scholarly journals Development of Ecoefficient Engineered Cementitious Composites Using Supplementary Cementitious Materials as a Binder and Bottom Ash Aggregate as Fine Aggregate

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Jin Wook Bang ◽  
G. Ganesh Prabhu ◽  
Yong Il Jang ◽  
Yun Yong Kim
Keyword(s):  
Substitution Rate ◽  
Bottom Ash ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Cementitious Composites ◽  
Fine Aggregate ◽  
Test Results ◽  
Replacement Rate ◽  
Engineered Cementitious Composites ◽  
Advantageous Effect

The purpose of this study is to develop ecoefficient engineered cementitious composites (ECC) using supplementary cementitious materials (SCMs), including fly ash (FA) and blast furnace slag (SL) as a binder material. The cement content of the ECC mixtures was replaced by FA and SL with a replacement rate of 25%. In addition, the fine aggregate of the ECC was replaced by bottom ash aggregate (BA) with a substitution rate of 10%, 20%, and 30%. The influences of ecofriendly aggregates on fresh concrete properties and on mechanical properties were experimentally investigated. The test results revealed that the substitution of SCMs has an advantageous effect on fresh concrete’s properties; however, the increased water absorption and the irregular shape of the BA can potentially affect the fresh concrete’s properties. The substitution of FA and SL in ECC led to an increase in frictional bond at the interface between PVA fibers and matrix, improved the fiber dispersion, and showed a tensile strain capacity ranging from 3.3% to 3.5%. It is suggested that the combination of SCMs (12.5% FA and 12.5% SL) and the BA aggregate with the substitution rate of 10% can be effectively used in ECC preparation.

scholarly journals Performance of Eco Engineered Cementitious Composites Containing Supplementary Cementitious Materials as a Binder and Recycled Concrete Fines as Fine Aggregate

2021 ◽  
Vol 1200 (1) ◽  
pp. 012004
Author(s):  
M R Md Zain ◽  
C L Oh ◽  
L S Wee
Keyword(s):  
Tensile Strength ◽  
Fly Ash ◽  
Mechanical Performance ◽  
Cementitious Materials ◽  
Recycled Concrete ◽  
Supplementary Cementitious Materials ◽  
Partial Replacement ◽  
Cementitious Composites ◽  
Fine Aggregate ◽  
Engineered Cementitious Composites

Abstract Engineered cementitious composites (ECC) mixtures demand a large cement content, which is detrimental to their sustainable development because mass cement production is hazardous to the environment and human health. Thus, this paper investigates the mechanical performance of eco engineered cementitious composites (ECC) under axial compressive loading and direct tensile strength tests. The eco ECC used in this investigation was comprised of cement, superplasticizer, fly ash (FA) or ground granulated blast furnace slag (GGBS), polypropylene (PP) fibre, water and recycled concrete fines (RCF). Two (2) eco ECC mixture series were designed and prepared. GGBS70 (70 percent GGBS + 30 percent cement), FA70 (70 percent Fly Ash + 30 percent cement), GGBS80 (80 percent GGBS + 20 percent cement), and FA80 (80 percent Fly Ash + 20 percent cement) are the four Cement-GGBS and Cement-Fly Ash combinations examined in this study. Also every combination had two different RCF percentages, R0.2 (0.2 percent RCF) and R0.4 (0.4 percent RCF). The main objective of this research is to determine the optimum mix design for eco ECC that contains supplementary Cementitious Materials (SCMs) such as GGBS or FA. Additionally, recycled concrete fines (RCF) were used as a substitute for sand. The influence of different cement replacement materials and RCF content on compressive and tensile strength was experimentally investigated. The inclusion of GGBS as a partial replacement of cement in the eco concrete mixture results in greater compressive strength than Fly Ash (FA). The test results revealed that increasing the RCF content in the ECC mixture resulted in higher compressive and tensile strength. When the sand to binder ratio was adjusted between 0.2 and 0.4, the compressive and tensile strength of the ECC mixture increased.

scholarly journals Corrosion Behavior of AISI 1018 Carbon Steel in Localized Repairs of Mortars with Alkaline Cements and Engineered Cementitious Composites

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3327
Author(s):  
Erick Maldonado-Bandala ◽  
Noema Higueredo-Moctezuma ◽  
Demetrio Nieves-Mendoza ◽  
Citlalli Gaona-Tiburcio ◽  
Patricia Zambrano-Robledo ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Corrosion Behavior ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites ◽  
Cell Potential ◽  
Repair Mortar ◽  
Class F Fly Ash ◽  
Selection Of

