scholarly journals Predicting the Mechanical Properties of Concrete Using Intelligent Techniques to Reduce CO2 Emissions

2019 ◽  
Vol 69 (334) ◽  
pp. 190 ◽  
Author(s):  
H. H. Ghayeb ◽  
H. A. Razak ◽  
N.H. R. Sulong ◽  
A. N. Hanoon ◽  
F. Abutaha ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Co2 Emissions ◽  
Coarse Aggregate ◽  
Experimental Results ◽  
Engineering Properties ◽  
Type I ◽  
Fine Aggregate ◽  
River Sand ◽  
Chemical Admixtures ◽  
Concrete Production

The contribution to global CO2 emissions from concrete production is increasing. In this paper, the effect of concrete mix constituents on the properties of concrete and CO2 emissions was investigated. The tested materials used 47 mixtures, consisting of ordinary Portland cement (OPC) type I, coarse aggregate, river sand and chemical admixtures. Response surface methodology (RSM) and particle swarm optimisation (PSO) algorithms were employed to evaluate the mix constituents at different levels simultaneously. Quadratic and line models were produced to fit the experimental results. Based on these models, the concrete mixture necessary to achieve optimum engineering properties was found using RSM and PSO. The resulting mixture required to obtain the desired mechanical properties for concrete was 1.10-2.00 fine aggregate/cement, 1.90-2.90 coarse aggregate/cement, 0.30-0.4 water/cement, and 0.01-0.013 chemical admixtures/cement. Both methods had over 94% accuracy, compared to the experimental results. Finally, by employing RSM and PSO methods, the number of experimental mixtures tested could be reduced, saving time and money, as well as decreasing CO2 emissions.

scholarly journals Suitability of Scoria as Fine Aggregate and Its Effect on the Properties of Concrete

2019 ◽  
Vol 11 (17) ◽  
pp. 4647 ◽  
Author(s):  
Warati ◽  
Darwish ◽  
Feyessa ◽  
Ghebrab
Keyword(s):  
Construction Materials ◽  
Energy Utilization ◽  
Engineering Properties ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Test Results ◽  
River Sand ◽  
Conventional Concrete ◽  
Efficient Energy ◽  
Concrete Production

The increase in the demand for concrete production for the development of infrastructures in developing countries like Ethiopia leads to the depletion of virgin aggregates and high cement demand, which imposes negative environmental impacts. In sustainable development, there is a need for construction materials to focus on the economy, efficient energy utilization, and environmental protections. One of the strategies in green concrete production is the use of locally available construction materials. Scoria is widely available around the central towns of Ethiopia, especially around the rift valley regions where huge construction activities are taking place. The aim of this paper is therefore to analyze the suitability of scoria as a fine aggregate for concrete production and its effect on the properties of concrete. A differing ratio of scoria was considered as a partial replacement of fine aggregate with river sand after analyzing its engineering properties, and its effect on the mechanical properties of concrete were examined. The test results on the engineering properties of scoria revealed that the material is suitable to be used as a fine aggregate in concrete production. The replacement of scoria with river sand also enhanced the mechanical strength of the concrete. Generally, the findings of the experimental study showed that scoria could replace river sand by up to 50% for conventional concrete production.

scholarly journals Mechanical properties of porous concrete with variations of coarse aggregate gradation

2019 ◽  
Vol 276 ◽  
pp. 01027
Author(s):  
Hazairin ◽  
Erma Desmaliana ◽  
Bernardinus Herbudiman ◽  
Wira Yudha Saputra
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Bending Strength ◽  
Coarse Aggregate ◽  
Experimental Results ◽  
Fine Aggregate ◽  
High Porosity ◽  
Aggregate Gradation ◽  
Porous Concrete ◽  
Air Content

