scholarly journals Analysis of Petro-Physico-Mechanical Properties of Coarse Aggregate and Its Implications on the Performance Characteristics of Concrete

2020 ◽  
pp. 45-60
Author(s):  
Larry Pax Chegbeleh ◽  
Lawrence Opanin Nkansah ◽  
Frank Siaw Ackah ◽  
Richard Adams Mejida
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Coarse Aggregate ◽  
Aggregate Size ◽  
Performance Characteristics ◽  
Rock Samples ◽  
Rock Types ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
The Impact

The importance of concrete as one of the major materials in the building and construction industry cannot be over emphasized due to the myriad benefits and versatility to humankind. However, its performance characteristics on the stability of engineered structures have mostly been overlooked. In this paper, petrographic characteristics and physico-mechanical properties of ten (n=10) rock samples and some quantity of coarse aggregate representing one set of samples, each obtained from two quarry sites around Amasaman and Shai Hills in the Greater Accra Region of Ghana, have been investigated. This study aimed to determine the impact of aggregate size, content and type on the compressive strength of concrete. The study was conducted through petrographic and physico-mechanical properties analyses on the samples obtained. Petrographic studies were performed on the ten (n=10) rock samples from each quarry site, while the physico-mechanical property tests were conducted directly on the coarse aggregate. However, compressive strength tests were performed on cast concretes produced from aggregates with varying sizes and type obtained from the two quarry sites. Results of the petrographic analysis reveal two rock types: Quartzo-feldspathic gneiss and Granodiorites from Amasaman quarry and also two rock types: Gneiss and Meta-granite from Shai Hills quarry. Results of the physico-mechical properties tests are consistent with requirement of approved construction standards. Compressive strength tests show increasing compressive strength of concretes with increasing aggregate nominal sizes of classes A, B and C but show reduced compressive strength for aggregate nominal sizes of class D. It can therefore, be inferred that, aggregate size and content have profound impact on compressive strength of concrete. Also, aggregate type has influence on compressive strength of concrete, as observed in higher compressive strength of concretes produced from the quartzo-feldspathic gneiss and granodiorites than concretes produced from the gneiss and meta-granites.

scholarly journals Pengaruh Cangkang Kerang Laut Terhadap Kuat Tekan Beton

2021 ◽  
Vol 2 (1) ◽  
pp. 46-54
Author(s):  
Neti Rahmawati ◽  
Irwan Lakawa ◽  
Sulaiman Sulaiman
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Building Materials ◽  
Coarse Aggregate ◽  
Fine Aggregate ◽  
Fine Aggregates ◽  
Concrete Quality ◽  
Compressive Strength Of Concrete ◽  
Physical Construction

Concrete is one of the most widely used building materials today interms of physical construction. Concrete is made from a mixture offine, coarse aggregate, cement, and water with a certain ratio, aswell as materials that are usually added to the concrete mixtureduring or during mixing, to changing the properties of concrete tomake it more suitable in certain jobs and more economical, can alsobe added with certain other mixed materials as needed if deemednecessary. Seashells can be used to mix concrete. This study aims todetermine whether the addition of shells aggregate shells in aconcrete mixture can affect the mechanical properties of concrete.The specimens used are in the form of cubes with a size of 15cm x 15cm x 15 cm, consisting of additional concrete coarse and fineaggregate with shell substitution percentage of 0%, 15%, 20% with atotal sample of 45, with the planned concrete quality of K225. Theuse of sea shells in increasing the compressive strength of concrete isbetter used as fine aggregate than coarse aggregate. The use of seashells as a substitute for fine aggregates achieves maximum resultsat 20% composition.

scholarly journals Study on Strength Properties of Concrete with Ceramic Waste Aggregate and Silica Fume Admixture

2018 ◽  
Vol 7 (3.12) ◽  
pp. 831
Author(s):  
Suresh G ◽  
Harishankar S
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Silica Fume ◽  
Coarse Aggregate ◽  
Strength Properties ◽  
Industrial Wastes ◽  
Conventional Concrete ◽  
Ceramic Waste ◽  
Compressive Strength Of Concrete

