The Effect of the Waste of Materials and Carbon Nanotube on the Concrete Incorporated with Steel Fibers

The addition of agricultural and industrial solid wastes and nanomaterials to concrete combined with steel fibers to improve the mechanical and electrical properties of concrete was investigated. This approach could be used in advanced applications in electromagnetic shielding and conductive concrete. Steel fibers were used at 2%wt. of sand and (induction furnace slag (EIF), carbon nanotube (CNT), steel wool fibers, prepared corn husks) at 0.5 and 1 wt.%. of cement. Obtained results of using 1% for both carbon nanotube and steel wool with steel fibers in the mixture 4 and 6, respectively, showed the highest rates of compressive strength. A similar result was shown when tested at 3,7 and 28 days of age and compressive strength was 47.4MPa,47.34MPa for the mixture 4 and 6 respectively. The electrical conductivity and electrical resistance of the samples were measured at the age of 7 days. The findings have also shown that adding steel wool as well as( CNT) gave the best results and the sample containing the furnace slag achieved satisfactory results as well.

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Environment-Friendly, Self-Sensing Concrete Blended with Byproduct Wastes

Sensors ◽

10.3390/s20071925 ◽

2020 ◽

Vol 20 (7) ◽

pp. 1925

Author(s):

Marat Konkanov ◽

Talal Salem ◽

Pengcheng Jiao ◽

Rimma Niyazbekova ◽

Nizar Lajnef

Keyword(s):

Electrical Properties ◽

Electrical Resistance ◽

Blast Furnace Slag ◽

Coal Fly Ash ◽

Environment Friendly ◽

Research Attention ◽

Mechanical And Electrical Properties ◽

Significant Research ◽

Parametric Studies ◽

Furnace Slag

Smart structures have attracted significant research attention in the last decade, mainly due to the capabilities of advanced concrete in electrical resistance-enabled self-sensing. In this study, we present a type of environment-friendly, self-sensing concrete enabled by electrical resistance. Environment-friendly, self-sensing concrete was casted with the additions of byproduct wastes (i.e., coal fly ash (FA), blast furnace slag (BOF) and red mud (RM)) at various volume fractions and cured using the conditions of 3, 7 and 28 days. The self-sensing concrete samples were experimentally tested to investigate the effects of the byproduct wastes on the mechanical and electrical properties (i.e., compressive strength and electrical resistance). In the end, parametric studies were experimentally conducted to investigate the influences of the byproduct wastes on the mechanical and electrical properties of the reported environment-friendly, self-sensing concrete.

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Static-Dynamic Properties of Reactive Powder Concrete with Blast Furnace Slag

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.82.100 ◽

2011 ◽

Vol 82 ◽

pp. 100-105 ◽

Cited By ~ 1

Author(s):

Huang Hsing Pan ◽

Jen Po Peng ◽

Yuh Shiou Tai ◽

Chao Shun Chang

Keyword(s):

Fracture Toughness ◽

Compressive Strength ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Applied Strain ◽

Steel Fibers ◽

Reactive Powder Concrete ◽

Applied Strain Rate ◽

Reactive Powder ◽

Furnace Slag

Reactive powder concrete (RPC) containing blast furnace slag prepared for hydraulic structure with a designed strength of 150 MPa is examined. We first investigate mixture proportions of RPC to fit the strength requirement, and then, concentrate on the material with 50% replacement of silica fume by blast furnace slag to study seismic resistant properties. Results indicate that curing process and steel fiber can enhance the compressive strength, flexural strength, shear strength and fracture toughness. With 210°C curing, flexural strength of RPC containing 2% steel fibers reaches 91 MPa, almost three times without the fibers. Meanwhile, the shear strength is 47.8 MPa. Dynamic stress-strain curves determined by SHPB test display that the compressive strength of RPC increases with increasing applied strain rate. Applied strain rate dominates the stress-strain behavior and fracture energy of RPC. Toughness index of RPC is improved powerfully by adding a few steel fibers. The fracture toughness of RPC with 50% slag replacement comes to 1.08 MPa·m1/2, and reaches 2.67 MPa·m1/2 as 2% steel fibers are added.

