Characterization of building derived materials for partial replacement of pavement subgrade layer

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Ashok Kumar Suluguru ◽  
M. Jayatheja ◽  
Anasua GuhaRay ◽  
Arkamitra Kar ◽  
Anurag Anand
2020 ◽  
Vol 18 ◽  
pp. 100466
Author(s):  
R. Monge-Ortiz ◽  
S. Martínez-Llorens ◽  
M.J. Lemos-Neto ◽  
S.L. Falcó-Giaccaglia ◽  
M.J. Pagán ◽  
...  

2018 ◽  
Vol 149 ◽  
pp. 01058 ◽  
Author(s):  
M. Dahhou ◽  
R. Barbach ◽  
M. El Moussaouiti

Partial replacement of the Portland cement CPJ55 ingredients by various quantities of alumina sludge (AS), produced during drinking water plant sludge, was used in the preparation of mortar mold with dimensions 40×40×160 mm. The characterization of materials is carried out by X-ray fluorescence (XRF), Xray diffraction (XRD), free lime dosing, and the mechanical tests. Analysis of the chemical composition by XRF shows that the studied alumina sludge is mainly composed of aluminum oxide, silica, which is correlated with the principal mineral phases identified in the XRD analysis results. It is demonstrated that adding 5% of the alumina sludge in Portland cement does not affect the mineralogy of final product. Nevertheless, the compression and flexural strength tests (in 28 days) conducted on mortar sample comprising 5% sludge elucidate that it belongs to cement mortar class of type 32.5 R.


2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Cleidson Carneiro Guimarães ◽  
Samile Raiza Carvalho Matos

RESUMO: O presente trabalho tem como objetivo principal avaliar a influência da cinza da casca de coco verde (CCCV) nas propriedades das argamassas no estado fresco e endurecido, a partir da substituição parcial do cimento Portland (CP) por cinza. Esta proposta surge da problemática ligada à destinação da casca do coco como resíduo urbano e agroindustrial e dos impactos ambientais provocados pela produção do cimento Portland. Para realização dessa pesquisa foram produzidas uma argamassa de referência e outras três argamassas com diferentes teores de substituição do CP por CCCV. Inicialmente, foi feita a caracterização dos materiais utilizados no trabalho e a análise de índice de pozolanicidade da cinza. Em seguida, foram feitas análises referenciais das propriedades das argamassas produzidas no estado fresco e no estado endurecido. A partir das análises pode-se perceber que a presença da cinza na argamassa influencia na trabalhabilidade, resistência mecânica e na durabilidade da argamassa e que a CCCV não possui potencial pozolânico. A adição de até 10% de CCCV substituindo o cimento Portland é viável.
 
 ABSTRACT: This study aims to evaluate the influence of ash green coconut shell (AGCS) on the properties of mortars in fresh and hardened, from the partial replacement of Portland cement (PC) by gray. This proposal arises from problems linked to the allocation of coconut shell as urban and agro-industrial waste and environmental impacts caused by the production of Portland cement. For this survey were produced a reference mortar and three mortars with different CP replacement levels by AGCS. Initially, it was the characterization of the materials used at work and ash pozzolanicity index analysis. Next, analyzes were made reference the properties of mortars produced in fresh and hardened state. From the analysis it can be seen that the ash presence in the mortar influences the workability, strength and durability of the mortar and the CCCV not have pozzolanic potential. The addition of up to 10% AGCS replacing the Portland cement is feasible.


Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 992
Author(s):  
Andrijana Nedeljković ◽  
Marija Stojmenović ◽  
Jelena Gulicovski ◽  
Nenad Ristić ◽  
Sonja Milićević ◽  
...  

Numerous factors influence the complexity of environmental and waste management problems, and the most significant goal is the reuse of materials that have completed their “life cycle” and the reduction in the use of new resources. In order to reduce impact of waste slag on the environment, in the present study, waste slag, generated in heating plants after lignite combustion, was characterized in detail and tested for application as a replacement for cement in mortar or concrete production. For physical–chemical characterization of slag, different experimental and instrumental techniques were used such as chemical composition and determination of the content of heavy metals, investigation of morphological and textural properties, thermal analysis, X-ray, and infrared spectroscopy. Physical–mechanical characterization of slag was also performed and included determination of activity index, water requirement, setting time and soundness. A leaching test was also performed. Presented results show that waste slag may be used in mortar and concrete production as a partial cement replacement, but after additional combustion at 650 °C and partial replacement of slag with silica fume in the minimal amount of 12%. The maximal obtained cement replacement was 20% (17.8% slag and 2.2% of silica fume).