Porous concrete is an innovation in sustainable concrete technology, which has high porosity concrete without fine aggregate. Porous concrete used in rain gardens, planter boxes, permeable pavements at urban open spaces could absorb rainwater so it can reduce run-off. This experimental study purposes to determine the compressive, split-tensile, flexural strengths, and permeability of porous concrete with various gradation of coarse aggregates. This study used a concrete mixture with coarse aggregate gradation variations of gap, continuous, and uniform on the water cement ratio of 0.4. The test specimens used three cylinders of 15x30cm for compressive and split-tensile strengths, except for uniform gradations used three cylinders of 10x20cm. Beam specimens of 15x15x60cm used for bending strength test by third point loading method. The tested mechanical properties are 7, 14, and 28 days-compressive strengths, 28 days split-tensile strength, and 28 days bending strength. The experimental results also show the average compressive strengths of porous concrete with variation of gradations of gap, continuous, and uniform for 28 days is 14.6 MPa, 13.0 MPa, and 10.6 MPa, respectively. Volumetric flow rate of porous concrete with gap, continuous, and uniform aggregate gradations is 28.4 ml/s, 32.1 ml/s, and 39.3 ml/s, respectively. The experimental results show that gap gradation is recommended due to its better compressive and flexural strengths. In porous concrete, aggregate gradations influence the air content. The highest air content results the lowest compressive strength of concrete. The designed air content should be controlled to maintain the expexted compressive strength of porous concrete.

scholarly journals Effect of Iron Slag and Robodust on the Mechanical Properties of Concrete

2020 ◽  
Vol 9 (6) ◽  
pp. 626-629
Keyword(s):  
Mechanical Properties ◽  
Carbon Dioxide ◽  
Building Materials ◽  
Coarse Aggregate ◽  
Carbon Dioxide Production ◽  
Waste Materials ◽  
Fine Aggregate ◽  
Conventional Concrete ◽  
Iron Slag ◽  
Concrete Production

Concrete is the composite material which is contains cement, coarse and fine aggregate. The real fact is that the concrete production was observed to be 10 billion tons per year, which is double the utilization of other building materials such as timber, steel, etc. Due to the efficient properties of concrete, it is broadly used in the construction of the buildings. To increase the mechanical properties of concrete and to make it more efficient, researcher have been conducting many experiments using various other materials as the substitute of cement, fine aggregate and coarse aggregate. Manufacturing of cement produces more carbon dioxide and thus in turn creates air pollution. In order to decrease carbon dioxide production, minimize the waste materials and to make the concrete eco-friendly and economical, robodust and iron slag has been adopted in this study. In this research, 30% robodust has been replaced with fine aggregate and 10%, 20%, 30%, 40% and 50% iron slag has been replaced with cement. The combination of robodust and iron slag replacement with fine aggregate and cement respectively has shown good increase in mechanical properties of concrete in contrast to conventional concrete.

scholarly journals Mix Design and Engineering Properties of Fiber-Reinforced Pervious Concrete Using Lightweight Aggregates

2022 ◽  
Vol 12 (1) ◽  
pp. 524
Author(s):  
Chao-Wei Tang ◽  
Chiu-Kuei Cheng ◽  
Lee-Woen Ean
Keyword(s):  
Mechanical Properties ◽  
Coarse Aggregate ◽  
Pervious Concrete ◽  
Mix Design ◽  
Engineering Properties ◽  
Fine Aggregate ◽  
Fiber Reinforced ◽  
Split Tensile Strength ◽  
Coarse Aggregates ◽  
The Matrix

The main purpose of this study was to investigate the mix design and performance of fiber-reinforced pervious concrete using lightweight coarse aggregates instead of ordinary coarse aggregates. There were two main stages in the relevant testing work. First, the properties of the matrix were tested with a rheological test and then different amounts of lightweight coarse aggregate and fine aggregate were added to the matrix to measure the properties of the obtained lightweight pervious concrete (LPC). In order to greatly reduce the experimental workload, the Taguchi experimental design method was adopted. An orthogonal array L9(34) was used, which was composed of four controllable three-level factors. There were four test parameters in this study, which were the lightweight coarse aggregate size, ordinary fine aggregate content, matrix type, and aggregate/binder ratio. The research results confirmed that the use of suitable materials and the optimal mix proportions were the key factors for improving the mechanical properties of the LPC. Due to the use of silica fume, ultrafine silica powder, and polypropylene fibers, the 28-day compressive strength, 28-day flexural strength, and 28-day split tensile strength of the LPC specimens prepared in this study were 4.80–7.78, 1.19–1.86, and 0.78–1.11 MPa, respectively. On the whole, the mechanical properties of the prepared LPC specimens were better than those of the LPC with general composition.

scholarly journals Mechanical Properties of Concrete with Substitution of Fine and Coarse Aggregate by Waste Materials in Concrete