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The Effect of the Diameter of Carbon Nanotube on the Mechanical and Electrical Properties of Cement Mortar

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.730.479 ◽

2017 ◽

Vol 730 ◽

pp. 479-485 ◽

Cited By ~ 4

Author(s):

Yan Feng Wang ◽

Hui Hu ◽

Chui Qiang Rong

Keyword(s):

Carbon Nanotubes ◽

Compressive Strength ◽

Carbon Nanotube ◽

Electrical Properties ◽

Cement Mortar ◽

Multiwall Carbon Nanotubes ◽

Cement Matrix ◽

Sem Image ◽

Surrounding Matrix ◽

Mechanical And Electrical Properties

Two different diameter carbon nanotubes were incorporated into cement mortar to investigate the effect on mechanical and electrical properties of composites. Cement-based composites have been prepared from Portland cement with various amounts of multiwall carbon nanotubes (MWCNTS), ranging from 0% to 0.3% by cement weight. In this study, effective dispersion of two different diameter MWCNTS in water were achieved by applying ultrasonic energy and in combination with the use of a surfactant. The flexural and compressive strength of mixes were investigated at age 7 and 28 days. The conductivity of composites were conducted by the four probe method at age of 3 day, 7 day,14 day and 28 day. Results indicated that the two carbon nanotubes can improve the flexural and compressive strength of the composites. Furthermore, the well dispersion carbon nanotube solutions can decrease the resistance of the composites as the better conductive networks are formed in the cement matrix, especially at the later ages. Scanning electron microscopy observation used to observe the fracture surface of specimens containing 0% and 0.3wt% nanotubes indicated that the MWCNTS were well dispersed and there were no obvious agglomerates visible in the matrix. The SEM image revealed good bonding between the MWCNTS and the surrounding matrix.

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Mechanical and Durability Properties of Induction-Furnace-Slag-Incorporated Recycled Aggregate Concrete

Advances in Civil Engineering ◽

10.1155/2018/3297342 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Syed Ishtiaq Ahmad ◽

Md. Shafiqur Rahman

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Modulus Of Elasticity ◽

Induction Furnace ◽

Splitting Tensile Strength ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Aggregate Concrete ◽

Durability Properties ◽

Furnace Slag

Most of the steel mills in Bangladesh use induction furnace which produces large quantities of slags that have very little use except land filling. Therefore, feasibility of using this slag is examined in concrete with recycled aggregate, which is another waste product that is generated due to removal of old structures. Concrete with three target strengths, 17.23, 20.68, and 24.13 MPa, was prepared using recycled concrete acquired from a recently demolished building in Dhaka, Bangladesh. Recycled coarse aggregate was replaced with induction furnace slag by 0%, 25%, 50%, 75%, and 100% for each target strength. Samples prepared from these concretes were tested for workability, compressive strength, splitting tensile strength, modulus of elasticity, and durability properties e.g., porosity, absorption, and rapid chloride penetration. Review of test results suggests that workability of concrete was not adversely affected by incorporation of induction furnace slag. For up to 50% of induction furnace slag replacement, both compressive strength and splitting tensile strength increased in recycled aggregate concrete. Further, for all ratios of induction furnace slag replacement, modulus of elasticity increased compared to 100% recycled aggregate concrete. Porosity and absorption also decreased in concrete where up to 50% of recycled aggregate was replaced by induction furnace slag. Considering these, it is concluded that 50% of recycled aggregate can be replaced by induction furnace slag that will result in superior mechanical and durability properties in recycled aggregate concrete.

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Optimizing of the Cementitious Composite Matrix by Addition of Steel Wool Fibers (Chopped) Based on Physical and Mechanical Analysis

Materials ◽

10.3390/ma14051094 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1094

Author(s):

Akrm A. Rmdan Amer ◽

Mohd Mustafa Al Bakri Abdullah ◽

Yun Ming Liew ◽

Ikmal Hakem A. Aziz ◽

Jerzy J. Wysłocki ◽

...

