scholarly journals Transition Zone Enhancement with Waste Limestone Powder as a Reason for Concrete Compressive Strength Increase

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7254
Author(s):  
Maja Kępniak ◽  
Piotr Woyciechowski ◽  
Wojciech Franus
Keyword(s):  
Compressive Strength ◽  
Transition Zone ◽  
Limestone Powder ◽  
Partial Substitution ◽  
Strength Increase ◽  
Fine Aggregate ◽  
Ecological Aspects ◽  
Microscopic Evaluation ◽  
Strength Tests ◽  
Variable Water

Modification of concrete with waste materials is an increasingly common process, and they are primarily used as a partial substitution for cement. In the case of inert or nearly inert additions according to EN 206, the effectiveness of such a modification mainly concerns ecological aspects and, only to a small extent, mechanical properties. This article analyses the effect of modifying cement concrete with waste limestone powder as a partial substitution for fine aggregate. The analysed waste arises as a result of the accumulation of dust produced during the initial preparation of aggregate for the production of hot mix asphalt (HMA). In order to analyse the effect of waste on compressive strength, an experimental design was prepared with variable substitution levels and variable water/cement ratios. Compressive strength tests were performed after 28 to 90 days. Statistical analysis of the results was performed. Microscopic evaluation of the fractures of the samples was carried out to clarify the mechanism of transition zone enhancement, which resulted in an increase of compressive strength of the composite.

scholarly journals The influence of alkali-resistant glass fibres on properties of fine-aggregate concretes

2019 ◽  
Vol 262 ◽  
pp. 06003 ◽  
Author(s):  
Lucyna Domagała ◽  
Ewelina Bizoń-Żabińska ◽  
Kamil Kurzyniec
Keyword(s):  
Compressive Strength ◽  
Normal Weight ◽  
Strength Increase ◽  
Fine Aggregate ◽  
Natural Sand ◽  
Glass Fibres ◽  
Concrete Properties ◽  
Uniform Dispersion ◽  
Strength Tests ◽  
Glass Aggregate

The aim of this paper is to assess the effect of modification of fine-aggregate concrete properties with zirconia alkali-resistant glass fibres. Three types of fine-aggregate composites were subject to tests: normal-weight concretes made of natural sand, non-foamed and foamed lightweight concretes made of expanded glass aggregate. The concretes were modified with the glass fibres mainly in quantities ranged from 1.0 to 5.0 kg/m3. Even such low contents resulted in the increase of both flexural and compressive strength, by up to 45 % and 26 %, respectively. In the case of normal-weight fine-aggregate concretes the applied glass fibres turned out to be especially effective in improvement of the properties in early ages. At the age of 28 days both types of concretes revealed similar percentage strength increase. In comparison to HP 12 mm the application of longer fibres (HP 24 mm) led to slightly higher results of flexural strength tests. On the other hand, the shorter fibres were definitely more effective in the improvement of compressive strength due to their greater number and more uniform dispersion in concrete volume. The used contents of alkali-resistant glass fibres did affect neither density nor water absorption of the hardened concretes.

POTENTIAL USE COCONUT MILK AS ALTERNATIVE TO ALKALI SOLUTION FOR GEOPOLYMER PRODUCTION

2016 ◽  
Vol 78 (11) ◽  
Author(s):  
Gahasan Fahim Huseien ◽  
Jahangir Mirza ◽  
Mohd Warid Hussin ◽  
Mohd Azreen Mohd Ariffin
Keyword(s):  
Compressive Strength ◽  
Alkali Solution ◽  
Coconut Milk ◽  
Fine Aggregate ◽  
Strength Tests ◽  
Last Stage ◽  
The Cost ◽  
The Impact ◽  
Potential Use ◽  
Control Samples

This work aims to verify the feasibility of utilizing coconut milk as the alkali activator solution in geopolymer production and the impact on mortar properties; geopolymer mortar is  still more expensive than ordinary Portland cement mortar simply because the cost of alkali solution. Coconut milk is extensively available in Malaysia and very rich in potassium and sodium. In this research, the coconut milk was used as alkali solution (100%) at first, and then replaced by NaOH, Na2SiO3 and in the last stage mixed with NaOH and Na2SiO3 at 50%. Normal solution component of Na2SiO3 and NaOH with 8 M, and used as control samples. Binder to fine aggregate (B:A) and solution to binder (S:B) ratios were fixed at 1.5 and 0.30 respectively. Multi blend binder based geopolymer mortar are used in this study. The samples were cured with different conditions, cured at room temperature and oven temperature of 60 and 90°C. Compressive strength tests were carried out to determine the properties of hardened mortar. The samples prepared with coconut milk showed low compressive strength as compared to control samples, The results demonstrated that using coconut milk as alternative to alkali solution in geopolymer industry is not a viable option.

