of cement mortar. The optimum mix proportion and water cement ratio were obtained on workability (flow table test) and compressive strength of cement mortar are found to be as 1:1 and 0.40 respectively for fabrication of SIFCON. The main focus of this investigation on the behaviour of SIFCON contains various volume fraction of fibre content with an optimum mix(1:1) and W/C (0.4) under static loading. Hooked end steel fiber length of 30mm and tensile strength of 1050MPais used throughout the entire investigations. Cubes of 100 x 100 x 100mm for compressive strength and cylinders of 100mm diameter and 200mm height for split tensile strength were cast and tested at 3, 7 and 28 days. For flexural strength, three SIFCON beams of length 1200mm and cross section of 100mmx 200mm were cast and tested at 28 days under three point bending. The parameters like fracture energy, load deflection response, split tensile strength and compressive strength were found and compared the results with conventional mix. The test results observed that the strength performances were greatly improved due to addition of fibre by volume fraction in SIFCON matrix. Also developed the regression model from the experimental results to estimate the compressive and split tensile strength and compared the predicted values with the experimental values.

The properties of concrete containing coarse recycled aggregates were investigated. Laboratory trials were conducted to investigate the possibility of using recycled aggregates from the demolition wastes available locally as the replacement of natural coarse aggregates in concrete. A series of tests were carried out to determine the density, compressive strength, split tensile strength, flexural strength and modulus of elasticity of concrete with and without recycled aggregates. The water cement ratio was kept constant for all the mixes. The coarse aggregate in concrete was replaced with 0%, 20%, 40%, 60%, 80% and 100% recycled coarse aggregates. The test results indicated that the replacement of natural coarse aggregates by recycled aggregates up to 40% had little effect on the compressive strength, but higher levels of replacement reduced the compressive strength. A replacement level of 100% causes a reduction of 28% in compressive strength, 36% in split tensile strength and 50% in flexural strength. For strength characteristics, the results showed a gradual decrease in compressive strength, split tensile strength, flexural strength and modulus of elasticity as the percentage of recycled aggregate used in the specimens increased. 100% replacement of natural coarse aggregate by recycled aggregate resulted in 43% savings in the cost of coarse aggregates and 9% savings in the cost of concrete.

Currently, the concrete structure is being developed using alternative materials, and the strength properties of the concrete have improved in various aspects. The coarse particles are removed from the concrete and the fine particles in the concrete. It tends to improve the mechanical and durability properties of the concrete in different environmental conditions. This research examined the mechanical and durability properties of the Reactive Powder Concrete (RPC) under environmental conditions. This study’s primary objectives were to evaluate the RPC’s compressive, split tensile and flexural strength. Additionally, the durability properties of the RPC were examined in various immersion conditions. The RPC is investigated by incorporating the glass fibre in various percentages of 0.1%, 0.2%, 0.3% and 0.4%, respectively. The optimum glass fibre 0.75% enhanced the mechanical properties of the RPC by 15%, 24% and 27% for compressive, split tensile and flexural strength compared to the conventional RPC mix. The durability properties of the RPC were improved by 23% compared to the conventional RPC mix subjected to acid resistance. Furthermore, microstructural analyses such as SEM and EDAX were evaluated for both the conventional and optimum mixes of RPC. These analyses help to examine the morphology and chemical components of RPC. Linear regression analysis was performed in this study to predict the mechanical properties of RPC. The relationships between compressive and split tensile strength, as well as compressive and flexural strength, showed a high correlation with the experimental results. The linear regression coefficient (R2) is 0.96 for compressive and split tensile strength and 0.97 for compressive and flexural strength. This research can be recommended for practical applications in developing sustainable structures.

This paper presents the result of the regression modeling of the strength properties of hybrid fiber reinforced concrete made with polypropylene fiber (PPF) and alkali resistant glass fibre (ARGF). The fibres were added to grade 25 concrete at different proportion of 0.5%, 1.0%, 1.5% and 2.0% of volume of concrete. A total of sixty three cubes samples were tested for compressive strength, twenty four cylindrical samples for split tensile strength and twenty four beam samples for flexural strength. Maximum compressive strength was attained at 1.5% fibre volume with hybrid fibre ratio of 80% ARGF and 20% PPF, maximum split tensile strength was attained at 1.0% fibre volume with hybrid fibre ratio of 80% ARGF and 20% PPF. The beam samples attained its maximum flexural strength at 1.0% fibre volume with hybrid fibre ratio of 60% ARGF and 40% PPF. Empirical expressions were established by using multiple regression analysis to predict the compressive, split tensile and flexural strengths of the hybrid fibre reinforced concrete made with PPF and ARGF. The predicted values compared favourably with the experimental results from all specimens.Keywords: alkali resistant glass fibre, compressive strength, flexural strength, hybrid fibre concrete, polypropylene fibre, regression modeling. reinforced concrete, split tensile strength