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

High Strength ◽

Mechanical Analysis ◽

Primary Reinforcement ◽

Physicomechanical Properties ◽

Cementitious Composite ◽

Steel Wool ◽

Composite Matrix ◽

Wool Fibers

The demand for durable, resistant, and high-strength structural material has led to the use of fibers as reinforcing elements. This paper presents an investigation into the inclusion of chopped steel wool fibers (CSWFs) in cement to form a high-flexural strength cementitious composite matrix (CCM). CSWFs were used as the primary reinforcement in CCM at increments of 0.5 wt%, from 0.5–6 wt%, with ratios of cement to sand of 1:1.5 and water to cement of 0.45. The inclusion of CSWFs resulted in an excellent optimization of the physicomechanical properties of the CCM, such as its density (2.302 g/cm3), compressive strength (61.452 MPa), and maximum flexural strength (10.64 MPa), all of which exceeded the performances of other reinforcement elements reported in the literature.

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

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.2.2020.15.0527 ◽

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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The Influence of the Properties of the Material Used for Obtaining Geopolymers on Their Structure and Compressive Strength

Revista de Chimie ◽

10.37358/rc.17.6.5638 ◽

2017 ◽

Vol 68 (6) ◽

pp. 1182-1187

Author(s):

Ilenuta Severin ◽

Maria Vlad

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Wheat Straw ◽

Red Mud ◽

Blast Furnace Slag ◽

Complex Structure ◽

Point Of View ◽

Granulated Blast Furnace Slag ◽

Furnace Slag ◽

Straw Ash

This article presents the influence of the properties of the materials in the geopolymeric mixture, ground granulated blast furnace slag (GGBFS) + wheat straw ash (WSA) + uncalcined red mud (RMu), and ground granulated blast furnace slag + wheat straw ash + calcined red mud (RMc), over the microstructure and mechanical properties of the synthesised geopolymers. The activation solutions used were a NaOH solution with 8M concentration, and a solution realised from 50%wt NaOH and 50%wt Na2SiO3. The samples were analysed: from the microstructural point of view through SEM microscopy; the chemical composition was determined through EDX analysis; and the compressive strength tests was done for samples tested at 7 and 28 days, respectively. The SEM micrographies of the geopolymers have highlighted a complex structure and an variable compressive strength. Compressive strength varied from 24 MPa in the case of the same recipe obtained from 70% of GGBFS + 25% WSA +5% RMu, alkaline activated with NaOH 8M (7 days testing) to 85 MPa in the case of the recipe but replacing RMu with RMc with calcined red mud, alkaline activated with the 50%wt NaOH and 50%wt Na2SiO3 solution (28 days testing). This variation in the sense of the rise in compressive strength can be attributed to the difference in reactivity of the materials used in the recipes, the curing period, the geopolymers structure, and the presence of a lower or higher rate of pores, as well as the alkalinity and the nature of the activation solutions used.

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Waste-Based One-Part Alkali Activated Materials

Materials ◽

10.3390/ma14112911 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2911

Author(s):

Margarida Gonçalves ◽

Inês Silveirinha Vilarinho ◽

Marinélia Capela ◽

Ana Caetano ◽

Rui Miguel Novais ◽

...

Keyword(s):

Compressive Strength ◽

Microstructural Analysis ◽

Construction Materials ◽

Sodium Metasilicate ◽

High Compressive Strength ◽

Hardened State ◽

First Time ◽

Furnace Slag ◽

Alkali Activated

Ordinary Portland Cement is the most widely used binder in the construction sector; however, a very high carbon footprint is associated with its production process. Consequently, more sustainable alternative construction materials are being investigated, namely, one-part alkali activated materials (AAMs). In this work, waste-based one-part AAMs binders were developed using only a blast furnace slag, as the solid precursor, and sodium metasilicate, as the solid activator. For the first time, mortars in which the commercial sand was replaced by two exhausted sands from biomass boilers (CA and CT) were developed. Firstly, the characterization of the slag and sands (aggregates) was performed. After, the AAMs fresh and hardened state properties were evaluated, being the characterization complemented by FTIR and microstructural analysis. The binder and the mortars prepared with commercial sand presented high compressive strength values after 28 days of curing-56 MPa and 79 MPa, respectively. The mortars developed with exhausted sands exhibit outstanding compressive strength values, 86 and 70 MPa for CT and CA, respectively, and the other material’s properties were not affected. Consequently, this work proved that high compressive strength waste-based one-part AAMs mortars can be produced and that it is feasible to use another waste as aggregate in the mortar’s formulations: the exhausted sands from biomass boilers.

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