Influence of fly-ashes on properties of ordinary concretes

Abstract Influence of fly-ashes on properties of ordinary concretes. Care of the environment in accordance with the principles of sustainable development introduces the possibility and need for waste recycling. The construction and building materials industry has the greatest potential for reuse of waste. The article presents the results of investigations of selected properties (consistency, water absorbability, compressive strength and tensile strength after 28 and 56 days of curing, depth of penetration) of ordinary concretes and concretes containing fly-ashes - calcareous and siliceous ash − in their composition. To make the samples, the Portland cement CEM I 42.5 R and natural aggregate with graining of 0-16 mm were used. The concrete with siliceous and calcareous admixtures was made in three lots where the ash was added in the quantity of 15, 20 and 30% of the cement mass. After the tests, it was stated that the fly-ash admixture does not increase the air content in the mix, it increases the compressive strength in time and the siliceous ash improves the splitting tensile strength.

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Clay-Based Products Sustainable Development: Some Applications

Sustainability ◽

10.3390/su13031364 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1364

Author(s):

Michele La Noce ◽

Alessandro Lo Faro ◽

Gaetano Sciuto

Keyword(s):

Sustainable Development ◽

Tensile Strength ◽

Compressive Strength ◽

Elastic Modulus ◽

Basalt Fibers ◽

Future Studies ◽

Clay Bricks ◽

Brick Powder ◽

Alkaline Resistance ◽

Raw Earth

Clay has a low environmental impact and can develop into many different products. The research presents two different case studies. In the first, the clay is the binder of raw earth doughs in order to produce clay-bricks. We investigate the effects of natural fibrous reinforcements (rice straws and basalt fibers) in four different mixtures. From the comparison with a mix without reinforcements, it is possible to affirm that the 0.40% of basalt fibers reduce the shrinkage by about 25% and increase the compressive strength by about 30%. Future studies will focus on identifying the fibrous effects on tensile strength and elastic modulus, as well as the optimal percentage of fibers. In the second study, the clay, in form of brick powder (“cocciopesto”), gives high alkaline resistance and breathability performance, as well as rendering and color to the plaster. The latter does not have artificial additives. The plaster respects the cultural instance of the original building. The research underlines how the use of a local (and traditional) material such as clay can be a promoter of sustainability in the contemporary building sector. Future studies must investigate further possible uses of clay as well as a proper regulatory framework.

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Influence of the surface treatment of tire rubber residues added in mortars

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952008000200001 ◽

2008 ◽

Vol 1 (2) ◽

pp. 113-120 ◽

Cited By ~ 11

Author(s):

A. C. Marques ◽

J. L. Akasaki ◽

A. P. M. Trigo ◽

M. L. Marques

Keyword(s):

Mechanical Properties ◽

Aqueous Solution ◽

Tensile Strength ◽

Compressive Strength ◽

Surface Treatment ◽

Water Absorption ◽

Modulus Of Elasticity ◽

Tire Rubber ◽

Flow Test ◽

Made In

In this work it was evaluated the influence tire rubber addition in mortars in order to replace part of the sand (12% by volume). It was also intended to verify if the tire rubber treatment with NaOH saturated aqueous solution causes interference on the mechanical properties of the mixture. Compressive strength, splitting tensile strength, water absorption, modulus of elasticity, and flow test were made in specimens of 5cmx10cm and the tests were carried out to 7, 28, 56, 90, and 180 days. The results show reduction on mechanical properties values after addition of tire rubber and decrease of the workability. It was also observed that the tire rubber treatment does not cause any alteration on the results compared to the rubber without treatment.