In this paper, the effects of different influencing factors and factor interaction on the compressive strength and permeability of recycled aggregate pervious concrete (RAPC) were studied based on the response surface method (RSM). By selecting the maximum aggregate size, water cement ratio and target porosity as design variables, combined with laboratory tests and numerical analysis, the influences of three factors on the compressive strength and permeability coefficient of RAPC were revealed. The regression equation of compressive strength and permeability coefficient of recycled aggregate pervious concrete were established based on RSM, and the response surface model was optimized to determine the optimal ratio of RAPC under the conditions of meeting the mechanical and permeability properties. The results show that the mismatch item of the model is not significant, the model is credible, and the accuracy and reliability of the test are high, but the degree of uncorrelation between the test data and the model is not obvious. The sensitivity of the three factors to the compressive strength is water cement ratio > maximum coarse aggregate particle size > target porosity, and the sensitivity to the permeability coefficient is target porosity > maximum coarse aggregate particle size > water cement ratio. The absolute errors of the model prediction results and the model optimization results are 1.28 MPa and 0.19 mm/s, and the relative errors are 5.06% and 4.19%, respectively. With high accuracy, RSM can match the measured results of compressive strength and permeability coefficient of RAPC.

Marble stones are one of the famous mining products in Tulungagung Regency and have quite a large amount. This matter makes the marble stones produce quite a lot of waste and pollutes the environment. That, necessary wastes treatment process to reduce environmental pollution by making sands substitution in normal concrete. This research aims to know the effect of substitution marble stones to value of compressive strength and split tensile strength at variations of 0%, 10%, 20%, 30% & 40% and calculate the number of costs needed with the purpose to obtain more economical cost. The mix design of normal concrete use SNI 03-2834-2000 with quality 20 MPa. Then, to know the effect of compressive strength and tensile strength use the Anova test. Based on the result obtained the biggest average compressive strength value at 28 days old is a variation 40% by 54,07 MPa and the smallest is a variation 10% by 19,29 MPa and compressive strength that meets the margin value of the mix design is a variation of 0% of 24.37 MPa; 30% of 25.82 MPa; & 40% in the amount of 42.07 MPa. While the result for the biggest average tensile strength value at 28 days old is a variation of 40% by 3,07 MPa and the smallest is a variation of 20% by 1,49 MPa. Based on the result Anova test for compressive strength and split tensile strength can't be done. So that, used the Kruskal Wallis test and obtained results for compressive strength that marble stone wastes to affect compressive strength. While for split tensile strength declare that marble stone wastes can't affect split tensile strength. In the cost of the calculations on each variation tends to decrease with the lowest cost which is obtained in variation 40% is amount Rp 1.366.696 and save 4,30% from the cost in concrete variation 0%. Then, for financially feasible study for value NPV worth Rp 2.233.637.768 and BCR worth 1,03. So, this business stated feasible for implementation.

