scholarly journals Lightweight self-compacting concrete with sintered fly-ash aggregate

2018 ◽  
Vol 27 (3) ◽  
pp. 328-337
Author(s):  
Dorota Małaszkiewicz ◽  
Daniel Jastrzębski
Keyword(s):  
Fly Ash ◽  
Fresh Concrete ◽  
Strength Loss ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Self Compacting Concrete ◽  
Natural Sand ◽  
Concrete Properties ◽  
Slump Flow ◽  
Passing Ability

The article presents the results of research assessing the possibility of making LWSCC from the locally produced sintered fly ash aggregate CERTYD. Two methods of preliminary LWA preparation were applied: pre-soaking with water and coating with a film of cement paste. The following properties of fresh LWSCC were evaluated: slump-flow, time T500 and passing ability using L-Box. Partial replacement of natural sand by fine LW sand (0/0.5 mm) improved filling and passing abilities of fresh concrete, reduced slightly the bulk density, but it resulted in compressive strength loss by 12-18%. In terms of both fresh and hardened concrete properties it is more favorable to use only fine LW sand as natural sand replacement. Considering fresh concrete properties paste impregnation of LW aggregate is more efficient than saturation with water.

scholarly journals Experimental study on potential use of fly ash and GGBS from Jaipur plants in developing a self-compacting concrete

2018 ◽  
Vol 7 (4.5) ◽  
pp. 566
Author(s):  
Sushree Sangita Rautray ◽  
Manas Ranjan Das
Keyword(s):  
Fly Ash ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Self Compacting Concrete ◽  
Split Tensile Strength ◽  
Granulated Blast Furnace Slag ◽  
Slump Flow ◽  
Filling Ability ◽  
Essential Properties ◽  
Passing Ability

Self-Compacting Concrete (SCC) is becoming a popular choice in concrete industries due to its filling ability in congested reinforcement and its auto compacting nature. In the present work, an attempt has been made to investigate the properties of fresh and hardened concrete made by partial replacement of cement by fly ash and ground granulated blast furnace slag (ggbs) in different percentages. The essential properties of freshly prepared concrete like flowability, passing ability, filling ability are determined by slump flow test, slump flow T50cm, V-funnel, J-ring and L-box test. The values are found to satisfy EFNARC guidelines. Tests have also been conducted to assess and analyze the properties of hardened concrete such as compressive strength, split tensile strength and flexural strength. Thus an attempt has been made to develop a formulation of an economically feasible and environment friendly self-compacting concrete.   

Rice Husk Ash as Fine Aggregate Sustainable Material for Strength Enhancement of Conventional and Self Compacting Concrete

2016 ◽  
Vol 692 ◽  
pp. 94-103
Author(s):  
S.S. Samantaray ◽  
K.C. Panda ◽  
M. Mishra
Keyword(s):  
Rice Husk ◽  
Rice Husk Ash ◽  
Fresh Concrete ◽  
Partial Replacement ◽  
Hardened Concrete ◽  
Fine Aggregate ◽  
Self Compacting Concrete ◽  
Strength Enhancement ◽  
Slump Flow ◽  
Concrete Property

Rice husk ash (RHA) is a by-product of the rice milling industry. Near about 20 million tonnes of RHA is produced annually which creates environmental pollution. Utilization of RHA as a supplementary cementitious material adds sustainability to concrete by reducing CO2 emission of cement production. But, the percentage of utilization of RHA is very less. This paper presents the results of an experimental investigation to study the effects of partial replacement of fine aggregate with RHA on mechanical properties of conventional and self-compacting concrete (SCC). The fine aggregate is replaced by RHA in conventional concrete (CC) with six different percentage by weight such as 0%, 10%, 20%, 30%, 40% and 50% having w/c ratio 0.375 with variation of super plasticiser dose, whereas in SCC the replacement of fine aggregate by RHA is 0%, 10%, 20%, 30%, 40%. The design mix for CC is targeted for M30 grade concrete. The fresh concrete test of SCC is conducted by using slump flow, T500, J-ring, L-box, U-box and V-funnel to know the filling ability, flow ability and passing ability of SCC. As fresh concrete property concerned, the result indicates that the slump flow value satisfied the EFNARC 2005 guidelines upto 30% replacement of fine aggregate with RHA whereas 40% replacement did not satisfy the guideline. As hardened concrete property concerned, the compressive strength, split-tensile strength and flexural strength of CC and SCC are determined at 7, 28 and 90 days. The test result indicates that upto 30% replacement of fine aggregate with RHA enhances the strength in CC whereas the strength enhancement in SCC upto 20% replacement.