The ceramic waste is used as a coarse aggregate replacement in concrete is a two way beneficial process that involves minimization of resources for construction and processing of hazardous industrial wastes that cannot be recycled. The ceramic waste obtained from waste dismantled building were used as coarse aggregate 10%, 20%, 30%, 40% and 50% replacement.  To improve the mechanical properties silica fume is added as admixture in the concrete. The optimum percentage replacement was obtained considering the strength as well as the objective of using ceramic waste aggregate. The compressive strength of concrete cubes were tested . The compressive strength of aggregate replaced concrete has been compared to that of conventional concrete and the results are evaluated. 

scholarly journals Experimental Evaluation of the Effect of Silica Fume on Compressive, Tensile Strength, Abrasion Resistance, Slump and Impact Test and Water Permability Coefficient of Concrete

2018 ◽  
Vol 8 (1) ◽  
pp. 27-36
Author(s):  
M. Esmailpour ◽  
K. Rahmani ◽  
S. Piroti
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Silica Fume ◽  
Impact Test ◽  
Surface Cracks ◽  
Strength Parameters ◽  
Ordinary Concrete ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Positive Effect

Abstract The use of various additives (admixtures) in concrete and cement products has been considered by various researchers in recent years. Microsilica (Silica fume) can also be considered as one of the most widely used additives (admixtures) in this section. In this study, 120 concrete specimens were constructed using a mix design based on ACI in the laboratory with an overview of records and advantages of using microsilica in concrete. The microsilica used in concrete specimens has been considered 2%, 5.5% and 7.5% by weight of cement. Finally impact permeability, tension and uniaxial compressive strength tests were done on concrete specimens and their mechanical properties were evaluated. The results show that microsilica improves the mechanical properties of concrete. The results also show that the use of microsilica in ordinary concrete has a very positive effect in controlling the surface cracks and increasing some strength parameters such as tensile and compressive strength of concrete.

scholarly journals Compressive strength of re-vibrated concrete made from pebbles

2020 ◽  
Vol 211 ◽  
pp. 03007
Author(s):  
Auta Samuel Mahuta ◽  
Peter Emmanuel Aku
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Time Lag ◽  
Target Strength ◽  
Coarse Aggregates ◽  
Strength Tests ◽  
Compressive Strength Of Concrete ◽  
Ongoing Development ◽  
Vibration Time ◽  
Curing Age

The search for natural and readily available structural material to meet the growing demand for ecologically friendly and smart structures is an ongoing development. In this background, an experimental study into the compressive strength of re-vibrated concrete made from pebbles as coarse aggregate is presented. Fifty-six (56) concrete cubes were cast adopting a re-vibration time lag interval of 10minutes for one hour, with a target strength of 15N/mm2. This comprised 28 cubes 100% granite and 28 cubes 100% pebbles as coarse aggregates respectively. Two curing ages were considered: 7 and 28 days. Results from the compressive strength tests of the cured specimens showed that: at successive time lag intervals there was an appreciable rise in compressive strength of concrete; observable was also a rise in the compressive strength with an increase of curing age. However, even though the maximum compressive strength of 25.64N/mm2 for 100%granite was achieved, that of 100%pebbles attained 23.33N/mm2, both at 60th minute of re-vibration time lag respectively. Hence, it can be suggested that 100% pebbles replacement for granite can be used to produce concrete with compressive strength of up to 23N/mm2 when revibrated.

IMPACT OF COARSE AGGREGATE ON COMPRESSIVE STRENGTH OF CONCRETE

2019 ◽  
Vol 16 (1) ◽  
pp. 52
Author(s):  
Jeriscot H. Quayson ◽  
Zakari Mustapha
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Average Density ◽  
Fine Aggregate ◽  
Coarse Aggregates ◽  
Crushed Granite ◽  
Compaction Factor ◽  
Compressive Strength Of Concrete ◽  
The Individual ◽  
The Impact

