scholarly journals Experimental Testing of the Effects of Fine Particles on the Properties of the Self-Compacting Lightweight Concrete

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Sandra Juradin ◽  
Goran Baloević ◽  
Alen Harapin

The self-compacting lightweight concrete (SCLC) is a combination of the Self compacting concrete (SCC) and the Lightweight concrete. It combines all the good properties of those two materials and is extremely convenient for the construction of buildings that require low mass and do not require high compressive strength, for example restoration works in old structures (e.g., replacement of wooden floors), prefabricated elements that require transportation, and for structures and elements where the concrete surface should be visible. In this paper the effect of the amount of fine particles on the properties of the self-compacting lightweight concrete (SCLC) in the fresh and hardened state was explored. For this purpose, sets of specimens with different combinations of admixtures of silica fume, fly ash, and filler were prepared and tested. Slump flow and flow time of fresh concrete, as well as the dynamic elastic modulus and compressive strength of hardened concrete, were measured at different ages of concrete. The processes of manufacturing and methods of testing are described, as well as the obtained results.

Author(s):  
A.O Adeyemi ◽  
M.A Anifowose ◽  
I.O Amototo ◽  
S.A Adebara ◽  
M.Y Olawuyi

This study examined the effect of varying water cement ratio on the compressive strength of concrete produced using palm kernel shell (PKS) as coarse aggregate at different replacement levels. The replacement levels of coarse aggregate with palm kernel shells (PKS) were 0%, 25%, 50%, and 100% respectively. PKS concrete cubes (144 specimens) of sizes 150mm x 150mm x 150mm were cast and cured in water for 7, 14, 21 and 28 days respectively. A mix ratio of 1:2:4 was adopted with water-cement ratio of 0.45, 0.5, and 0.6 respectively while the batching was done by weight. Slump test was conducted on fresh concrete while compressive strength test was carried out on the hardened concrete cubes using a compression testing machine of 2000kN capacity. The result of tests on fresh concrete shows that the slump height of 0.45 water cement ratio (w/c) increases with an increase in PKS%. This trend was similar to 0.50 and 0.60 w/c. However, the compressive strength of concrete cube decreases with an increase in w/c (from 0.45 to 0.60) but increases with respect to curing age and also decreases with increase in PKS%. Concrete with 0.45 water-cement ratio possess the highest compressive strength. It was observed that PKS is not a good substitute for coarse aggregate in mix ratio 1:2:4 for concrete productions. Hence, the study suggest the use of chemical admixture such as superplasticizer or calcium chloride in order to improve the strength of palm kernel shells-concrete.


2019 ◽  
Vol 9 (5) ◽  
pp. 4596-4599 ◽  
Author(s):  
N. Bheel ◽  
R. A. Abbasi ◽  
S. Sohu ◽  
S. A. Abbasi ◽  
A. W. Abro ◽  
...  

This study was undertaken to reduce the usage of cement in concrete where different proportions of tile powder as cement replacement were used. Since in the manufacture of cement an exuberant amount of carbon dioxide is disposed of in the environment, this research aims to curtail the dependence on cement and its production. The objective of this work is to investigate the properties of fresh mix concrete (workability) and hardened concrete (compressive and splitting tensile strength) in concrete with different proportions of 0%, 10%, 20%, 30%, and 40% of tile powder as a cement substitute. In this study, a total of 90 concrete samples were cast with mix proportions of 1:1.5:3, 0.5 water-cement ratio, cured for 7, 14 and 28 days. For determining the compressive strength, cubical samples, with dimensions of 100mm×100mm×100mm, were cast, while for the determination of the splitting tensile strength, cylindrical samples with dimensions of 200mm diameter and 100mm height, were tested after 7, 14, and 28 days. The highest compressive strength of concrete achieved for tile powder concrete was 7.50% at 10% replacement after 28days of curing. The splitting tensile strength got to 10.2% when concrete was replaced with 10% of tile powder and cured for 28 days. It was also shown that with increasing percentage of the tile powder content, the workability of the fresh concrete increases.


Author(s):  
Barkha Verma

Abstract: Aggregates provide volume at low cost, comprising 66% to 78% of the concrete. With increasing concern over the excessive exploitation of natural and quality aggregates, the aggregate produced from industrial wastes and agricultural wastes is the viable new source for building material. This study was carried out to determine the possibilities of using coconut shells as aggregate in concrete. Utilizing coconut shells as aggregate in concrete production not only solves the problem of disposing of this solid waste but also helps conserve natural resources. In this paper, the physical properties of crushed coconut shell aggregate were presented. The fresh concrete properties such as the density and slump and 28 days compressive strength of lightweight concrete made with coconut shell as coarse aggregate were also presented. The findings indicate that water absorption of the coconut shell aggregate was high about 24% but crushing value and impact value were comparable to that of other lightweight aggregates. The average fresh concrete density and 28days cube compressive strength of the concrete using coconut shell aggregate 1975kg/m3 and 19.1 N/mm2 respectively. It is concluded that crushed coconut shell is suitable when it is used as a substitute for conventional aggregates in lightweight concrete production. Keywords: Coarse Aggregate, Cement, Concrete, Fly Ash, Coconut shell Aggregate, Water, Compressive Strength, Workability, Fine Aggregate.


