Discussion: Cube tests and the uniaxial compressive strength of concrete

To explore the mechanical properties of concrete under true triaxial static compressive load after sulfate attack, uniaxial static compression test and true triaxial static compression test at four stress ratios were carried out on concrete specimens immersed in 15% sulfate solution for 0–120 days by the integrated true triaxial static and dynamic load testing system, and the variation of performance indicators such as the strength and deformation of concrete under the coupling action of sulfate attack and complex stress state was analyzed. The results show that the uniaxial compressive strength of concrete increases at the beginning and then decreases with the increase of sulfate attack time and reaches the peak on the 30th day, with an increase rate of 16.57%; the strength of concrete under triaxial compression increases significantly, and the maximum triaxial compressive strength is 3.18 times of uniaxial compressive strength under the combination of 0-day sulfate attack and 0.2 : 0.8 stress ratio; and the deterioration of concrete under sulfate attack is more prominent at high confining pressure, and as the sulfate attack worsens, the sensitivity of triaxial compressive strength of concrete to lateral compressive stress is reduced. In conclusion, triaxial compression can significantly enhance the ductility of concrete by playing a role in restraining the deformation and cracking of concrete after sulfate attack.

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Analyzing Uniaxial Compressive Strength of Concrete Using a Novel Satin Bowerbird Optimizer

10.31219/osf.io/5qmt7 ◽

2021 ◽

Author(s):

Hossein Moayedi ◽

Amir Mosavi

Keyword(s):

Compressive Strength ◽

Uniaxial Compressive Strength ◽

Search Algorithm ◽

Large Dataset ◽

Satin Bowerbird ◽

Proposed Model ◽

Compressive Strength Of Concrete ◽

Artificial Neural Network Ann ◽

Non Destructive ◽

New Algorithms

Surmounting the complexities in analyzing the mechanical parameters of concrete entails selecting an appropriate methodology. This study integrates artificial neural network (ANN) with a novel metaheuristic technique, namely satin bowerbird optimizer (SBO) for predicting uniaxial compressive strength (UCS) of concrete. For this purpose, the created hybrid is trained and tested using a relatively large dataset collected from the published literature. Three other new algorithms, namely Henry gas solubility optimization (HGSO), sunflower optimization (SFO), and vortex search algorithm (VSA) are also used as benchmarks. After attaining a proper population size for all algorithms, the Utilizing various accuracy indicators, it was shown that the proposed ANN-SBO not only can excellently analyze the UCS behavior, but also outperforms all three benchmark hybrids (i.e., ANN-HGSO, ANN-SFO, and ANN-VSA). In the prediction phase, the correlation indices of 0.87394, 0.87936, 0.95329, and 0.95663, as well as mean absolute percentage errors of 15.9719, 15.3845, 9.4970, and 8.0629%, calculated for the ANN-HGSO, ANN-SFO, ANN-VSA, and ANN-SBO, respectively, manifested the best prediction performance for the proposed model. Also, the ANN-VSA achieved reliable results as well. In short, the ANN-SBO can be used by engineers as an efficient non-destructive method for predicting the UCS of concrete.

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Variasi Penambahan Sika Cim Dan Fiber Kawat Pada Beton Mutu Fc’ 30 Mpa

Jurnal Intake : Jurnal Penelitian Ilmu Teknik dan Terapan ◽

10.32492/jintake.v9i2.776 ◽

2018 ◽

Vol 9 (2) ◽

pp. 67-73

Author(s):

M Zainul Arifin

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Curing Temperature ◽

Test Results ◽

Concrete Compressive Strength ◽

Normal Concrete ◽

Astm Method ◽

Additive Type ◽

Composition Variation ◽

Compressive Strength Of Concrete

This research was conducted to determine the value of the highest compressive strength from the ratio of normal concrete to normal concrete plus additive types of Sika Cim with a composition variation of 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1 , 50% and 1.75% of the weight of cement besides that in this study also aims to find the highest tensile strength from the ratio of normal concrete to normal concrete in the mixture of sika cim composition at the highest compressive strength above and after that added fiber wire with a size diameter of 1 mm in length 100 mm with a ratio of 1% of material weight. The concrete mix plan was calculated using the ASTM method, the matrial composition of the normal concrete mixture as follows, 314 kg / m3 cement, 789 kg / m3 sand, 1125 kg / m3 gravel and 189 liters / m3 of water at 10 cm slump, then normal concrete added variations of the composition of sika cim 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1.5%, 1.75% by weight of cement and fiber, the tests carried out were compressive strength of concrete and tensile strength of concrete, normal maintenance is soaked in fresh water for 28 days at 30oC. From the test results it was found that the normal concrete compressive strength at the age of 28 days was fc1 30 Mpa, the variation in the addition of the sika cim additive type mineral was achieved in composition 0.75% of the cement weight of fc1 40.2 Mpa 30C. Besides that the tensile strength test results were 28 days old with the addition of 1% fiber wire mineral to the weight of the material at a curing temperature of 30oC of 7.5%.