scholarly journals Effect on Strength Properties of Concrete Containing Seashell Powder as a Partial Substitution of Fine Aggregate and Silica Fume used as Admixture

2018 ◽  
Vol 7 (3.12) ◽  
pp. 689
Author(s):  
Pragadeesan S ◽  
Harishankar S
Keyword(s):  
Silica Fume ◽  
Strength Properties ◽  
Partial Substitution ◽  
Fine Aggregate ◽  
Split Tensile Strength ◽  
Conventional Concrete ◽  
Suitable Alternative ◽  
Pozzolanic Material ◽  
Strength Tests ◽  
The Cost

Sand is the most normally utilized fine aggregate in construction industry for the generation of concrete. The present scenario is in such a way that the cost of sand reached new heights and the demand for sand is also exhaustive. The replacement of the sand has a lot of constraints. Seashells are composed of calcium carbonate or chitin can be suitable alternative. It is used as a replacement of fine aggregate by 2%, 4%, 6%, 8%, and 10% for M20 grade concrete. Further 15% and 20% replacements are made. Silica fume is a ultrafine powder gathered as a result of silicon and ferrosilicon compound generation and the principle field of use is as pozzolanic material. It is used as an admixture by 5% to 10% of weight of cement to improve the strength properties. Concrete cubes and cylinders with mentioned proportion and conventional concrete are casted. Mechanical properties are evaluated by conducting compressive strength and split tensile strength tests.  

scholarly journals Modeling of Mechanical Properties of Silica Fume-Based Green Concrete Using Machine Learning Techniques

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 30
Author(s):  
Afnan Nafees ◽  
Muhammad Nasir Amin ◽  
Kaffayatullah Khan ◽  
Kashif Nazir ◽  
Mujahid Ali ◽  
...  
Keyword(s):  
Machine Learning ◽  
Mechanical Properties ◽  
Compressive Strength ◽  
Silica Fume ◽  
Sensitivity Analyses ◽  
Partial Substitution ◽  
Support Vector ◽  
Fine Aggregate ◽  
Statistical Parameters ◽  
Green Concrete

Silica fume (SF) is a frequently used mineral admixture in producing sustainable concrete in the construction sector. Incorporating SF as a partial substitution of cement in concrete has obvious advantages, including reduced CO2 emission, cost-effective concrete, enhanced durability, and mechanical properties. Due to ever-increasing environmental concerns, the development of predictive machine learning (ML) models requires time. Therefore, the present study focuses on developing modeling techniques in predicting the compressive strength of silica fume concrete. The employed techniques include decision tree (DT) and support vector machine (SVM). An extensive and reliable database of 283 compressive strengths was established from the available literature information. The six most influential factors, i.e., cement, fine aggregate, coarse aggregate, water, superplasticizer, and silica fume, were considered as significant input parameters. The evaluation of models was performed by different statistical parameters, such as mean absolute error (MAE), root mean squared error (RMSE), root mean squared log error (RMSLE), and coefficient of determination (R2). Individual and ensemble models of DT and SVM showed satisfactory results with high prediction accuracy. Statistical analyses indicated that DT models bested SVM for predicting compressive strength. Ensemble modeling showed an enhancement of 11 percent and 1.5 percent for DT and SVM compressive strength models, respectively, as depicted by statistical parameters. Moreover, sensitivity analyses showed that cement and water are the governing parameters in developing compressive strength. A cross-validation technique was used to avoid overfitting issues and confirm the generalized modeling output. ML algorithms are used to predict SFC compressive strength to promote the use of green concrete.

scholarly journals Optimizing Empty Fruit Bunch (EFB) of palm and glass powder as a partial substitution material of fine aggregate to increase compressive and tensile strength of normal concrete