scholarly journals Comparative Study of Self-Compacting Concrete Containing Lightweight and Normal Aggregates

2019 ◽  
Vol 27 (2) ◽  
pp. 1-8
Author(s):  
Ramamohanrao Pannem ◽  
Padmaja P. Kumar
Keyword(s):  
Fly Ash ◽  
Fresh Concrete ◽  
Void Content ◽  
Self Compacting Concrete ◽  
Simple Method ◽  
Coarse Aggregates ◽  
Concrete Properties ◽  
Round Shape ◽  
Fine Aggregates ◽  
Ash Aggregates

AbstractBased on the available literature, a simple method was adopted to calculate the packing density of aggregates and thereby reduce their void content by optimising their packing aggregates and by using two different sizes of coarse aggregates and fine aggregates. This study provides an understanding of the way in which the shape of aggregates affects the properties of self-compacting concrete (SCC). The fresh, hardened, and durable properties of SCC with normal and lightweight fly ash coarse aggregates are found at the corresponding age of the curing. Their values were compared with respect to SCC containing normal aggregates. A mix with fly ash aggregates was found to have better fresh concrete properties due to the round shape of the aggregates. After the packing of the aggregates, this mix was found to have better mechanical and durability properties than all the other concrete mixes.

scholarly journals Development of An Environmental-Friendly Durable Concrete

2021 ◽  
Author(s):  
DEEP TRIPATHI ◽  
Rakesh Kumar ◽  
Pradeep Kumar Mehta
Keyword(s):  
Compressive Strength ◽  
Structural Changes ◽  
Fresh Concrete ◽  
Tap Water ◽  
Partial Replacement ◽  
Natural Sand ◽  
Environment Friendly ◽  
Manufactured Sand ◽  
Slump Flow ◽  
Micro Level

Abstract In this experimental study on Self Compacting Concrete (SCC), the Manufactured sand (M-sand) and Fly ash (FA) were utilised for partial replacement of Natural sand (N-sand) and Ordinary Portland Cement (OPC), respectively. N-sand was partially replaced by M-sand at various percentage levels, after the dose of FA in the mix was optimized. In terms of compressive strength, the optimum replacement level of OPC by FA was 20%, while for replacement of N-sand by M-sand it was 50%. Two types of mixes were made to compare the macro and micro level properties of SCC, i.e., SCC-I (100%OPC+100%N-sand), and SCC-II (80%OPC+20%FA+50%N-sand+50%M-sand). The characteristics of fresh concrete mixes were determined using Slump flow, T50 time, V-funnel, L-box, U-box, and J-ring tests. After 28 days of curing in tap water, both type of specimens were exposed in solution of Ammonium Sulphate [(NH4)2SO4] containing Sulphate salt concentration of 2.0g/l for 360 days to test their durability. Loss in compressive strength, weight change, sorptivity, and micro-structural changes (XRD, SEM, and EDS) all were evaluated up to 360 days. It was found that the use of FA and M-sand in concrete makes it more environment friendly and durable, as well as having higher performance in a sulphate environment.

scholarly journals EVALUATION OF SUITABILITY TO USE PLASTIC WASTE IN CONCRETE PRODUCTION

2018 ◽  
Author(s):  
Rytis SKOMINAS ◽  
Linas ZVINAKEVIČIUS ◽  
Vincas GURSKIS ◽  
Raimondas ŠADZEVIČIUS
Keyword(s):  
Compression Strength ◽  
Fresh Concrete ◽  
Strength Loss ◽  
Plastic Waste ◽  
Hardened Concrete ◽  
Coarse Aggregates ◽  
Concrete Properties ◽  
Concrete Production ◽  
Negative Effect ◽  
Water Absorbability

