scholarly journals A study of packing parameters that influence the fresh properties of self-compacting concrete

Cerâmica ◽  
2019 ◽  
Vol 65 (375) ◽  
pp. 432-442
Author(s):  
C. V. A. de Melo ◽  
P. C. C. Gomes ◽  
K. A. M. Moraes
Keyword(s):  
Distribution Coefficient ◽  
Fine Particles ◽  
The Self ◽  
Void Content ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Coarse Aggregates ◽  
Slump Flow ◽  
Fresh State

Abstract Some known self-compacting concrete (SCC) mix-designs are based on the lowest void content as a purpose of an ideal packing. However, a composition with a lower void content is not a guarantee of good synergy between the largest and smallest grain in the fresh state. The purpose of this study was to identify and evaluate different packing parameters in the aggregates gradations that influence on the self-compactability. Nine aggregates combinations (4 binaries, 4 ternaries and 1 quaternary) were used for determination of nine gradations. Tests as slump-flow, L-box and V-funnel were used. The distribution coefficient (q) was determined by the Alfred model. The results showed that not all values of q (between 0.201 and 0.253) attended the values given for SCC, and the gradations with the lowest difference among the coarse and fine particles, higher void content, continuous distributions and 50% of coarse aggregates had better performance.

scholarly journals Towards Sustainable Self-Compacting Concrete: Effect of Recycled Slag Coarse Aggregate on the Fresh Properties of SCC

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Hisham Qasrawi
Keyword(s):  
Steel Industry ◽  
Coarse Aggregate ◽  
Steel Slag ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Air Content ◽  
Coarse Aggregates ◽  
Slump Flow ◽  
Natural Aggregates ◽  
The Impact

Steel industry results in accumulation of steel slag wastes causing severe environmental problems. These wastes can be recycled and replace natural aggregates resulting in sustainable green concrete. In this research, natural aggregates in self-compacting concrete (SCC) are replaced, wholly or partly, by steel slag coarse aggregates that were produced by crushing by-product boulders obtained from the steel industry. Fresh properties, (workability, stability, bleeding, air content, and fresh density) are the crucial ones that affect the final properties of SCC. Therefore, it becomes important to evaluate the impact of SSA on the fresh properties of SCC mixes. The properties that are studied include stability, flowability, blocking, segregation, and bleeding. Furthermore, air content and fresh density are measured. In order to evaluate the impact of SSA on SCC properties, several testing methods are employed. Slump flow, V-funnel, column segregation, sieve segregation, segregation probe, U-shaped box, and VSI tests have been used in the study. The results show that it is possible to produce SCC using steel slag aggregate. Hence, green sustainable SCC can be produced. The results show that the fresh properties become sensitive for SSA replacement ratios exceeding 50%.

Rheological Behavior of Self-Compacting Geopolymer Concrete Containing Recycled Aggregates: Effect of Na2SiO3/NaOH and Molarity of NAOH

2021 ◽  
Vol 872 ◽  
pp. 79-84
Author(s):  
Koran Salihi ◽  
Khaleel H. Younis
Keyword(s):  
Sodium Hydroxide ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Geopolymer Concrete ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Sustainable Concrete ◽  
Coarse Aggregates ◽  
Concrete Mixtures ◽  
Fresh State

To develop a sustainable concrete and to minimize the depletion of the natural resources, an attempt was made to develop sustainable concrete mixtures benefiting from the geopolymer technology and the use of recycled aggregate in self-compacting geopolymer concrete (SCGC). This study aim to examine the effects of sodium hydroxide (SH) molarity and sodium silicate (Na2SiO3)/ sodium hydroxide (SS/SH) ration the fresh properties of SCGC mixtures containing recycled coarse aggregates (RCA) Mixes were prepared with three different molarity (8M, 10M and 12M) of) and four SS/SH ratios (1.5, 2.0, 2.5 and 3.0). Six mixes were examined in this study. The results were compared with the EFNARC limits for self-compacting concrete (SCC). It was found that the SS/SH ratio and the molarity of SH affect the fresh properties of (SCGC). However, the results showed that, SCGC mixtures containing RCA can be developed and satisfy the requirements of EFNARC for fresh state of SCC.