Concrete is a widely utilized construction material globally; however, it is characterized by a fundamental deficiency in its tensile strength when it is not reinforced. The incorporation of diverse novel materials into concrete is being pursued with the aim of mitigating its limitations while concurrently enhancing its reliability and sustainability. Furthermore, it is noteworthy that concrete embodies a significant quantity of carbon. The primary cause of this phenomenon can be attributed to the utilization of cement as the principal binding component in concrete. Recent advancements in research have indicated that jute fiber, commonly referred to as JF, exhibits considerable potential as a novel material for enhancing the mechanical robustness of concrete. Although there is a significant body of literature on the application of jute fiber in concrete, there has been a dearth of research on the capacity of jute fiber (JF) to improve the mechanical strength of concrete and mitigate its carbon emissions. This study aims to cover a gap in the existing literature by analyzing and enhancing the application of JF in relation to its mechanical properties and environmental impact. The study involved conducting experiments wherein JF was added at varying weight percentages, specifically at 0%, 0.10%, 0.25%, 0.50%, and 0.75%. The investigation encompassed a number of examinations of both the fresh and hardened states of concrete, in addition to assessments of its durability. The fresh concrete tests included the slump test, while the hardened concrete tests involved measuring compressive strength (CS), split tensile strength (STS), and flexural strength (FS). Additionally, the durability tests focused on water absorption (WA). The study involved the computation of embodied carbon (EC) ratios for various mix combinations. The findings suggest that incorporating JF into concrete results in a decrease in environmental impact relative to alternative fiber types, as demonstrated by a rise in eco-strength efficiency (ESE). Based on the findings of the conducted tests, an optimal proportion of 0.10% JF has been determined to be conducive to enhancing the CS, STS, and FS by 6.77%, 6.91%, and 9.63%, respectively. The aforementioned deduction can be inferred from the results of the examinations. Using data obtained from extensive experimentation, the RSM (Response Surface Methodology) was used to construct a model. The model was optimized, resulting in the establishment of definitive equations that can be used to evaluate the effects of incorporating JF into concrete. Potential benefits have been identified for the advancement of concrete in the future through the utilization of JF.

PurposeSelf‐compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers bridge cracks, retard their propagation, and improve several characteristics and properties of the SCC. The purpose of this paper is to investigate the effects of type and volume fraction of steel fiber on the compressive strength, split tensile strength, flexural strength and modulus of elasticity of steel fiber reinforced self‐compacting concrete (SFRSCC).Design/methodology/approachFor this purpose, Micro wire and Wave type steel fibers with l/d ratios of 50 were used. Three different fiber volumes were added to concrete mixes at 0.5, 0.75 and 1 per cent by volume of SCC. Six different SFRSCC mixes were prepared. After 28 days of curing, compressive, split and flexural strength and modulus of elasticity were determined.FindingsIt was found that, inclusion of steel fibers significantly affect the split tensile and flexural strength of SCC accordance with type and vf. Besides, mathematical expressions were developed to estimate the flexural, modulus of elasticity and split tensile strength of SFRSCCs regarding of compressive strength.Originality/valueIt was found that inclusion of steel fibers significantly affected the split tensile and flexural strength of SCC accordance with type and f v.

Traditional concrete, made from binding material, fine aggregate, coarse aggregate, and water, often suffers from low tensile strength and susceptibility to cracking. Microscopic cracks can develop before any significant load is applied, making the structure vulnerable to damage. Fiber reinforced concrete (FRC) tackles these issues by adding different types of fibers, like steel, glass, and polypropylene, to enhance strength and flexibility. This study aims to find the best mix for Steel Fiber Reinforced Concrete (SFRC) and Hybrid Fiber Reinforced Concrete (HFRC) of M25 grade. Compressive strength, split tensile strength, flexural strength, Young's modulus, and ultrasonic pulse velocity tests are conducted to see how well the fibers work to prevent cracks and boost strength. Results have showed that SFRC with 1.5% steel fiber content significantly improve compressive strength, split tensile strength, and flexural strength compared to normal concrete. Similarly, HFRC mix of steel, glass, and polypropylene fibers, performs well, showing a notable increase in split tensile and flexural strength. The percentage increase in strength highlights how effective fiber reinforcement can be, with HFRC showing better results in some aspects compared to SFRC. Furthermore, both SFRC and HFRC are stiffer than normal concrete, indicating better overall structural integrity. Our comparison suggests that incorporating a blend of fibers, as seen in HFRC, can provide even better results, particularly in enhancing split tensile and flexural strength, showing promise for future reinforced concrete applications.

Limited studies have been conducted on low-aluminum and rich-iron-calcium fly ash (LARICFA)-based geopolymer concrete with increased strength. This study aims to investigate the mechanical characteristics of LARICFA-based geopolymer concrete, including its compressive strength, split tensile strength, and ultimate moment. The steps of this study include material preparation and testing, concrete mix design and casting, specimen curing and testing, and the analysis of testing results. Furthermore, the specimen tests consist of the bending, compressive, and split tensile strength tests. The results show that the average compressive strength and the ultimate moment of the geopolymer concrete are 38.20 MPa and 22.90 kN·m, respectively, while the average ratio between the split tensile and compressive strengths is around 0.09. Therefore, the fly ash-based geopolymer concrete can be used in structural components.