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Study of the Effect of PP and LDPE Thermoplastic Binder Addition on the Mechanical Properties and Physical Properties of Particulate Composites for Building Material Application

Materials Science Forum ◽

10.4028/www.scientific.net/msf.964.115 ◽

2019 ◽

Vol 964 ◽

pp. 115-123

Author(s):

Sigit Tri Wicaksono ◽

Hosta Ardhyananta ◽

Amaliya Rasyida ◽

Feisha Fadila Rifki

Keyword(s):

Mechanical Properties ◽

Compression Strength ◽

Building Materials ◽

Construction Material ◽

Construction Materials ◽

Physical And Mechanical Properties ◽

Waste Recycling ◽

Plastic Waste ◽

Particulate Composites ◽

Water Absorbability

Plastic waste is majority an organic material that cannot easily decomposed by bacteria, so it needs to be recycled. One of the utilization of plastic waste recycling is become a mixture in the manufacture of building materials such as concrete, paving block, tiles, roof. This experiment purpose to find out the effect of addition of variation of LDPE and PP thermoplastic binder to physical and mechanical properties of LDPE/PP/Sand composite for construction material application. In this experiment are using many tests, such are SEM, FTIR, compression strength, density, water absorbability, and hardness. the result after the test are the best composition of composite PP/LDPE/sand is 70/0/30 because its have compression strength 14,2 MPa, while density value was 1.30 g/cm3, for the water absorbability is 0.073%, and for the highest hardness is 62.3 hardness of shore D. From the results obtained, composite material can be classified into construction materials for mortar application S type with average compression strength is 12.4 MPa.

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Fly Ash-Based Geopolymer Building Materials for Green and Sustainable Development

Materials ◽

10.3390/ma13245699 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5699

Author(s):

Rosicky Methode Kalombe ◽

Victor Tunde Ojumu ◽

Chuks Paul Eze ◽

Sammy Mwasaha Nyale ◽

John Kevern ◽

...

Keyword(s):

Sustainable Development ◽

Compressive Strength ◽

Fly Ash ◽

Environmental Impact ◽

Co2 Emissions ◽

Building Materials ◽

Curing Conditions ◽

High Alkalinity ◽

Series Of Experiments ◽

Minimal Environmental Impact

This study reports on formulations and conditions for producing fly ash-based geopolymers with a view to showing that the compressive strength required for construction applications can be obtained without the addition of aggregates, sand, and/or cement. It was shown in a series of experiments constituting at least 73% fly ash that a compressive strength of up to 90 MPa can be obtained depending on the curing conditions. While high alkalinity resulted in stronger materials, the results showed about 40% savings in CO2 emissions without using sand and cement. Such materials are suited for construction applications with minimal environmental impact.

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Experimental Study on Mechanical Properties and Fractal Dimension of Pore Structure of Basalt–Polypropylene Fiber-Reinforced Concrete

Applied Sciences ◽

10.3390/app9081602 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1602 ◽

Cited By ~ 8

Author(s):

Ditao Niu ◽

Daguan Huang ◽

Hao Zheng ◽

Li Su ◽

Qiang Fu ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Fractal Dimension ◽

Pore Structure ◽

Polypropylene Fiber ◽

Splitting Tensile Strength ◽

Fiber Reinforced Concrete ◽

Hybrid Fibers ◽

Air Content

This study investigates the effects of basalt–polypropylene fibers on the compressive strength and splitting tensile strength of concrete and calculates the fractal dimension of the pore structure of concrete by using a fractal model based on the optical method. Test results reveal that hybrid fibers can improve the compressive strength and splitting tensile strength of concrete, and the synergistic effect of the hybrid fibers is strongest when the contents of basalt fiber (BF) and polypropylene fiber (PF) are 0.05% each, and that the maximum increments in compressive strength and splitting tensile strength are 5.06% and 9.56%, respectively. The effect of hybrid fibers on splitting tensile strength is greater than on compressive strength. However, hybrid fibers have adverse effects on mechanical properties when the fiber content is too high. The pore structure of basalt–polypropylene fiber-reinforced concrete (BPFRC) exhibits obvious fractal characteristics, and the fractal dimension is calculated to be in the range of 2.297–2.482. The fractal dimension has a strong correlation with the air content and spacing factor: the air content decreases significantly whereas the spacing factor increases with increasing fractal dimension. In addition, the fractal dimension also has a strong positive correlation with compressive strength and splitting tensile strength. Therefore, the fractal dimension of the pore structure can be used to evaluate the microscopic pore structure of concrete and can also reflect the influence of the complexity of the pore structure on the macroscopic mechanical properties of concrete.