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Determination of Concrete Cube Strength from Used Samples / Určení Krychelné Pevnosti Betonu U Použitých Zkušebních Trámců

Transactions of the VŠB - Technical University of Ostrava Civil Engineering Series ◽

10.2478/v10160-012-0033-3 ◽

2012 ◽

Vol 12 (2) ◽

pp. 186-194 ◽

Cited By ~ 2

Author(s):

Oldřich Sucharda ◽

David Mikolášek ◽

Jiří Brožovský

Keyword(s):

Compressive Strength ◽

Concrete Beams ◽

Linear Analysis ◽

Bending Tests ◽

Cube Strength ◽

Non Linear ◽

Compressive Strength Of Concrete ◽

Concrete Cube

Abstract This paper deals with the determination of compressive strength of concrete. Cubes, cylinders and re-used test beams were tested. The concrete beams were first subjected to three-point or fourpoint bending tests and then used for determination of the compressive strength of concrete. Some concrete beams were reinforced, while others had no reinforcement. Accuracy of the experiments and calculations was verified in a non-linear analysis.

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Studies on Uniaxial Compressive Strength, Uniaxial Tensile Strength, Youngs Modulus, Poissons Ratio of Iron Ore in relation their Influence in Optimum Rock Blasting Process.Central Afghanistan

International Journal of Computer Sciences and Engineering ◽

10.26438/ijcse/v7i4.140151 ◽

2019 ◽

Vol 7 (4) ◽

pp. 140-151

Author(s):

Fatima Rezaye ◽

Shivanna .

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Uniaxial Compressive Strength ◽

Iron Ore ◽

Uniaxial Tensile ◽

Rock Blasting ◽

Uniaxial Tensile Strength ◽

Poissons Ratio

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Experimental Analysis of the Mechanical Properties and Resistivity of Tectonic Coal Samples with Different Particle Sizes

Energies ◽

10.3390/en14082303 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2303

Author(s):

Congyu Zhong ◽

Liwen Cao ◽

Jishi Geng ◽

Zhihao Jiang ◽

Shuai Zhang

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Compressive Strength ◽

Elastic Modulus ◽

Uniaxial Compressive Strength ◽

Coalbed Methane ◽

Coal Sample ◽

Fine Particles ◽

Particle Sizes ◽

Tectonic Coal

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.

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Towards Sustainable Concrete Composites through Waste Valorisation of Plastic Food Trays as Low-Cost Fibrous Materials

Sustainability ◽

10.3390/su13042073 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2073 ◽

Cited By ~ 1

Author(s):

Hossein Mohammadhosseini ◽

Rayed Alyousef ◽

Mahmood Md. Tahir

Keyword(s):

Compressive Strength ◽

Low Cost ◽

Impact Resistance ◽

Food Tray ◽

World Population ◽

Fibrous Materials ◽

Palm Oil Fuel Ash ◽

Waste Plastic ◽

Compressive Strength Of Concrete ◽

The Impact

Recycling of waste plastics is an essential phase towards cleaner production and circular economy. Plastics in different forms, which are non-biodegradable polymers, have become an indispensable ingredient of human life. The rapid growth of the world population has led to increased demand for commodity plastics such as food packaging. Therefore, to avert environment pollution with plastic wastes, sufficient management to recycle this waste is vital. In this study, experimental investigations and statistical analysis were conducted to assess the feasibility of polypropylene type of waste plastic food tray (WPFT) as fibrous materials on the mechanical and impact resistance of concrete composites. The WPFT fibres with a length of 20 mm were used at dosages of 0–1% in two groups of concrete with 100% ordinary Portland cement (OPC) and 30% palm oil fuel ash (POFA) as partial cement replacement. The results revealed that WPFT fibres had an adverse effect on the workability and compressive strength of concrete mixes. Despite a slight reduction in compressive strength of concrete mixtures, tensile and flexural strengths significantly enhanced up to 25% with the addition of WPFT fibres. The impact resistance and energy absorption values of concrete specimens reinforced with 1% WPFT fibres were found to be about 7.5 times higher than those of plain concrete mix. The utilisation of waste plastic food trays in the production of concrete makes it low-cost and aids in decreasing waste discarding harms. The development of new construction materials using WPFT is significant to the environment and construction industry.

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