Nowadays one of the main tasks of environmental protection is the management and recycling of plastic waste. Plastic occupy the major part of all public waste and with this material is polluted all earth. In natural condition plastic decompose in 400 or even in 500 years. Therefore, it is important to solve this problem reusing plastic waste. One of the possible areas is construction industry. In the present paper were estimated how plastic waste impact the properties of concrete. During the research the part of coarse aggregates were changed with polyethylene (PE) pellets and cut polypropylene (PP) particles. The change of fresh concrete density, workability and hardened concrete density, compression strength, water absorbability were evaluated. The results show, that plastic waste has a positive effect on fresh concrete properties: the concrete become more workable and lighter. Unfortunately, on the main hardened concrete properties the increase plastic waste amount has the negative effect: the compression strength was decreasing and the water absorbability was increasing. However, generalizing all results, can be stated, that keeping the same level of concrete workability there are possibilities to reduce water and cement ratio and it will give strength loss and water absorbability growth compensation.

Application of Fly Ash and Brick Dust as a Suitable Materials for Fine Aggregate in Self-Consolidating Concrete

2019 ◽  
Author(s):  
Phani N. Ramamurthy
Keyword(s):  
Fly Ash ◽  
Large Scale ◽  
Engineering Properties ◽  
Dry Density ◽  
Hardened Concrete ◽  
Fine Aggregate ◽  
Skilled Workers ◽  
Construction Sites ◽  
Self Compacting Concrete ◽  
Natural Sand

Large-scale efforts are needed for conservation of natural sand whose resources are reducing day by day and legal complications are making it difficult to meet the demand. So, self-compacting concrete (SCC) is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement. The hardened concrete is dense, homogeneous and has the same engineering properties and durability as traditional vibrated concrete. Complex shape of concrete structures and densely arranged bars make it more difficult to use a vibrator. Vibratory compaction is noisy and deleterious to the health of construction workers, as well as an annoyance to people in the neighborhood. In remote areas it is difficult to find skilled workers to carry out the compacting work at construction sites. This paper presents the progress of the research on different harden properties of Self Compacting Concrete using the Ordinary Portland Cement “Ultratek” made and low-calcium fly ash from Birla Glass, Kosamba, Gujarat, as binder materials in making the concrete mixes along with other ingredients locally available. Results indicated increase in workability for all the cases over control concrete. Concrete with fly ash was also found to be about 25% economical when cost per N/mm2 was compared. Based on experimental results correlations are developed to predict Compressive Strength, Flexural strength, cost, Slump and Dry Density for percentage sand replacement with fly ash. Available online at https://int-scientific-journals.com

Concrete with High Content of Fly Ash Intended for Constructions with Long Durability

2016 ◽  
Vol 249 ◽  
pp. 21-27 ◽  
Author(s):  
Adam Hubáček ◽  
Rudolf Hela
Keyword(s):  
Compressive Strength ◽  
Czech Republic ◽  
Fly Ash ◽  
Fresh Concrete ◽  
Ash Content ◽  
Hardened Concrete ◽  
The Czech Republic ◽  
Concrete Properties ◽  
Pressure Water ◽  
Long Life

The article deals with theme of high fly ash content concretes intended for long life constructions. Considering the still growing consumption of fly ash in construction concretes it is a live theme in the Czech Republic and abroad as well. The emphasis will be laid namely on characteristics and requirements for fresh concrete intended for construction of these specific concrete constructions. They are for instance waterproof constructions, tunnel linings, concretes for bridge and road constructions etc. Also the hardened concrete properties like compressive strength, resistance to pressure water, durability and further necessary parameters for obtainment of required properties of these concretes will be monitored.