Agronomy ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1873
Author(s):  
Juliana França Lima ◽  
Maria Inês Dias ◽  
Carla Pereira ◽  
Marija Ivanov ◽  
Marina Soković ◽  
...  

Consumers have given preferences to food products that, in addition to the nutritional properties, also present bioactive characteristics with beneficial health effects. The use of Nonconventional Food Plants (NCFP) has been an asset for the food industry, not only due to its abundance but, also, because it does not compete with other vegetable matrices used for human consumption for its nutritional properties, chemical and bioactive potentiality. The present work aimed to study the granulometry and water absorption index of three seeds of unconventional food plants: niger, millet and birdseed, followed by their nutritional value, content in free sugars, fatty acids, organic acids, tocopherols and phenolic compounds by chromatographic methods and, also, the evaluation of the antioxidant, hepatotoxic and antimicrobial potential in their hydroethanolic extracts. Bakery products were developed with a partial replacement of wheat flour, using the centroid simplex method to understand the effect of applying NCFP flours in the final physical–chemical characteristics. The high granulometry associated with the high water absorption index indicates that the use of NCFP flours would have to be complemented with other flours for baking. The chemical composition of niger seed stood out the most; however, all seeds presented relatively low IC50 and MIC values for the inhibition of lipid peroxidation and antimicrobial activity, respectively. Finally, breads made with a mixture of millet and birdseed flour showed the greatest similarity to the control bread. Considering their composition in bioactive compounds, the use of these seeds is highly advisable in the context of a fortified diet, being sources of compounds of high nutritional value and with beneficial health effects for the final consumer.


2020 ◽  
Vol 9 (1) ◽  
pp. e56911597
Author(s):  
Pedro Valle Salles ◽  
Thiago Marques Viana ◽  
Camila Lacerda Gomes ◽  
Flávia Cristina Silveira Braga ◽  
Flávia Spitale Jacques Poggiali ◽  
...  

The construction industry is responsible for the generation of large volumes of waste, known as construction and demolition waste (CDW). Around the world, millions of tons of these wastes are generated annually, which often become important environmental liabilities. The situation gets worse as the sector develops. In Europe, only 15 of the 27 countries in the European Union annually produce around 180 million tonnes of CDW, in Brazil, the data about this indicates that in 2014 the municipalities collected about 45 million tons of CDW, quantity 4.1% higher than in 2013. In this scenario, the present study aims to evaluate the partial replacement of natural aggregates by CDW (aggregates of concrete waste) in the production of concretes. In this sense, the effects of this substitution on the workability and mechanical characteristics of the concretes produced, as well as the influence of the mixing method and the percentage of superplasticizer additive on the same characteristics were evaluated. The methodology basically consists in the production of seven different traits, which are references and different combinations of mixing method, aggregate substitutions and superplasticizer percentages. Specimens of these traces were molded for mechanical characterization. Workability parameters were also evaluated. It is concluded that the workability is strongly affected by the addition of CDW, but a good workability can be obtained with the use of superplasticizer additives. The mixing method did not change the results obtained for this property. The results also indicate that the compressive and tensile strengths are not negatively affected by the substitution of aggregates, as well as being not significantly affected by the presence of the percentages of superplasticizer used, nor by the mixing methods.


2020 ◽  
Vol 9 (11) ◽  
pp. e70291110468
Author(s):  
Maria José de Figueiredo ◽  
Anderson Ferreira Vilela ◽  
Celene Ribeiro Ataide ◽  
Rossana Maria Feitosa de Figueirêdo ◽  
Cristiani Viegas Brandão Grisi ◽  
...  

The objective of this work was to develop roll bread with partial replacement of wheat flour by malt bagasse (MB) and to evaluate the changes in their physical-chemical characteristics and microbiological parameters. Four formulations of breads were elaborated: one control without MB, and 3 formulations with partial replacement of wheat flour varying the MB amount in 5, 10 and 15%.  MB reduced the carbohydrate content of the dough; consequently, the calories of the bread rolls were also reduced. On the other hand, moisture, minerals and lipids contents were increased. The type of protein changed with the substitution of MB in the dough, but the amount of proteins was not altered. The lowest hardness values were observed in breads with 5% and 10% MB, being related to higher values of acidity in the dough. The increase in the mineral content of the dough was related to the darkening of the bread. All bread formulations showed microbiological quality within the limits established by Brazilian legislation for coliforms at 45 °C, Bacillus cereus and Salmonella sp. The formulation with 10% MB resulted in bread rolls with higher nutritional value, in terms of minerals, lower hardness and with a darker aspect all around when compared to the control bread, giving it an aspect of wholegrain bread.


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