Utilization of Brine Sludge in Nonstructural Building Components: A Sustainable Approach

The characterization and influence of brine sludge on the properties of cement-fly ash-sludge binders are presented. The reaction products formed during the hydration of binder provide an interlocking framework to physically encapsulate the waste particles and are responsible for the development of strength. The utilization of brine sludge in making paver blocks and bricks and the effect of sludge concentration on the engineering properties of these products are also discussed. These results clearly exhibited that brine sludge up to 35 and 25% can safely be utilized for making paver blocks and bricks, respectively. The leachability studies confirm that the metals ions and impurities in the sludge are substantially fixed in the matrix and do not readily leach from there. The utilization of brine sludge in construction materials could serve as an alternative solution to disposal and reduce pollution.

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Selection of Novel Geopolymeric Mortars for Sustainable Construction Applications Using Fuzzy Topsis Approach

Sustainability ◽

10.3390/su12155987 ◽

2020 ◽

Vol 12 (15) ◽

pp. 5987 ◽

Cited By ~ 1

Author(s):

Manfredi Saeli ◽

Rosa Micale ◽

Maria Paula Seabra ◽

João A. Labrincha ◽

Giada La Scalia

Keyword(s):

Fly Ash ◽

Construction Materials ◽

Fuzzy Topsis ◽

Industrial Wastes ◽

Engineering Properties ◽

Structural Element ◽

Structural Applications ◽

Multi Criteria Analysis ◽

Biomass Fly Ash ◽

Topsis Approach

Construction is recognized as one of the most polluting and energy consuming industries worldwide, especially in developing countries. Therefore, Research and Development (R&D) of novel manufacturing technologies and green construction materials is becoming extremely compelling. This study aims at evaluating the reuse of various wastes, originated in the Kraft pulp-paper industry, as raw materials in the manufacture of novel geopolymeric (GP) mortars whose properties fundamentally depend on the target application (e.g., insulating panel, partition wall, structural element, furnishing, etc.). Five different wastes were reused as filler: Two typologies of Biomass Fly Ash, calcareous sludge, grits, and dregs. The produced samples were characterized and a multi criteria analysis, able to take into account not only the engineering properties, but also the environmental and economic aspects, has been implemented. The criteria weights were evaluated using the Delphi methodology. The fuzzy Topsis approach has been used to consider the intrinsic uncertainty related to unconventional materials, as the produced GP-mortars. The computational analysis showed that adding the considered industrial wastes as filler is strongly recommended to improve the performance of materials intended for structural applications in construction. The results revealed that the formulations containing 5 wt.% of calcareous sludge, grits, and dregs and the one containing 7.5 wt.% of calcareous sludge, grits, dregs, and Biomass Fly Ash-1 have emerged as the best alternatives. Furthermore, it resulted that the Biomass Fly Ash-2 negatively influences the structural performance and relative rank of the material. Finally, this case study clearly shows that the fuzzy Topsis multi-criteria analysis represents a valuable and easy tool to investigate construction materials (either traditional and unconventional) when an intrinsic uncertainty is related to the measurement of the quantitative and qualitative characteristics.

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SUSTAINABILITY IMPLICATIONS OF THE USE OF HYBRID POLYVINYL ALCOHOL FIBRE-REINFORCED FERROCEMENT AND FLY ASH

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2018.130 ◽

2018 ◽

Vol 5 (2) ◽

Author(s):

Vanissorn Vimonsatit ◽

Wahidul K. Biswas

Keyword(s):

Fly Ash ◽

Polyvinyl Alcohol ◽

Sustainability Assessment ◽

Construction Materials ◽

Economic Benefits ◽

Engineering Properties ◽

Partial Replacement ◽

Bottom Line ◽

Polyvinyl Alcohol Fibre ◽

Alcohol Fibre

Extensive research has been conducted on the use of fly ash as a partial replacement of cement in order to promote the sustainable use of cement. Most of these research has focused on the investigation of the cementitious properties of the blended cement and the engineering properties of the end products, such as fly ash concrete. The sustainability benefit of using fly ash is often qualitatively perceived without any quantitative assessment. A recent study on the performance of hybrid polyvinyl alcohol fibre-reinforced ferrocement (HPVAF) shows that adding moderate amounts of fly ash in the mixes could maintain the ultimate flexure and tensile strength of HPVAF. The increased service life/durability and the use of FA up to a 25% replacement for cement in HPVAF not only conserve virgin resources for producing energy-intensive construction materials but also avoid associated environmental impacts due to the manufacturing of these materials. This certainly offers socio-economic benefits in terms of cost saving, enhance affordability and guaranteed material supply for the people both in current and future generations. Life cycle sustainability assessment (LCSA) was conducted to determine these triple bottom line benefits associated with the use of HPVAF and FA in building construction.