2021 ◽  
Vol 878 (1) ◽  
pp. 012047
Author(s):  
R A Siregar ◽  
L E Hutabarat ◽  
S P Tampubolont ◽  
C C Purnomo
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Glass Powder ◽  
Fiber Material ◽  
Mix Design ◽  
Partial Substitution ◽  
Fine Aggregate ◽  
Empty Fruit Bunch ◽  
Normal Concrete ◽  
Compressive Strength Of Concrete

Abstract As a material of construction, concrete have a good compressive strength but low tensile strength. From the previous study, reducing the tensile weakness of the concrete using empty fruit bunch (EFB) of Palm for the concrete mix have a significant result. But in contrary, the use of this fiber decreases the compressive strength of concrete. This research aims to optimize a mixture of glass powders on EFB fiber as a solution to increase the compressive and tensile in strength of concrete as well. The fiber material requires pre condition treatment which is soaked in 10% NaOH for 6-10 hours, then is followed with drying for 24 hours and finally cutting into 4 cm pieces long. Using glass powder as mix design with fiber material which is substitute for fine aggregate in concrete. Variation of 0.25%, 0.5%, 0.75%, 1%, 1,25%, 1,5%, 1,75%, and 2% fiber material mix up with 10% glass powder used for concrete specimens with a diameter of 15 cm and a height of 30 cm at the age of 28 days testing. The results of this study shows an increase in the compressive and tensile strength of concrete compare to normal concrete. The optimum compressive increase 21.02% of normal concrete which is 24.87 MPa. Meanwhile the tensile strength an increase of 31,78% of normal concrete which is 3,11 MPa using 1% fibre and 10% of glass powder. Hence, using glass powder mix in EFB to increase compressive and tensile strength of concrete can be developed optimally in the future.

scholarly journals Studi Mengenai Perancangan Campuran Beton Abu Terbang dengan Pendekatan Blended Sand (Hal. 88-97)

2018 ◽  
Vol 4 (4) ◽  
pp. 88
Author(s):  
Reza Fauzi Nirwan ◽  
Priyanto Saelan
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Aggregate Size ◽  
Maximum Aggregate Size ◽  
Fine Aggregate ◽  
Concrete Compressive Strength ◽  
Fly Ash Concrete ◽  
Is Research ◽  
Strength Tests ◽  
Concrete Mix

ABSTRAKPenelitian ini dilakukan untuk mengetahui hasil perancangan campuran beton abu terbang yang mensubtitusi semen dengan cara pendekatan sand blended, yaitu abu terbang yang mensubtitusi semen diperlakukan sebagai agregat halus, sehingga agregat halus merupakan campuran dari pasir dan abu terbang. Penelitian dilakukan dengan kuat tekan rencana 20 MPa dan 30 MPa. Substitusi semen oleh abu terbang sebesar  10 %, 20 %, dan 30 % dari berat semen. Ukuran maksimum agregat kasar yang digunakan adalah 20 mm, dan pasir dengan modulus kehalusan 2,768, slump rencana 6 cm dan 10 cm. Hasil pengujian tekan silinder beton berdiameter 10 cm dan tinggi 20 cm menunjukkan bahwa kuat tekan beton abu terbang yang dihasilkan berdekatan dengan beton acuan yaitu beton tanpa abu terbang, untuk semua kadar abu terbang yaitu sampai dengan kadar subtitusi semen oleh abu terbang sebesar 30 %. Pendekatan sand blended dapat dilakukan dalam perancangan campuran beton abu terbang.Kata Kunci : beton abu terbang, kuat tekan, pasir blendedABSTRACTThis is research was performed to know the result of the test of fly ash concrete mix designed by sand blended method. Fly ash will be treated as fine aggregate so that the total fine aggregate is the consist of fly ash and sand. 20 MPa and 30 MPa concrete mix are designed for 10 %, 20 % and 30 % by weight of cement subtitution by fly ash. Concrete mix use 20 mm maximum aggregate size, finess modulus of sand 2.768, and 6 cm and  10 cm slump. Compressive strength tests of 10 cm diameter and 20 cm height cylinder showed that the stength of fly ash concrete is the same as the strength of initial concrete. Fly ash concrete mix can be designed by sand blended approximation.Keywords : fly ash concrete, compressive strength, blended sand

scholarly journals Behaviour of Light Weight Brick with the Influence of EPS Beads and Silica Fume

2020 ◽  
Vol 9 (3) ◽  
pp. 862-867
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Water Absorption ◽  
Silica Fume ◽  
Expanded Polystyrene ◽  
Partial Substitution ◽  
Fine Aggregate ◽  
Light Weight ◽  
Literature Study ◽  
Thermal Insulating