scholarly journals Effect of Fly Ash and Un-crushed Coarse Aggregates on Characteristics of SCC

2020 ◽  
Vol 6 (4) ◽  
pp. 693-701 ◽  
Author(s):  
Muneeb Ayoub Memon ◽  
Noor Ahmed Memon ◽  
Bashir Ahmed Memon
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Coarse Aggregate ◽  
Flow Time ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Coarse Aggregates ◽  
Slump Flow ◽  
Crushed Aggregate ◽  
Better Than

This research paper discusses the change in the workability and strength characteristics of Self Compacting Concrete (SCC) due to addition of fly-ash and use of un-crushed Coarse Aggregate (CA). Laboratory based experimental work was carried out by preparing 12 SCC mixtures among which six mixtures contained crushed aggregate and other six mixtures contained un-crushed coarse aggregate. A total of 550 kg/m3 binder content and fixed Water-Binder (W/B) ratio as 0.35 were used. Two mixtures were controlled by using Portland Cement (PC) and other ten mixtures contained PC and Fly Ash (FA). Slump flow time, slump flow diameter and J-ring height tests were conducted to study the fresh properties of SCC. Furthermore, compressive strength was calculated at 7, 14 and 28 days of curing. The outcomes indicated that the slump flow time, slump flow diameter and J-Ring height for all the mixes are within the limits specified by EFNARC guidelines. The compressive strength of SCCs depends upon dosage of fly ash. Compressive strength for SCCs with crushed CA was better than obtained in case of un-crushed CA. The maximum compressive-strengths were observed as 64.58 MPa and 58.05 MPa for SCC with crushed and un-crushed CA respectively.

Fresh, Durability and Mechanical Behavior of Self Consolidating Concrete Incorporating Fly Ash and Admixture under Hot Weather

2021 ◽  
Vol 904 ◽  
pp. 453-457
Author(s):  
Samer Al Martini ◽  
Reem Sabouni ◽  
Abdel Rahman Magdy El-Sheikh
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Absorption ◽  
Weather Conditions ◽  
Chloride Penetration ◽  
The Self ◽  
Fresh Properties ◽  
Self Consolidating Concrete ◽  
Slump Flow ◽  
Hot Weather

The self-consolidating concrete (SCC) become the material of choice by concrete industry due to its superior properties. However, these properties need to be verified under hot weather conditions. The paper investigates the behavior of SCC under hot weather. Six SCC mixtures were prepared under high temperatures. The SCC mixtures incorporated polycarboxylate admixture at different dosages and prolonged mixed for up to 2 hours at 30 °C and 40 °C. The cement paste was replaced with 20% of fly ash (FA). The fresh properties were investigated using slump flow, T50, and VSI tests. The compressive strength was measured at 3, 7, and 28 days. The durability of SCC mixtures was evaluated by conducting rapid chloride penetration and water absorption tests.

Fresh Properties of Self-Compacting Concrete Integrating Coal Bottom Ash as a Replacement of Fine Aggregates

2015 ◽  
Vol 1125 ◽  
pp. 370-376
Author(s):  
Ahmad Farhan Hamzah ◽  
Mohd Haziman Wan Ibrahim ◽  
Norwati Jamaluddin ◽  
Ramadhansyah Putra Jaya ◽  
Norul Ernida Zainal Abidin
Keyword(s):  
Bottom Ash ◽  
Resistance Index ◽  
Ash Content ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Segregation Index ◽  
Coal Bottom Ash ◽  
Slump Flow ◽  
Fine Aggregates ◽  
The Stability