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Resistance of fly ash geopolymer binders to organic acids

Materials and Structures ◽

10.1617/s11527-020-01549-x ◽

2020 ◽

Vol 53 (5) ◽

Author(s):

Timothy A. Aiken ◽

Jacek Kwasny ◽

Wei Sha

Keyword(s):

Fly Ash ◽

Portland Cement ◽

Organic Acids ◽

Organic Acid ◽

Construction Materials ◽

Acid Resistance ◽

Calcium Content ◽

Reaction Products ◽

Acid Attack ◽

New Class

Abstract Fly ash geopolymers are a relatively new class of binders with the potential to reduce the CO2 emissions associated with Portland cement based construction materials. This paper reports on the organic acid resistance of fly ash geopolymers following exposure to acetic and lactic acid. Organic acids are prevalent in many circumstances including agriculture, production processes and waste management. These findings demonstrate that the surface of fly ash geopolymers had superior resistance to organic acids when compared with traditional Portland cement, evidenced by smaller mass losses. This was attributed to the formation of reaction products which were less susceptible to acid attack than those formed in Portland cement systems due to their lower calcium content. However, despite the surface of fly ash geopolymers appearing less deteriorated due to organic acid attack, they were found to have a higher porosity than their Portland cement counterparts making them more susceptible to acid ingress.

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Fly Ash/Blast Furnace Slag-Based Geopolymer as a Potential Binder for Mine Backfilling: Effect of Binder Type and Activator Concentration

Advances in Materials Science and Engineering ◽

10.1155/2019/2028109 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 15

Author(s):

Jingping Qiu ◽

Yingliang Zhao ◽

Jun Xing ◽

Xiaogang Sun

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

Setting Time ◽

Reaction Products ◽

Lower Reactivity ◽

The Matrix ◽

Binder Type ◽

Source Materials ◽

Furnace Slag

This article investigated the potential of fly ash (FA)/blast furnace slag- (BFS-) based geopolymer as a novel backfilling material. The effects of NaOH concentration and FA/BFS mass ratio were explored through XRD, FTIR, and TG-DTG analyses. The results indicated that the reaction products and strengths of geopolymer depended on the NaOH concentration and types of source materials. Slump, final setting time, and setting ratio increased as a function of FA content. However, the increase in FA content reduced the compressive strength and microstructure of the backfilling material (BM) due to the lower reactivity than BFS. Microstructure analysis reveals that the matrix tends to be denser with the BFS content and NaOH concentration increase.

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ELECTRICAL PROPERTIES OF FLY ASH GEOPOLYMER COMPOSITES WITH GRAPHITE CONDUCTIVE ADMIXTURES

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2019.22.0072 ◽

2019 ◽

Vol 22 ◽

pp. 72-76 ◽

Cited By ~ 2

Author(s):

Celílie Mizerová ◽

Ivo Kusák ◽

Pavel Rovnaník

Keyword(s):

Fly Ash ◽

Electrical Properties ◽

Health Monitoring ◽

Construction Materials ◽

Graphite Powder ◽

Traffic Monitoring ◽

The Matrix ◽

Matrix Resistance ◽

Alkali Activated ◽

Geopolymer Composites

Construction materials with increased electrical conductivity could be possibly used in health monitoring of structures (stress, deformation, damages), their maintenance or traffic monitoring. The aim of this study was the application of functional filler and its influence on the electrical properties of the alkali-activated fly ash matrix. The graphite powder was added to the reference material in the amount of 2–10 %. Besides the assessment of the critical amount of filler necessary to achieve a percolation threshold in the structure of the composite, the effect on the electrical properties of the matrix (resistance, capacitance, conductivity) was determined. The optimal amount of filler was also determined with respect to the changes in microstructure of the binder and its mechanical properties.

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Electrochemical Stability of Embedded Steel and Toxic Elements in Fly Ash/Cement Beds

MRS Proceedings ◽

10.1557/proc-86-59 ◽

1986 ◽

Vol 86 ◽

Cited By ~ 1

Author(s):

R. I. A. Malek ◽

D. M. Roy

Keyword(s):

Fly Ash ◽

Toxic Elements ◽

Construction Materials ◽

Leach Solution ◽

Electrochemical Stability ◽

Field Conditions ◽

Redox Potentials ◽

Electrochemical Stabilities ◽

The Matrix ◽

Regions Of Stability

ABSTRACTThe electrochemical stability in fly ash/cement beds is of major concern to the durability of construction metals (iron or steel) embedded in the matrix as well as the stabilization (fixation) of toxic elements. The electrochemical stabilities were evaluated by measuring the redox potential as a function of both time and leach solution. For simulating the field conditions, the measurements were made on leachates of a prepared solution simulating rain composition in the area of application and results were contrasted to those obtained on leachates of standard deionized water. Two leaching techniques were used: the standard EPA-EP test; a test developed at MRL/PSU for simulating field conditions in which leaching fluids are pumped up a fly ash/cement column. The redox potentials (based on hydrogen scale), Eh's, were plotted vs. pH of the leachates and the regions of stability of various construction materials and toxic elements were predicted. Tafel plots were also constructed for iron in contact with different leachates, and its corrosion rate was estimated.