The selection of materials for repairs of reinforced concrete structures is a serious concern. They are chosen for the mechanical capacity that the repair mortar achieves. However, several important characteristics have been left aside, such as the adhesion of the repair mortar with the concrete substrate, the electrical resistivity and—hugely important—the protection against corrosion that the repair material can provide to the reinforcing steel. The aim of this work was to study the corrosion behavior of AISI 1018 carbon steel (CS) in mortars manufactured with alkaline cements, engineered cementitious composites (ECC), and supplementary cementitious materials (SCM). Two types of ordinary Portland cement (OPC) 30R and 40R were used. The constituent materials for the mortars with ECC mixture mortars they use OPC 40R, class F fly ash (FA), silica fume (SF) and polypropylene (PP) fibers. The sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) were used as activating agents in alkali activated cements. The reinforced specimens were immersed in two different electrolytes, exposed to a 3.5 wt % of NaCl and Na2SO4 solutions, for 12 months and their electrochemical behavior was studied by half-cell potential (Ecorr) and linear polarization resistance (LPR) according to ASTM C876-15 and ASTM G59-97, respectively. The results obtained indicated that, the mortar they have the best performance and durability, is the conventional MCXF mortar, with OPC 30R and addition of 1% polypropylene PP fiber improves the behavior against the attack of chlorides and sulfates.

scholarly journals ESIGNING OF ALKALINE ACTIVATED CEMENTING MATRIX OF ENGINEERED CEMENTITIOUS COMPOSITES

2021 ◽  
Vol 2021 (2) ◽  
pp. 52-57
Author(s):  
Uliana Marushchak ◽  
◽  
Myroslav Sanytsky ◽  
Nazar Sydor ◽  
Ihor Margal ◽  
...  
Keyword(s):  
High Performance ◽  
Negative Impact ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Partial Replacement ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites ◽  
Specific Strength ◽  
Alkaline Activator ◽  
And Performance

The development of high-performance materials, which are characterized by high compressive and flexural strength, durability and performance properties, is an urgent problem of modern construction. Engineered cementitious composites are one such material. Improving of properties of composites is achieved by partial replacement of cement with supplementary cementitious materials. The ratio of binder and filler components and superplasticizer consumption were selected. The optimal ratio of cement:fly ash:sand is 1:1:1 and the dosage of polycarboxylate superplasticizer is 0.75% by weight of the binder. The reduction of the negative impact of the increased amount of fly ash, which is characterized by low reactivity, is provided by the introduction of metakaolin and alkaline hardening activator. Alkaline activated cement system is characterized by increasing of the early strength in 1.5 times comparison with equivalent mixture without alkaline activator. Strength of alkaline activated cementing matrix after 28 days is 66.1 MPa and specific strength Rc2/Rc28 is 0.61.

scholarly journals Utilization of tailings in cement and concrete: A review

2019 ◽  
Vol 26 (1) ◽  
pp. 449-464 ◽  
Author(s):  
Mifeng Gou ◽  
Longfei Zhou ◽  
Nathalene Wei Ying Then
Keyword(s):  
Compressive Strength ◽  
Cementitious Materials ◽  
Solid Wastes ◽  
Supplementary Cementitious Materials ◽  
Cement Clinker ◽  
Fine Aggregate ◽  
Granulated Blast Furnace Slag ◽  
Fine Aggregates ◽  
Compressive Strength Of Concrete ◽  
Cement And Concrete

AbstractOne of the advantages of cement and the cement concrete industry in sustainability is the ability to utilize large amounts of industrial solid wastes such as fly ash and ground granulated blast furnace slag. Tailings are solid wastes of the ore beneficiation process in the extractive industry and are available in huge amounts in some countries. This paper reviews the potential utilization of tailings as a replacement for fine aggregates, as supplementary cementitious materials (SCMs) in mortar or concrete, and in the production of cement clinker. It was shown in previous research that while tailings had been used as a replacement for both fine aggregate and cement, the workability of mortar or concrete reduced. Also, at a constant water to cement ratio, the compressive strength of concrete increased with the tailings as fine aggregate. However, the compressive strength of concrete decreased as the replacement content of the tailings as SCMs increased, even whentailings were ground into smaller particles. Not much research has been dedicated to the durability of concrete with tailings, but it is beneficial for heavy metals in tailings to stabilize/solidify in concrete. The clinker can be produced by using the tailings, even if the tailings have a low SiO2 content. As a result, the utilization of tailings in cement and concrete will be good for the environment both in the solid waste processing and virgin materials using in the construction industry.

scholarly journals Mechanical and Durability Properties of Concrete Made with Used Foundry Sand as Fine Aggregate

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
G. Ganesh Prabhu ◽  
Jin Wook Bang ◽  
Byung Jae Lee ◽  
Jung Hwan Hyun ◽  
Yun Yong Kim
Keyword(s):  
Substitution Rate ◽  
International Standards ◽  
Fine Aggregate ◽  
Test Results ◽  
Natural Sand ◽  
Foundry Sand ◽  
Durability Properties ◽  
Concrete Mixtures ◽  
Concrete Production ◽  
Strength And Durability