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Variability Assessment of the Compressive and Tensile Strength of Fibred Earthen Composites

10.4028/www.scientific.net/cta.1.612 ◽

2022 ◽

Author(s):

Philippe Poullain ◽

Mircea Barnaure ◽

Stéphanie Bonnet

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Standard Deviation ◽

Probability Density Function ◽

Building Materials ◽

Mean Value ◽

Rammed Earth ◽

The Mean ◽

The Many

Earthen composites (rammed earth, cob, adobe, daub, CEB...) are experiencing renewed interest from builders due to the many advantages of these building materials, and in particular their eco-friendliness. Nevertheless, the widespreading of these materials, as certified materials and conforming to construction standards, comes against the lack of data concerning their mechanical properties. Indeed, the literature generally gives the average values of the properties without indicating the number of specimens tested neither the distribution of the data. Yet, the mean value of the compressive strength is not enough to assess the reliability of a given earthen composite to build a wall and it would be better to indicate the value of a defined percentile (characteristic value just like with concrete composites). The aim of this paper is to analyze the data about the mechanical properties (tensile and compressive strength) obtained on different formulations of cob including natural fibres or not. The tests performed allowed to determine the probability density function and the average values, the standard deviation and the percentiles, for the various properties.

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A Study on Mechanical Properties of Conventional Concrete and Coconut Shell Concrete by Replacing Cement with Silica Fume

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.12.11512 ◽

2018 ◽

Vol 7 (2.12) ◽

pp. 437

Author(s):

V R.Prasath Kumar ◽

K Gunasekaran ◽

Sreerag K P

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Flexural Strength ◽

Silica Fume ◽

Building Materials ◽

Coarse Aggregate ◽

Coconut Shell ◽

Split Tensile Strength ◽

Conventional Concrete ◽

Coconut Shells

High standing estimation of building materials utilized for development is a component of incredible concern. Coconut shell as a completely substitution in the place of coarse aggregate may totally effective for designers in construction industry. The coconut shell concrete is a light weight solid which may decrease the self-heap of a structure. The under taken project depends on inspecting attributes of coconut shell concrete when contrasted with conventional concrete. Coconut shells going from 10mm strainer and held on 6.3mm were considered to utilize for this study. For the current study M100 grade concrete is used to cast the specimens. The principle properties considered testing on coconut shell concrete and conventional concrete is compressive strength, split tensile strength and flexural strength. Examples were taken by supplanting coarse aggregate with coconut shells completely and cement is supplanted by silica fume with various extents of 5%, 10%, 15%, 20%, 25% for compressive strength test and tests were done at 3, 7, 28, 56 and 90 days of curing, it is observed that the ideal compressive strength outcomes were obtained at 10% of silica fume. The flexural strength and split tensile strength of the specimens are calculated with replacement of cement by silica fume with different extents of 0%, 5%, 10% and 15%, tests were done at 3, 7 and 28 days of curing. The optimum replacement percentage of cement by silica fume is 10% for compressive strength, split tensile and flexural strength. The primary principle is to lessen the utilization of natural aggregate by supplanting them with coconut shells and to decrease the density of concrete which makes concrete for simple dealing.

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Temperature Influence on Ordinary Concrete Modified with Fly Ashes from Thermally Conversed Municipal Sewage Sludge Strength Parameters

Materials ◽

10.3390/ma13225259 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5259

Author(s):

Gabriela Rutkowska ◽

Paweł Ogrodnik ◽

Joanna Fronczyk ◽

Ayla Bilgin

Keyword(s):