2019 ◽  
Vol 8 (4) ◽  
pp. 5817-5820
Keyword(s):  
Mechanical Properties ◽  
Coarse Aggregate ◽  
Construction Materials ◽  
Copper Slag ◽  
Waste Materials ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
River Sand ◽  
Aggregate Concrete ◽  
Concrete Mixtures

Paper Construction industry has been conducted various studies on the utilization of waste materials in concrete productions in order to decrease the usage of natural resources. This research paper exhibits the evaluation and the effective reuse of waste construction materials and industries, such as cuddapah waste aggregate as partial replacement of conventional coarse aggregate and copper slag as partial replacement of river sand (fine aggregate). Experiments were conducted to find out the mechanical properties of concrete such as compressive, splitting tensile, flexural strengths and the modulus of elasticity of concrete for waste materials aggregate concrete and to compare them with those of conventional aggregate concrete. Results appear that waste materials in concrete have the potential to produce good quality concrete mixtures.

scholarly journals Comparison of Conventional Concrete and Replacement of River Sand by Waste Foundry Sand and Cement by Nano-Silica

2020 ◽  
pp. 201-205
Keyword(s):  
Experimental Investigation ◽  
Compressive Strength ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Nano Silica ◽  
River Sand ◽  
Conventional Concrete ◽  
Foundry Sand ◽  
Concrete Production ◽  
Waste Foundry Sand

This paper presents an experimental investigation on the properties of concrete in which like cement is partially replacing by used nano silica and is partially replacing by used waste foundry sand. Because now a day the world wide consumption of sand as cement and as fine aggregate in concrete production is very high. Nano silica and waste foundry sand are major by product of casting industry and create land pollution. The cement will be replaced with nano silica and the river sand will be replaced with waste foundry sand (0%, 5%, 10%, 15%, 20%). This experimental investigation was done and found out that with the increase in the nano silica and waste foundry sand ratio. Compression test has been done to find out the compressive strength of concrete at the age of 7, 14, 21, and 28. Test result indicates in increasing compressive strength of plain concrete by inclusion of nano silica as a partial replacement of cement and waste foundry sand as a partial replacement of fine aggregate.

scholarly journals Predicting the Mechanical Properties of RCA-Based Concrete Using Supervised Machine Learning Algorithms

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 647
Author(s):  
Meijun Shang ◽  
Hejun Li ◽  
Ayaz Ahmad ◽  
Waqas Ahmad ◽  
Krzysztof Adam Ostrowski ◽  
...  
Keyword(s):  
Machine Learning ◽  
Mechanical Properties ◽  
Mean Square Error ◽  
Coarse Aggregate ◽  
Machine Learning Algorithms ◽  
Supervised Machine Learning ◽  
Environmental Damage ◽  
Fine Aggregate ◽  
Mean Square ◽  
The Impact

Environment-friendly concrete is gaining popularity these days because it consumes less energy and causes less damage to the environment. Rapid increases in the population and demand for construction throughout the world lead to a significant deterioration or reduction in natural resources. Meanwhile, construction waste continues to grow at a high rate as older buildings are destroyed and demolished. As a result, the use of recycled materials may contribute to improving the quality of life and preventing environmental damage. Additionally, the application of recycled coarse aggregate (RCA) in concrete is essential for minimizing environmental issues. The compressive strength (CS) and splitting tensile strength (STS) of concrete containing RCA are predicted in this article using decision tree (DT) and AdaBoost machine learning (ML) techniques. A total of 344 data points with nine input variables (water, cement, fine aggregate, natural coarse aggregate, RCA, superplasticizers, water absorption of RCA and maximum size of RCA, density of RCA) were used to run the models. The data was validated using k-fold cross-validation and the coefficient correlation coefficient (R2), mean square error (MSE), mean absolute error (MAE), and root mean square error values (RMSE). However, the model’s performance was assessed using statistical checks. Additionally, sensitivity analysis was used to determine the impact of each variable on the forecasting of mechanical properties.