Strength characteristics of fibre reinforced self compacting concrete using marble sludge powder

The increasing demand for sustainable building materials has spurred interest in using natural fibers for construction. This study evaluates the performance of henequen and sisal fibers in mortar to enhance their tensile properties and provide alternatives to synthetic fibers. Mortar samples were prepared using a 1:3 mix ratio, with fibers introduced at 0%, 0.5%, 1%, 1.5%, and 2% by weight. The particle size distribution, setting times, consistency, and water ab-sorption and tensile strength of mortar constituents and fibers were determined. Compressive and splitting tensile strength tests were conducted on samples of 75 mm cubes and 50 × 100 mm cylinders at 7, 14, 21, and 28 days, respectively. Data were analyzed using ANOVA at α = 0.05 and a validated Artificial Neural Network (ANN) model. Henequen fiber exhibited lower water absorption and higher tensile strength. The 1% mixture recorded the highest com-pressive strength of 15.08 MPa and 15.41 MPa, and the split tensile strength at 0.5% mixture was 3.43 MPa and 3.51 MPa at 28 days, respectively. ANOVA confirmed significant dif-ferences in tensile strength due to fiber inclusion, and compressive strength results indicated no statistically significant differences across samples. The ANN demonstrated high predic-tive accuracy, with R² values of 0.8785 and 0.7885, and low mean squared errors of 0.3855 and 0.4855, for compressive and split tensile strengths, supporting its use in performance forecasting. The optimum compressive strength was observed at a 1% fiber content, while the split tensile strength improved up to 0.5%. The experimental results support its application in sustainable construction.

Geopolymer concrete (GPC) serves as a sustainable substitute for conventional concrete by employing alternative cementitious materials such as fly ash (FA) instead of ordinary Portland cement (OPC), contributing to environmental and durability benefits. To increase the rate of utilization of FA in the construction industry, distinctive characteristics of two machine learning (ML) methods, namely, gene expression programming (GEP) and multi-expression programming (MEP), were utilized in this study to propose precise prediction models for the compressive strength and split tensile strength of GPC comprising FA as a binder. A comprehensive database was collated, which comprised 301 compressive strength and 96 split tensile strength results. Seven distinct input variables were employed for the modeling purpose, i.e., FA, sodium hydroxide, sodium silicate, water, superplasticizer, and fine and coarse aggregates contents. The performance of the developed models was assessed via numerous statistical metrics and absolute error plots. In addition, a parametric analysis of the finalized models was performed to validate the prediction ability and accuracy of the finalized models. The GEP-based prediction models exhibited better performance, accuracy, and generalization capability compared with the MEP-based models in this study. The GEP-based models demonstrated higher correlation coefficients (R) for predicting the compressive and split tensile strengths, with the values of 0.89 and 0.87, respectively, compared with the MEP-based models, which yielded the R values of 0.76 and 0.73, respectively. The mean absolute errors for the GEP- and MEP-based models for predicting the compressive strength were 5.09 MPa and 6.78 MPa, respectively, while those for the split tensile strengths were 0.42 MPa and 0.51 MPa, respectively. The finalized models offered simple mathematical formulations using the GEP and Python code-based formulations from MEP for predicting the compressive and tensile strengths of GPC. The developed models indicated practical application potential in optimizing geopolymer mix designs. This research work contributes to the ongoing efforts in advancing ML applications in the construction industry, highlighting the importance of sustainable materials for the future.

In this study, the effectiveness of waste Polyethylene Terephthalate (PET) fibers in improving the properties of concrete was investigated. Recycling of waste PET bottles is a daunting task in developing countries due to inadequate recycling facilities. The main aim of this research paper is to investigate the mechanical behavior of the components by using PET fibers. This paper describes the performance of PET fiber reinforced concrete for two grades of concrete mix M20 and M30. An experimental work has been carried out on the specimens like cubes, cylinders and beams which were casted in the laboratory and their behavior under the test was observed. The PET fibers were replaced to the fine aggregate volume from 0.0% to 2.0%. The compressive strength, split tensile strength and flexural strength of concrete were determined after 28 days of curing period. The highest compressive, split tensile and flexural strength of concrete was observed at 1.5% fiber volume replacement to the fine aggregate. The study concludes that the replacement of waste PET fibers to fine aggregate in concrete serves as a means of utilizing the waste generated by PET bottles to increase the strength of concrete.