The principal reason behind this experimental investigation carried out here is to diminish the dead load of structures with the potential use of light weight bricks. EPS beads and silica fume are light in nature. The investigation work enhanced, with numerous literature study to find out the utilization of Expanded polystyrene(EPS) beads and silica fume in light weight brick can be used in military bases in cold regions due to its low thermal insulating quality. The main objective of this research is to prepare a light weight brick by partial substitution of Cement with silica fume and the replacement of fine aggregate with EPS beads. A total of 70 bricks containing two different sizes of EPS beads say Type A and Type B with different proportions (0%, 7%, 14%, 21%) of each Type were casted in order to check the mechanical properties such as compressive strength, water absorption, efflorescence, workability, and thermal conductivity of the brick. The compressive strength test was carried out at 7, 14 and 28 days of curing. As the percentage of EPS beads in the brick increased the strength of brick decreased while with the increase of EPS beads in the brick the water absorption as well as the thermal conductivity of brick decreased. There were slight presence of Efflorescence in some of the bricks while in most of the brick there were no efflorescence found.

scholarly journals Performance of self-compacting rubberized concrete

2018 ◽  
Vol 149 ◽  
pp. 01070 ◽  
Author(s):  
Bensaci Hamza ◽  
Menadi Belkacem ◽  
Kenai Said ◽  
Yahiaoui Walid
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Partial Substitution ◽  
Fine Aggregate ◽  
Rubberized Concrete ◽  
Rubber Waste ◽  
Waste Tyres ◽  
Hardened State ◽  
Hardened Properties ◽  
And Storage

Used tyre rubber wastes present a serious environmental problem of pollution and storage. The recycling of this waste in the industry of construction could be an appropriate solution to produce an eco-concrete and could contribute to the improvement of some of its properties. This paper aims to study the possibility of using tyre rubber waste as fine aggregate replacement in self-compacting concrete (SCC). Fines rubber particles of 0-2 mm of waste tyres were added SCC mixtures as a partial substitution of the total volume of sand at different percentages (5, 10, 15, 20 and 30%). The influence of fines rubber of used tyres on fresh and hardened properties of the SCC was investigated. The fresh properties of SCC were performed by using slump-flow, T50 flow time, L-box, V-funnel and segregation resistance tests. Characteristics of the hardened state were obtained by compressive strength and thermal conductivity. The experimental results showed that the inclusion of fines rubber in SCC decreases the workability, reduced its passing capacity and increases the possibility of blocking. A decrease in compressive strength is observed with the increase in rubber content. On the other hand, the incorporation of the rubber fines aggregates enhances in a remarkably way the thermal conductivity.

scholarly journals Utilization of Oyster Shells as a Substitute Part of Cement and Fine Aggregate in the Compressive Strength of Concrete

2020 ◽  
Vol 9 (3) ◽  
pp. 150-156
Author(s):  
Bunyamin Bunyamin ◽  
Amir Mukhlis
Keyword(s):  
Compressive Strength ◽  
Los Angeles ◽  
Oyster Shell ◽  
Partial Substitution ◽  
Test Machine ◽  
Fine Aggregate ◽  
Cement Replacement ◽  
Los Angeles Test ◽  
Concrete Production ◽  
Compressive Strength Of Concrete

The compressive strength of concrete depends on the physical characteristics of the concrete forming materials. Oyster shells originating from Krueng Neng, Aceh Besar are very abundant, left unattended by fishermen, causing pollution of the surrounding environment. Oyster shell dust contains CaO, which can be used as a partial substitution of cement. Therefore, it is necessary to study oyster shell ash as cement replacement and fine aggregate in concrete production. This research aims to determine the compressive strength of concrete using shell ash as cement replacement and fine aggregate. The oyster shells were obtained from Krueng Neng, Lamjamee Village, Jaya Baru, Aceh Besar District. The oyster shells were crushed with a Los Angeles Test machine and sieved with sieve size 2.36 mm for fine aggregate and sieve #200 for cement replacement. The water-cement ratios (w/c) were 0.4, 0.5 and 0.6. The results showed that concrete's compressive strength with 5% cement replacement level was higher than the concrete with cement only. Meanwhile, for other replacement levels, the compressive strengths of concrete specimens were lower than control specimens.  

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