Experimental Study on Mechanical Properties of Fine Aggregate Concrete Made after Wet-Sieving Coarse Aggregate

2010 ◽  
Vol 168-170 ◽  
pp. 2200-2203 ◽  
Author(s):  
Shun Bo Zhao ◽  
Na Liang ◽  
Li Xin Liu ◽  
Li Sun ◽  
Su Yang
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Coarse Aggregate ◽  
Fine Aggregate ◽  
Concrete Wall ◽  
Aggregate Concrete ◽  
Structural Wall ◽  
Ordinary Concrete ◽  
Reinforced Composite ◽  
Wet Sieving

The validity of the wet-sieving concrete technique for building the reinforced composite concrete wall are demonstrated in the paper. The fine aggregate concrete made by ordinary concrete passing the sieve with square mash of 15 mm was cast for the surface layer, the recomposed concrete mixed by the residual concrete stayed on the sieve with the ordinary concrete was cast for the reinforced concrete structural wall. The mechanical properties such as the cubic and compressive strengths, the elastic modulus and the splitting and flexural tensile strengths of the fine aggregate concrete, the recomposed concrete and the ordinary concrete were tested and analyzed. The results show that the elastic modulus and splitting tensile strength of fine aggregate concrete reduce in some extent compared with that of ordinary concrete, the mechanical properties of recomposed concrete are almost the same as that of ordinary concrete.

scholarly journals Strength and Permeation Property of Concrete Made With Sugarcane Bagasse Ash and Granite Waste as Fine Aggregate Replacement

2019 ◽  
Vol 8 (3) ◽  
pp. 1982-1988
Keyword(s):  
Sugarcane Bagasse ◽  
Particle Packing ◽  
Industrial Wastes ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
River Sand ◽  
Conventional Concrete ◽  
Waste Concrete ◽  
Concrete Production ◽  
Sugarcane Bagasse Ash

Use of agro and industrial wastes in concrete production will cause sustainable concrete era and greener habitat. In this study an endeavor has been made to discover the propriety of Sugarcane Bagasse Ash (SCBA) and Granite Waste (GW) as partial replacement for traditional river sand. The percentage substitute is calculated based on the particle packing approach. The properties such as compressive, splitting tensile, flexural strengths and modulus of elasticity, water absorption, sorptivity and rapid chloride penetration test of the concrete with bagasse ash and granite waste as a partial replacement for river sand and to evaluate them with those of conventional concrete made with river sand fine aggregate are investigated. The test results show that the strength aspects of bagasse ash-granite waste concrete are higher than those of the conventional concrete. Moreover, they suggest that the bagasse ash-granite waste concrete has higher strength characteristics and remains in the lower permeability level shows improvement in overall durability of concrete than the conventional concrete.

scholarly journals Study on Mechanical Properties of PET Fiber-Reinforced Coal Gangue Fine Aggregate Concrete

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yanlin Huang ◽  
An Zhou
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Plain Concrete ◽  
Coal Gangue ◽  
Fine Aggregate ◽  
Replacement Rate ◽  
River Sand ◽  
Aggregate Concrete

In recent years, with the rapid development of the construction industry, the demand for natural river sand has become increasingly prominent. Development of alternatives to river sand has become an interesting direction for concrete research. In this paper, coal gangue was proposed to replace part of the river sand to produce coal gangue fine aggregate concrete, while waste polyethene terephthalate (PET) bottles were used as raw materials to make PET fibers to improve the mechanical properties of coal gangue fine aggregate concrete. There were two parts of the test conducted. In the first part, the compressive strength of the gangue fine aggregate concrete cube, splitting tensile strength, axial compressive strength, and static elastic modulus were studied when the substitution rate of coal gangue increased from 0% to 50%. Referring to the equation of the full stress-strain curve of plain concrete, the stress-strain constitutive equation of coal gangue fine aggregate concrete was analyzed and studied. By comparing with plain concrete, it was found that the coal gangue concrete with a replacement rate of 50% had higher compressive strength and tensile strength, but its brittleness was significantly greater than that of plain concrete in the later stage. In the second part, by studying the effect of different PET fiber content on the mechanical properties of coal gangue fine aggregate concrete with a replacement rate of 50%, it was found that when the addition of PET fiber was 0.1% and 0.3%, not only were compressive strength, splitting tensile strength, static elastic modulus, and flexural strength of the gangue fine aggregate concrete effectively improved but also the brittleness of concrete can be significantly reduced. The study found that after adding 0.3% PET fiber, the coal gangue fine aggregate concrete with a replacement rate of 50% has better mechanical properties and less brittleness.

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