2018 ◽  
Vol 149 ◽  
pp. 01054
Author(s):  
Nadia Tebbal ◽  
Zine El Abidine Rahmouni ◽  
Lamis Rabiaa Chadi

The objective of this study is to analyze the effect of the air entrainment on the fresh rheological properties as well as on the compressive mechanical resistances of the mortars. The hardened concrete contains a certain amount of randomly spread air, coming either from a drive during kneading or from the evaporation of the mixing water. The air quantity is in the order of 20 l / m3, ie 2% of the volume. However, the presence of a large volume of air bubbles causes the mechanical resistances to fall in compression. On the other hand, the use of air entrainment could improve the rheological properties of fresh concrete. Experimental studies have been carried out to study the effect of air entrainment on compressive strength, density and ingredients of fresh concrete mix. During all the study, water cement ratio (w/c) was maintained constant at 0.5. The results have shown substantial decreasing in water and mortar density followed with decreasing in compressive strength of mortar. The results of this study has given more promising to use it as a guide for mortar mix design to choose the most appropriate concrete mix design economically.


2014 ◽  
Vol 629-630 ◽  
pp. 462-466
Author(s):  
Mei Yan Hang ◽  
Ying Jing Lan ◽  
Pei Yu Zhang ◽  
Li Ming Zhang

Abstract: The same amount of mixture ratio of cement, replacing a part of fly ash with a certain amount of mud to research about the workability of fresh concrete and the effect of the mechanical and shrinkage properties of hardened concrete. Test's results show: The different kinds of mud lead that the fluidity of the fresh concrete and the strength of hardened concrete are different. The influence of sand mud is lighter than planting mud on the fluidity and strength of concrete. The compressive strength of concrete decreases and the early shrinkage increase with an increase of mud replaced the fly ash.


2015 ◽  
Vol 1106 ◽  
pp. 17-20 ◽  
Author(s):  
Adam Hubáček ◽  
Tomáš Jarolím ◽  
Petra Macháňová

The paper deals with the topic of concrete for water-tight tunnel lining. This theme is currently very topical both in the Czech Republic and abroad. The focus is on requirements and properties of fresh concrete for manufacture of these specific concrete structures. Properties of hardened concrete will be examined, too: compressive strength, resistance to pressure water, durability and other parameters.


Author(s):  
Chidananda G

Abstract: This paper presents an experimental investigation on influence of different curing methods on the performance of M30 grade concrete. Different curing methods such as air curing, pond curing, intermittent curing, gunny bags curing, chemical curing and using Super Absorbent Polymer (SAP) by 0.3% of weight of cement are considered. Slump and compacting factor tests are performed to know the workability of fresh concrete. Compressive strength of hardened concrete is determined for concrete specimens cured by different curing methods. Durability in terms of carbonation resistance on hardened concrete is also performed as per IS 516 (Part 5/Sec 3, 2021) codal provisions. Depending upon the site conditions and availability of potable water, curing methods such as pond curing, intermittent curing, gunny bags curing, chemical curing and SAP curing can be adopted in site to achieve the expected strength and durability requirements. Keywords: Curing methods, Compressive strength and Carbonation resistance.


2021 ◽  
Vol 107 ◽  
pp. 113-121
Author(s):  
Akeem Ayinde Raheem ◽  
Bolanle Deborah Ikotun ◽  
S. Oyetunde Akinloye

Aggregates constitute 60 – 80% of total concrete constituents. The characteristics of concrete may be affected by the sources from which the aggregate was obtained. The effects of granite sourced from four selected locations within Ogbomoso, Nigeria; on the fresh and hardened properties of concrete were investigated. The granites were obtained from: Asafa (80 4.681 N and 40 20.781 E), Ola-jesu (80 13.591 N and 40 10.11 E), Igbo-ile (80 4.681 N and 40 19.571 E) and Apasu (80 14.961 N and 40 10.051 E). Sieve analysis, specific gravity, moisture content, Aggregate Crushing Value (ACV) and Aggregate Impact Value (AIV) of the granites were determined. The aggregates were used to produce concrete of two different mix ratio-1:2:4 and 1:3:6. Slump and compaction factor tests were carried out on fresh concrete and compressive strength, splitting tensile strength and water absorption on hardened concrete. The results indicated that granite obtained from Asafa and Ola-jesu exhibited improved characteristics over those sourced from Igbo-ile and Apasu and are more suitable for use in producing high-quality concrete.


2018 ◽  
Vol 272 ◽  
pp. 203-208
Author(s):  
Adam Hubáček

The paper focuses on the problems of concrete for water-tight concrete structure and with systém and regulations for design and application of these structures. The theme is currently quite topical in the Czech Republic and abroad. The accent is put particularly on the requirements and properties of fresh concrete or self-compacting concrete for manufacture of specific concrete structures. Properties of hardened concrete will be also observed; in particular compressive strength, resistance to pressure water, durability and other parameters.


2020 ◽  
Vol 157 ◽  
pp. 06022
Author(s):  
Liliya Kazanskaya ◽  
Olga Smirnova

There are several factors that affect the fresh concrete workability: water demand and composition of Portland cement, properties of fine and coarse aggregates, presence of superplasticizer and others admixtures, etc. Influence of quantity and fineness of ground quartz additives as well as polycarboxylate-based superplasticizer amount on workability of fresh concrete was studied in the paper. The properties of fresh mixture (slump) and hardened concrete (compressive strength at the age of 24 hours, 28 and 360 days) were estimated. Enhancing the fresh concrete workability using fine ground quartz sand was stated. Savings of superplasticizer per 1 m3 of slab concrete and 1 km of the ballastless track were calculated.


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