In recent years, the construction industry has been faced with a decline in the availability of natural sand due to the growth of the industry. On the other hand, the metal casting industries are being forced to find ways to safely dispose of waste foundry sand (FS). With the aim of resolving both of these issues, an investigation was carried out on the reuse of waste FS as an alternative material to natural sand in concrete production, satisfied with relevant international standards. The physical and chemical properties of the FS were addressed. The influence of FS on the behaviour of concrete was evaluated through strength and durability properties. The test results revealed that compared to the concrete mixtures with a substitution rate of 30%, the control mixture had a strength value that was only 6.3% higher, and this enhancement is not particularly high. In a similar manner, the durability properties of the concrete mixtures containing FS up to 30% were relatively close to those of control mixture. From the test results, it is suggested that FS with a substitution rate of up to 30% can be effectively used in concrete production without affecting the strength and durability properties of the concrete.

scholarly journals Static Hardness Testing of Cement Mortars Containing Different Types of Recycled Construction Waste Powders

Solids ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 331-340
Author(s):  
Zoltán Gyurkó ◽  
Rita Nemes
Keyword(s):  
Compressive Strength ◽  
Indentation Test ◽  
Hardness Test ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Test Results ◽  
Depth Sensing ◽  
Static Hardness ◽  
Cement Mortars ◽  
Aerated Concrete

The present paper deals with the hardness of cement mortars prepared with recycled materials that are potential supplementary cementitious materials (SCM). Two potential SCMs (aerated concrete powder (ACP) and concrete powder) were investigated and compared with a reference (neat cement) sample and a sample containing metakaolin (MK). The long-term performance of the mortars was studied up to the age of one year. Based on the compressive strength tests at different ages, neither concrete powder nor ACP significantly decreases the compressive strength at a 10% substitution ratio. The samples were studied with two types of static hardness tests: the Brinell hardness test and the depth sensing indentation test at two different load levels. The hardness test results indicated that the standard deviation of the results is lower at a higher load level. In the case of metakaolin and concrete powder, the change in the compressive strength was observable in the hardness test results. However, in case of the ACP, the compressive strength decreased, while the hardness increased, which can be traced back to the filler effect of aerated concrete powder. Finally, using the DSI test, the hardness results were analyzed on an energy basis. The analysis highlighted that the change in the hardness is connected to the elastic indentation energy, while it is independent from the dissipated (plastic) indentation energy.

scholarly journals Recycling of waste incineration bottom ash in the production of interlocking concrete bricks

2021 ◽  
Vol 15 (2) ◽  
pp. 101-112
Author(s):  
Nguyen Huu May ◽  
Huynh Trong Phuoc ◽  
Le Thanh Phieu ◽  
Ngo Van Anh ◽  
Chau Minh Khai ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Bending Strength ◽  
Bottom Ash ◽  
Waste Incineration ◽  
Engineering Properties ◽  
Fine Aggregate ◽  
Test Results ◽  
Toxic Material ◽  
Visible Defect

This study presents an experimental investigation on the recycling of waste incineration bottom ash (IBA) as a fine aggregate in the production of interlocking concrete bricks (ICB). Before being used, the concentration of heavy metal in IBA was determined to confirm it is a non-toxic material. In this study, the IBA was used to replace crushed sand (CSA) in the brick mixtures at different replacement levels of 0%, 25%, 50%, 75%, and 100% (by volume). The ICB samples were checked for dimensions, visible defects, compressive strength, bending strength, water absorption, and surface abrasion in accordance with the related Vietnamese standards. The test results demonstrated that the IBA used in this study was a non-toxic material, which can be widely used for construction activities. All of the ICB samples prepared for this study exhibited a nice shape with consistent dimensions and without any visible defects. The incorporation of IBA in the brick mixtures affected engineering properties of the ICB samples such as a reduction in the compressive strength and bending strength and an increment in water absorption and surface abrasion of the brick samples. As a result, the compressive strength, bending strength, water absorption, and surface abrasion values of ICB samples at 28 days were in the ranges of 20.6 – 34.9 MPa, 3.95 – 6.62 MPa, 3.8 – 7.2%, and 0.132 – 0.187 g/cm2, respectively. Therefore, either partial or full replacement of CSA by IBA, the ICB with grades of M200 – M300 could be produced with satisfying the TCVN 6476:1999 standard in terms of dimensions, visible defects, compressive strength, water absorption, and surface abrasion. These results demonstrated the high applicability of the local IBA in the production of the ICB for various construction application purposes. Keywords: interlocking concrete brick; waste incineration bottom ash; visible defect; compressive strength; bending strength; water absorption; surface abrasion.

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