Over one-third of the volume of concrete is occupied by coarse aggregate and any changes in coarse aggregate type can affect its strength and fracture properties. The paper examined the impact of coarse aggregates on compressive strength of concrete. Slump and compaction factor tests were conducted on the mixture of quartzite and crushed granite course aggregates, and quarry dust (fine aggregate). Nominal mix (1:2:3) was adopted and mix compositions were calculated by absolute weight method. Twelve (12) cubes (150x150mm) of each type of coarse aggregate were cast for 7, 14, 21, and 28 days to determine their compressive strengths. Quartzite was found to have the highest average compressive strength of 24.48N/mm2 with an average density of 2160kg/m3 , while compressive strength of crushed granite was 22.01N/mm2 with an average density of 2300kg/m3 on the 28 day of testing. Concrete made from granite had the highest workability, while concrete made from quartzite aggregate had the highest compressive strength. Densities and compressive strengths of the individual aggregates accounted for the variation in strengths of the concrete, due to differences in properties and strengths. In conclusion, the effect of any type of coarse aggregate on the compressive strength of concrete will be known and also enable contractors to determine the type of aggregate to be selected for a particular work. Keywords: Compaction factor test; slump test; strength; workability.

scholarly journals Investigation on Properties of Cement Bitumen Emulsion Mortars (CBEM) in Consideration of Emulsifier Types

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Zhuoran Liu ◽  
Jinyang Huo ◽  
Zhenjun Wang
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Viscoelastic Property ◽  
Low Frequency ◽  
Dynamic Mechanical Analyzer ◽  
Bitumen Emulsion ◽  
Strength Tests ◽  
Before And After ◽  
The Impact ◽  
Better Than

In order to investigate the influences of emulsifier types on properties of cement bitumen emulsion mortars (CBEM), anionic and cationic emulsifiers were used to prepare CBEM in this work. Influences of anionic and cationic bitumen emulsions on workability, mechanical properties, and viscoelastic property of CBEM were studied. The workability of CBEM was evaluated by fluidity and extensibility tests. The mechanical properties were assessed by compressive strength and flexural strength tests. XRD was used to analyze the phase before and after bitumen emulsion was added. The viscoelastic property was studied by a dynamic mechanical analyzer (DMA). The results show that CBEM prepared by cationic bitumen emulsion (CBE) has better workability. The mechanical properties of CBEM are negatively affected by bitumen emulsion. The impact on the compressive strength of CBEM prepared by CBE is higher. Bitumen emulsion can significantly improve the viscoelastic property of CBEM. With the increase of bitumen emulsion dosage, the loss factor of CBEM increases. The viscoelastic property at low frequency is better than that at high frequency. In contrast to CBEM prepared by CBE, CBEM prepared with anionic bitumen emulsion (ABE) possesses better viscoelastic property.

scholarly journals Studi Mengenai Perlakuan Agregat Berukuran 2,38 mm ­ 4,75 mm sebagai Agregat Kasar dalam Campuran Beton (Hal. 22-31)

2018 ◽  
Vol 4 (4) ◽  
pp. 22
Author(s):  
Ahmad Ramdani ◽  
Priyanto Saelan
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Aggregate Size ◽  
Self Compacting Concrete ◽  
Cylinder Diameter ◽  
Strength Tests ◽  
Concrete Mix ◽  
Crushed Aggregate

ABSTRAKBatu pecah berukuran 2,38 mm – 4,75 mm tidak digunakan dalam campuran beton. Jika campuran beton dirancang menggunakan batu pecah ini sebagai agregat kasar, maka campuran beton yang dihasilkan diduga tidak akan mengalami segregasi untuk semua kelecakan, lebih homogen, dan jika diberi bahan tambahan superplasticizer diduga dapat dengan mudah berperilaku sebagai campuran beton memadat mandiri. Penelitian ini dilakukan untuk membuktikan dugaan tersebut. Penelitian dilakukan dengan kuat tekan rencana 30 MPa, slump 40 mm dan 100 mm, tanpa dan dengan bahan tambahan superplasticizer dengan dosis 1% dan 1,5%. Perancangan campuran beton dengan cara Dreux menggunakan faktor granular 0,40; 0,45; 0,50; dan 0,55. Pengujian kuat tekan pada benda uji silinder diameter 10 cm dan tinggi 20 cm membuktikan bahwa dugaan tersebut adalah benar, dan perancangan campuran beton dengan memperlakukan batu pecah berukuran 2,38 mm – 4,75 mm sebagai agregat kasar dapat dilakukan untuk faktor granular 0,40 – 0,50.Kata kunci: batu pecah berukuran 2,38 mm – 4,75 mm,agregat kasar,superplasticizer ABSTRACT2.38 mm – 4.75 mm crushed aggregate size is not used in concrete mix. If this crushed aggregate is used as coarse aggregate, the resulting concrete mix is assumed will not segregate in all workability, more homogeneous, and it will behave easily as self-compacting concrete by adding superplasticizer. This research was conducted to prove these assumption. Concrete mix with compressive strength of 30 MPa, 40 mm and 100 mm slump is made using Dreux method with granular factor 0.40; 0.45; 0.50; and 0.55. The doses of superplasticizer is 1% and 1.5% by cement weight. Compressive strength tests of 10 cm diameter and 20 cm height cylinder diameter showed these assumption is true, and concrete mix can be designed using granular factor 0.40 – 0.50.Keywords: 2,38 mm – 4,75 mm crushed aggregate size, coarse aggregate, superplasticizer