The influence of coal bottom ash on fresh properties of self-compacting concrete (SCC) were presented in this paper. Self-compacting concrete mixtures were produced by 0.40 water/powder ratio and coal bottom ash as a replacement of fine aggregates in varying percentages of 0%, 10%, 15%, 20%, 25% and 30%. The fresh concretes were tested for the key workability belongings of self-compacting concrete such as passing and filling abilities and segregation resistance. The fresh properties were investigated by slump flow; T500 spread time, sieve segregation and L-box test. It was found that the slump flow decreased whereas the T500 spread time increased with higher coal bottom ash content. The L-box blocking ratios changed from 0.92 to 0.65 and were mostly showed satisfactory blocking ratio. The presence of coal bottom ash improved the stability of SCC mixture and the segregation index obtained from sieve test reduced with greater bottom ash content. It can be concluding that the filling and passing ability of SCC decreased when the amount of coal bottom ash content increased. In addition, the segregation resistance index decreased with higher coal bottom ash content.

Experimental Study on the Workability of Self-Compacting Granite and Unwashed Gravel Concrete

2017 ◽  
Vol 31 ◽  
pp. 69-76
Author(s):  
Gideon O. Bamigboye ◽  
David O. Olukanni ◽  
Adeola A. Adedeji ◽  
Kayode J. Jolayemi
Keyword(s):  
Experimental Study ◽  
Coarse Aggregate ◽  
Mix Design ◽  
Fine Aggregate ◽  
Self Compacting Concrete ◽  
Consistency Test ◽  
Coarse Aggregates ◽  
Slump Flow ◽  
Filling Ability ◽  
Passing Ability

This study deals mainly with the mix proportions using granite and unwashed gravel as coarse aggregate for self-compacting concrete (SCC) and its workability, by considering the water absorption of unwashed gravel aggregate. Mix proportions for SCC were designed with constant cement and fine aggregate while coarse aggregates content of granite-unwashed gravel combination were varied in the proportion 100%, 90%/10%, 80%/20%, 70%/30%, 60%/40%, 50% /50%, represented by SCC1, SCC2, SCC3, SCC4, SCC5 and SCC6. 100% granite (SCC1) serves as the control. The workability of the samples was quantitatively evaluated by slump flow, T500, L-box, V- funnel and sieve segregation tests. Based on the experimental results, a detailed analysis was conducted. It was found that granite and unwashed gravel with SCC1, SCC2 and SCC3 according to EFNARC (2002) standard have good deformability, fluidity and filling ability, which all passed consistency test. SCC1, SCC2 and SCC3 have good passing ability while all mixes were in the limit prescribed by EFNARC (2002). It can be concluded that the mix design for varying granite-unwashed gravel combination for SCC presented in this study satisfy various requirements for workability hence, this can be adopted for practical concrete structures.

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 Compressive Strength by Incorporating Quarry Dust in Self-Compacting Concrete Grade M35

2018 ◽  
Vol 4 (4) ◽  
pp. 776 ◽  
Author(s):  
Mushtaq Ahmad ◽  
Sana Ullah ◽  
Aneel Manan ◽  
Temple Chimuanya Odimegeu ◽  
Salmia Beddu
Keyword(s):  
Compressive Strength ◽  
Strength Test ◽  
The Self ◽  
Kuala Lumpur ◽  
Self Compacting Concrete ◽  
Curing Period ◽  
Slump Flow ◽  
Compressive Strength Test ◽  
Super Plasticizer ◽  
Quarry Dust

The study has conducted to determine the workability and compressive strength of the self –compacting concrete. The sand has replaced with quarry dust with the proportion of 10, 20, 30 and 40% and super plasticizer was added 0.9%. The experiments were carried out at the Infrastructure University Kuala Lumpur (IUKL) concrete laboratory. Slump flow, J- Ring tests were carried out to determine the workability of self-compacting concrete and compressive strength test was conducted on 7 days and 28th days of curing period. A finding of the study shows that workability and compressive strength has increased by addition of quarry dust. It is concluded that addition of quarry dust up to 30%  improve the workability of the self-compacting concrete and further addition of quarry dust decrease the workability. Additionally, compressive strength of the quarry dust modified self-compacting concrete shows the trend of higher compressive strength up to 30% addition of quarry dust with sand replacement and further addition decrease the compressive strength.