Compressive Strength ◽

Sewage Sludge ◽

Chemical Properties ◽

Waste Recycling ◽

Operating Conditions ◽

Municipal Sewage ◽

Municipal Sewage Sludge ◽

Fly Ashes ◽

Strength Parameters ◽

Physical And Chemical

Concrete is the most commonly used structural material, without which modern construction could not function. It is a material with a high potential to adapt to specific operating conditions. The use of this potential is made by its material modification. The aim of the performed investigations was the assessment of rational application possibilities of fly ashes from thermally conversed municipal sewage sludge as an alternative concrete admixture. A concrete mix was designed, based on the Portland cement CEM I 42.5R and containing various quantity of ash, amounting to 0–25% of cement mass. The samples were conditioned and heated in a furnace at the temperature of 300 °C, 500 °C, and 700 °C. Physical and chemical properties of the ashes as well as utility properties of the concrete, i.e., density, compressive strength after 28, 56, and 90 days of maturation, frost resistance, and compressive strength in high temperature were determined. The tests were performed at cubic samples with 10 cm edge. The replacement of a determined cement quantity by the fly ashes enables obtaining a concrete composite having good strength parameters. The concrete modified by the fly ashes constituting 20% of the cement mass achieved its average compressive strength after 28 days of maturation equal to 50.12 MPa, after 56 days 50.61 MPa and after 90 days 50.80 MPa. The temperature growth weakens the composite structure. The obtained results confirm the possibility of waste recycling in the form of fly ashes as a cement substitute in concrete manufacturing.

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The Use of Geopolymers for the Disposal of Asbestos-containing Materials

MATEC Web of Conferences ◽

10.1051/matecconf/202032201014 ◽

2020 ◽

Vol 322 ◽

pp. 01014

Author(s):

Michał Łach ◽

Katarzyna Lichocka ◽

Maria Hebdowska-Krupa ◽

Wei-Ting Lin ◽

Kinga Korniejenko

Keyword(s):

Compressive Strength ◽

Literature Review ◽

Appropriate Technology ◽

Cement Composites ◽

Fly Ashes ◽

Asbestos Fibers ◽

Geopolymer Matrix ◽

Asbestos Cement ◽

Strength Tests ◽

Made In

Asbestos is widely known as a hazardous material and can contribute to many diseases. Its removal and neutralization are complicated, it requires proper preparation and the use of appropriate technology. Immobilization of asbestos materials in geopolymers seems to be one of the alternatives to its storage in landfills. However, this requires several studies confirming the possibility of asbestos immobilization in geopolymers. Also, asbestos dust contains silicon and aluminum, which may prove useful in the production of geopolymers. The paper presents research results regarding the possibility of using geopolymers based on fly ashes for neutralizing asbestos. An up-to-date literature review on the technology of managing asbestos-containing products is presented. As a result of the research, partial usefulness of geopolymerization technology for binding and neutralizing waste with asbestos was found. The research was carried out using waste asbestos-cement composites. Mixtures based on geopolymers were made in which ground asbestos material was introduced in an amount of 30, 50 and 70% by weight. Compressive strength tests have shown that geopolymers with the addition of asbestos have compressive strength: over 34 MPa for a composition containing 30% of asbestos material and about 14 MPa for a composition containing 70% of asbestos material. SEM observations have shown that asbestos fibers do not dissolve in the geopolymer production process and they can still be a threat if the geopolymer matrix is damaged.

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Effect of Wollastonite Mineral on Fresh and Mechanical Properties of Concrete

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38447 ◽

2021 ◽

Vol 9 (10) ◽

pp. 496-500

Author(s):

Aman Sharma

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Silica Sand ◽

Concrete Technology ◽

Split Tensile Strength ◽

Durability Properties ◽

Good Improvement ◽

Strength And Durability ◽

Made In

Abstract: The wollastonite mineral are the main source of solid-state reaction from limestone and silica sand. Wollastonite is used as replacement of both sand and cement depending on size of wollastonite. Present study will provide better understanding of mechanical and durability properties of concrete in which cement is partially replaced with wollastonite. The present paper would contribute to the efforts being made in the field of concrete technology towards development of concretes possessing good strength and durability properties along with economic and ecological advantage. Based on the study, valuable advice will be given for concrete structures. It was found that with increase in amount of wollastonite, in concrete with workability of concrete decreases. It was also found that initial day’s strength is less for wollastonite concrete compare to control mix, but as the age increases they show good improvement in strength due to pozzalanic reaction. Optimum dosage is observed to be 15% WP which shows more strength compared to control mix. Keywords: wollastonite mineral, workability, compressive strength, split tensile strength.

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