scholarly journals Effects of Uncrushed Aggregate on the Mechanical Properties of No-Fines Concrete

2018 ◽  
Vol 8 (3) ◽  
pp. 2882-2886 ◽  
Author(s):  
M. A. Memon ◽  
M. A. Bhutto ◽  
N. A. Lakho ◽  
I. A. Halepoto ◽  
A. N. Memon
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Coarse Aggregate ◽  
Lightweight Concrete ◽  
Aggregate Size ◽  
Unit Weight ◽  
Conventional Concrete ◽  
Major Aspect ◽  
Coarse Aggregates ◽  
Cellular Concrete

Concrete’s self-weight is a major aspect of a structure’s overall weight. Recently, the use of lightweight concrete (no-fines, foamed and cellular concrete) has been increased. Normally no-fines concrete is produced with crushed coarse aggregate of uniform gradation. This study aims to investigate experimentally the effects of the use of uncrushed coarse aggregates on unit weight, compressive and tensile strength of the no-fines (NFC) as well as conventional concrete (CC). In addition, the effects of coarse aggregate size on the mechanical properties were also studied. Four gradations of uncrushed coarse aggregates ranging between (5.5-4.75) mm, (10-4.75) mm, (20-4.75) mm and (25-4.75) mm were used for preparing the concretes. The fixed cement-aggregate ratios of 1:6 (with w/c ratio=0.4) and 1:2:4 (with w/c ratio=0.5) were adopted for NFC and CC respectively. It was found that the gradation of uncrushed coarse aggregate has a significant effect on the mechanical properties of NFC. A maximum of 16% reduction in self-weight of the concrete without fines was obtained, as compared to that with fines. Moreover, the compressive strength of no-fines concrete significantly improved by replacing crushed with uncrushed coarse aggregate. The compressive strength increased by 16% for the batch of (25-4.75) mm.

Experimental Research on the Influence of Grain Size of Coarse Aggregate on Pebble Concrete Compressive Strength

2012 ◽  
Vol 238 ◽  
pp. 133-137 ◽  
Author(s):  
Wei Xie ◽  
Ya Nan Jin ◽  
Shu Shan Li
Keyword(s):  
Grain Size ◽  
Compressive Strength ◽  
Size Effect ◽  
Experimental Research ◽  
Coarse Aggregate ◽  
Aggregate Size ◽  
Maximum Size ◽  
Concrete Compressive Strength ◽  
Cement Ratio ◽  
Strength Tests

To discuss the influence of coarse aggregate size, water cement ratio and ages on the concrete compressive strength，the compressive strength tests were carried out by 54 cubic specimens of pebbles concrete in dimensions of 150mm, 18 cubic specimens with dimensions of 200mm and 72 specimens with size of 150mm×150mm×300mm. The results show that the maximum size of coarse aggregate rises with the decrease of the concrete compressive strength; Concrete compressive strength of coarse aggregate size affects more apparently as the ratio of water-cement decrease; with the increasing of age, concrete compressive strength of the aggregate size effect has no significant changes.

Effect of combined drink cans and steel fibers on the impact resistance and mechanical properties of concrete

2020 ◽  
Vol 14 (2) ◽  
pp. 6734-6742
Author(s):  
A. Syamsir ◽  
S. M. Mubin ◽  
N. M. Nor ◽  
V. Anggraini ◽  
S. Nagappan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Reinforced Concrete ◽  
Impact Resistance ◽  
Fiber Reinforced Concrete ◽  
Steel Fibers ◽  
Fiber Reinforced ◽  
Indirect Tensile ◽  
The Impact

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study.  The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.    

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