Investigation of Cement-Emulsified Asphalt in Plastic Concrete

The mechanical, mesodamage, and the microproperties of cement-emulsified asphalt concrete have been investigated by computed tomography (CT), scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TG) in this work. Emulsified asphalt delayed the hydration of cement, making the early compressive strength of concrete develop slowly. However, the concrete compressive strength increased rapidly with the demulsification of emulsified asphalt. The damage stages of condense, expansion of volume, rapid crack propagation, and damage by real-time scanning have been observed. The CT mean value of the place near the lower end face suffered a larger decline but a smaller decline to the upper part of the sample. The evolution of concrete suffering damage to failure is a gradual development process, and no sharp expansion of brittle failure. The unhydrated cement, incorporation asphalt, fibrous C–S–H gel, CH, needle-shaped ettringite, and other hydration products were interwoven to constitute emulsified asphalt-cement paste, forming a spatial structure.

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Effect of Functional Superplasticizers on Concrete Strength and Pore Structure

Applied Sciences ◽

10.3390/app10103496 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3496

Author(s):

Wuju Xun ◽

Changlong Wu ◽

Xuefei Leng ◽

Jiye Li ◽

Desheng Xin ◽

...

Keyword(s):

Compressive Strength ◽

Pore Structure ◽

High Performance ◽

Concrete Strength ◽

Reducing Agents ◽

Reducing Agent ◽

Polycarboxylic Acid ◽

X Ray Diffraction ◽

Hydration Rate ◽

Compressive Strength Of Concrete

The current work investigates the fluidity and the loss of the flow rate of cement paste and mortar over time, as well as the pore structure and compressive strength of concrete and mortar in the presence of functional polycarboxylic acid high-performance water-reducing agents. The hydration rate, hydration products, and pore structure of the concrete containing different functional polycarboxylic acid superplasticizers were analyzed by means of mercury intrusion test, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The results show that water-reducing agent Z significantly improves the pore structure of concrete and further compacts the structure of concrete and mortar, thereby improving the compressive strength of concrete. Moreover, the shorter side chains and ester functional groups in the structure of water-reducing agent H can slow down cement hydration rate, which lowers the early strength of mortar; nevertheless, at later stages, the pore structure of the concrete and mortar including superplasticizer H is less different from that of the concrete and mortar containing polycarboxylic acid water-reducing agents. Water-reducing agent J performs best but has a weaker effect on the pore structure of concrete and mortar compared to superplasticizer Z; it is also better than naphthalene-based water-reducing agents.

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Research on the Mechanical Strength of Emulsified Asphalt-Cementstabilized Macadam Based on Neural Network Algorithm

The Open Civil Engineering Journal ◽

10.2174/1874149501509010929 ◽

2015 ◽

Vol 9 (1) ◽

pp. 929-933 ◽

Cited By ~ 1

Author(s):

Chenhao Guo ◽

Xianpeng Cheng ◽

Xiaoming Zhang

Keyword(s):

Neural Network ◽

Compressive Strength ◽

Mechanical Strength ◽

Experimental Result ◽

Rigid Base ◽

Research Approach ◽

Asphalt Cement ◽

Network Algorithm ◽

Neural Network Algorithm ◽

Emulsified Asphalt

In this paper, we researched the application of mechanical strength experiment on emulsified asphalt cementstabilized macadam based on neural network algorithm. Based on the analysis of the early diseases of asphalt pavement, which uses semi-rigid base, solving the problem of semi-rigid base asphalt pavement's reflection crack, this paper proposes the research approach that uses a modified semi-rigid base, appropriate pavement structure as the point of starting. Combining with the past emulsified asphalt-cement-stabilized macadam material mixing methods, the construction technologies of cement-stabilized macadam and synchronous chip sealing, this paper has come up with a new method for modification of semi-rigid base. The unconfined compressive strength and splitting strength of the mixtures would decrease as the mixing amount of emulsified asphalt increases, and the reduction rate of compressive strength decreases as the curing age grows. The mixing amount of emulsified asphalt has almost no influence on the flexural-tensile strength at normal temperature, so it can be ignored. The experimental result shows that the emulsified asphalt cement-stabilized macadam has good performance than traditional methods.

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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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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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