Performance and Uniformity of Self-Compacting Concrete

2005 ◽  
Vol 1914 (1) ◽  
pp. 71-80
Author(s):  
Mohamed Nagib Abou-Zeid ◽  
Mohamed Samir Roushdy
Keyword(s):  
Coarse Aggregate ◽  
Fresh Concrete ◽  
Mechanical Vibration ◽  
Hardened Concrete ◽  
Fine Aggregate ◽  
Self Compacting Concrete ◽  
Rebound Hammer ◽  
Slump Flow ◽  
Hardened Properties ◽  
The Impact

Self-compacting concrete (SCC) can be achieved by adjusting mix proportions and incorporating adequate admixtures, such as viscosity-modifying (VM) admixtures, with no vibration. Yet, the impact of the mix proportions and the role played by the VM admixtures as opposed to those played by superplasticizer admixtures are not fully understood. There also seems to be no unique means for assessment of such concrete, and the correlation between various tests needs further work. This study aims to achieve a better understanding of the influence of mix proportions on the properties of SCC. Twenty-six mixtures were prepared with various water-to-cementitious material ratios, fine aggregate-to-coarse aggregate ratios, and admixture dosages. Fresh concrete tests, including slump flow, L-box, U-box, and hardened concrete tests, including hardened density, compressive and flexural strength, as well as the rebound hammer tests, were performed. The uniformity of SCC properties among the column specimens was examined. The results revealed that adjustment of the mix proportions has a major impact on the fresh and hardened properties of SCC. The fresh concrete tests were found to correlate well with one another, and the SCC strength was comparable to that of reference concrete made with mechanical vibration. Yet, the components of the SCC examined exhibited a remarkable uniformity of properties. Further work that should involve large specimens in which concrete properties are evaluated in various locations is needed.

scholarly journals Valorization of fly ash from a thermal power plant for producing high-performance self-compacting concrete

2020 ◽  
Vol 52 (3) ◽  
pp. 307-327
Author(s):  
Aleksandar Savic ◽  
Milica Vlahovic ◽  
Sanja Martinovic ◽  
Natasa Djordjevic ◽  
Gordana Broceta ◽  
...  
Keyword(s):  
Fly Ash ◽  
Power Plant ◽  
Thermal Power Plant ◽  
High Performance ◽  
Positive Impact ◽  
Thermal Power ◽  
Sem Analysis ◽  
Partial Replacement ◽  
Self Compacting Concrete ◽  
Slump Flow

This study analyzes the feasibility of valorizing industrial by-product, fly ash from a thermal power plant as a partial replacement of mineral filler-limestone for the production of self-compacting concrete (SCC). Three types of SCC mixtures with different portions of fly ash and the reference mixture with limestone were designed. The synthesized SCCs in the fresh state were examined for density, entrained air content, flowability (Slump flow, Slump flow time (t500), V-funnel time (tv)), passing ability (L-box), and segregation resistance, while hardened state testing included: density, compressive and flexural strength, static modulus of elasticity, water permeability, resistance against freezing in the presence of de-icing salt, and SEM analysis. Taking into account the obtained results it can be concluded that the addition of fly ash has a positive impact on the concrete properties and that the optimal content of fly ash is 20 % with respect to the total filler mass.

Effect of basalt, polypropylene and macro-synthetic fibres on workability and mechanical properties of self-compacting concrete

2019 ◽  
Vol 5 (2) ◽  
pp. 35
Author(s):  
Zinnur Çelik ◽  
Ahmet Ferhat Bingöl
Keyword(s):  
Mechanical Properties ◽  
Fresh Concrete ◽  
The Self ◽  
The Other ◽  
Fibre Content ◽  
Hardened Concrete ◽  
Fibre Reinforced Concrete ◽  
Self Compacting Concrete ◽  
Concrete Properties ◽  
Hardened Properties

In this study, the effects of different fibre types on the workability and mechanical properties of self-compacting concrete were investigated. Fresh and hardened properties of self-compacting concrete, different fibre content 0.90, 1.35 and 1.80 kg/m3 were evaluated using basalt, polypropylene and macro synthetic fibres with different fibre lengths of 24, 19 and 40 mm, respectively. The properties of fresh concrete were evaluated in terms of slump flowing, viscosity and flowability. In addition, compressive, flexural and splitting tensile strength were obtained from hardened concrete properties. To characterize mechanical properties 90 specimens were experimentally tested. The results show that the use of fibre reduces the workability of self-compacting concrete. On the other hand, tensile and flexural strength of the self-compacting fibre reinforced concrete increased with increasing fibre content, but it was determined that the fibre addition had no significant effect on the compressive strength.

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