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TEM characterization of reaction zone in a SiC fiber-reinforced titanium alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105758 ◽

1988 ◽

Vol 46 ◽

pp. 738-739

Author(s):

G. Das ◽

R. E. Omlor

Keyword(s):

Titanium Alloys ◽

Reaction Zone ◽

Carbon Layer ◽

Fiber Reinforced ◽

Reaction Products ◽

Sic Fibers ◽

Sic Fiber ◽

The Matrix ◽

Immense Potential

Fiber reinforced titanium alloys hold immense potential for applications in the aerospace industry. However, chemical reaction between the fibers and the titanium alloys at fabrication temperatures leads to the formation of brittle reaction products which limits their development. In the present study, coated SiC fibers have been used to evaluate the effects of surface coating on the reaction zone in the SiC/IMI829 system.IMI829 (Ti-5.5A1-3.5Sn-3.0Zr-0.3Mo-1Nb-0.3Si), a near alpha alloy, in the form of PREP powder (-35 mesh), was used a茸 the matrix. CVD grown AVCO SCS-6 SiC fibers were used as discontinuous reinforcements. These fibers of 142μm diameter contained an overlayer with high Si/C ratio on top of an amorphous carbon layer, the thickness of the coating being ∽ 1μm. SCS-6 fibers, broken into ∽ 2mm lengths, were mixed with IMI829 powder (representing < 0.1vol%) and the mixture was consolidated by HIP'ing at 871°C/0. 28GPa/4h.

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The Influence of Mixing Methods of Epoxy Composition Ingredients on Selected Mechanical Properties of Modified Epoxy Construction Materials

Materials ◽

10.3390/ma14020411 ◽

2021 ◽

Vol 14 (2) ◽

pp. 411

Author(s):

Izabela Miturska ◽

Anna Rudawska ◽

Miroslav Müller ◽

Monika Hromasová

Keyword(s):

Tensile Strength ◽

Epoxy Resin ◽

Construction Materials ◽

Preliminary Heating ◽

Epoxy Composition ◽

Mixing Speed ◽

Adhesive Composition ◽

Adhesive Compositions ◽

The Matrix ◽

Level Of Significance

The proper process of preparing an adhesive composition has a significant impact on the degree of dispersion of the composition ingredients in the matrix, as well as on the degree of aeration of the resulting composition, which in turn directly affects the strength and functional properties of the obtained adhesive compositions. The paper presents the results of tensile strength tests and SEM microphotographs of the adhesive composition of Epidian 57 epoxy resin with Z-1 curing agent, which was modified using three fillers NanoBent ZR2 montmorillonite, CaCO3 calcium carbonate and CWZ-22 active carbon. For comparison purposes, samples made of unmodified composition were also tested. The compositions were prepared with the use of six mixing methods, with variable parameters such as type of mixer arm, deaeration and epoxy resin temperature. Then, three mixing speeds were applied: 460, 1170 and 2500 rpm. The analyses of the obtained results showed that the most effective tensile results were obtained in the case of mixing with the use of a dispersing disc mixer with preliminary heating of the epoxy resin to 50 °C and deaeration of the composition during mixing. The highest tensile strength of adhesive compositions was obtained at the highest mixing speed; however, the best repeatability of the results was observed at 1170 rpm mixing speed. Based on a comparison test of average values, it was observed that, in case of modified compositions, the values of average tensile strength obtained at mixing speeds at 1170 and 2500 rpm do not differ significantly with the assumed level of significance α = 0.05.

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Hemp Fiber Reinforced Red Mud/Fly Ash Geopolymer Composite Materials: Effect of Fiber Content on Mechanical Strength

Materials ◽

10.3390/ma14030511 ◽

2021 ◽

Vol 14 (3) ◽

pp. 511 ◽

Cited By ~ 1

Author(s):

Eyerusalem A. Taye ◽

Judith A. Roether ◽

Dirk W. Schubert ◽

Daniel T. Redda ◽

Aldo R. Boccaccini

Keyword(s):

Fly Ash ◽

Mechanical Strength ◽

Red Mud ◽

Fiber Reinforced ◽

Brazilian Tensile Strength ◽

Hemp Fiber ◽

Hemp Fibers ◽

The Matrix ◽

Geopolymer Composites ◽

Scanning Electron

Novel hemp fiber reinforced geopolymer composites were fabricated. The matrix was a new geopolymer based on a mixture of red mud and fly ash. Chopped, randomly oriented hemp fibers were used as reinforcement. The mechanical properties of the geopolymer composite, such as diametral tensile (DTS) (or Brazilian tensile) strength and compressive strength (CS), were measured. The geopolymer composites reinforced with 9 vol.% and 3 vol.% hemp fiber yielded average DTS values of 5.5 MPa and average CS values of 40 MPa. Scanning electron microscopy (SEM) studies were carried out to evaluate the microstructure and fracture surfaces of the composites. The results indicated that the addition of hemp fiber is a promising approach to improve the mechanical strength as well as to modify the failure mechanism of the geopolymer, which changed from brittle to “pseudo-ductile”.

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