Utilization of Iron Filings as Partial Replacements for Sand in Self-Compacting Concrete

2021 ◽  
Vol 47 (3) ◽  
pp. 906-916
Author(s):  
Simon O. Olawale ◽  
Mutiu A. Kareem ◽  
Habeeb T. Muritala ◽  
Abiola U. Adebanjo ◽  
Olusegun O. Alabi ◽  
...  
Keyword(s):  
Steel Production ◽  
Strength Properties ◽  
Self Compacting Concrete ◽  
River Sand ◽  
Slump Flow ◽  
Filling Ability ◽  
Fine Aggregates ◽  
Concrete Production ◽  
Fresh State ◽  
Passing Ability

The use of industrial by-products in concrete production is part of concerted efforts on the reduction of environmental hazards attributed to the mining of conventional aggregates. Consideration of iron filings (IF), a by-product from steel production process, is an environmentally friendly way of its disposal which is expected to yield economic concrete production. Six self-compacting concrete (SCC) mixes were made by partially substituting river sand with IF at 5%, 10%, 15%, and 20% and the mix without IF (0% IF) served as the control. The water-binder (w/b) ratio of 0.45 was adopted for all mixes. The fresh state properties of SCC evaluated include: filling ability determined using slump flow and T500 mm slump flow tests, passing ability determined using L-box test and segregation resistance determined using V-funnel tests. The strength properties of SCC considered were compressive and tensile strengths. All the SCC mixes met the fresh properties requirements for filling capacity, passing ability, and segregation resistance. The 28-day compressive and tensile strengths of SCC increased by 3.46% and 8.08%, respectively, with IF replacement up to 15% compared to the control SCC. However, there was reduction in compressive and tensile strengths of SCC with IF replacement beyond 15%. The strength properties of SCC is considerably enhanced with the addition of up to 15% IF. Hence, the optimum content of 15% IF is considered suitable as a replacement for river sand in SCC. Keywords: Self-compacting concrete; iron filings; fine aggregates; filling ability; passing ability

EFFECTS OF BAMBOO FIBERS AND LIMESTONE POWDER ON FRESH PROPERTIES OF SELF-COMPACTING CONCRETE

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Anthony Nkem Ede ◽  
Obatarhie Oshogbunu ◽  
Oluwarotimi Michael Olofinnade ◽  
Kayode Joshua Jolayemi ◽  
Solomon Olakunle Oyebisi ◽  
...  
Keyword(s):  
Coarse Aggregate ◽  
Particle System ◽  
Limestone Powder ◽  
Water Quantity ◽  
Cement Particle ◽  
Fresh Properties ◽  
Self Compacting Concrete ◽  
Slump Flow ◽  
Flow Test ◽  
Bamboo Fibers

Self-compacting concrete (SCC) flows through densely steel reinforced elements and consolidates under self-weight without need for vibration or compaction. This helps in complex and densely reinforced structures. The integration of fibers and fillers in concrete improves its general properties. The addition of fibers in particular can regulate the flow and workability of the concrete; hence, the high workable nature of SCC can be an ideal mix for the incorporation of fibers. This research investigates the effect of bamboo fibers and limestone powder on the fresh properties of self-compacting concrete. Bamboo fibers of an aspect ratio of 50 and varied volumes of 0.25%, 0.5%, 0.75% and 1% were adopted for this research. The workability of the mix was assessed by slump flow test and V-funnel test. For fiber volumes of 0.25%, 0.5%, 0.75%, it was observed that the coarse aggregate was evenly distributed across the spread, indicating good viscosity and stability of the mix. The presence of 10% percent limestone powder improved the workability of the concrete mix. This can be attributed to filler properties of limestone powder, which, affecting the cement particle system, changed the ordinary distance between them and modified the water quantity available for the hydration process. These results proved that the bamboo fiber and limestone powder can be sustainably adopted to regulate the flow-ability of SCC without compromising desired properties.

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