scholarly journals The Use of SEM and Other Complimentary Techniques for the Determination of Properties of Cementitious Materials

1992 ◽  
Vol 00 (8) ◽  
pp. 4-4 ◽  
Author(s):  
Eric A. Draper ◽  
Jan Skalny
Keyword(s):  
Building Materials ◽  
State Of The Art ◽  
Raw Materials ◽  
Cementitious Materials ◽  
Modern State ◽  
Microscopic Evaluation ◽  
The World ◽  
Cost Effect

The need for continued rehabilitation of our concrete infrastructure has lead to the adaptation of modern “state-of-the-art” analytical methods for the characterization of concrete and other cementitious materials. Some of these techniques have not, until relatively recently, been commonly associated with the evaluation of concrete but are very useful both as tools for quality assurance and in the determination of the extent of existing damage. The technique of interest here is the coordinated electron-optical microscopic evaluation of concrete.Concrete is the most widely used building material in the world. Contrary to popular belief, concrete is not inert but chemically very complex and dynamic. While it is true that, pound for pound, concrete and its raw materials (cement, aggregate and water} are the most inexpensive building materials available for construction, it is also true that it responds to its environment in numerous and sometimes very subtle ways. These responses may sometimes result in a loss of durability and tremendous amounts of time and money being expended while searching for the cause(s) of the problem and providing a cost-effect solution A quick survey of any large metropolitan area and the on-going construction repairs to highways and bridge decks there will quickly confirm this.

scholarly journals The Use of SEM and Other Complimentary Techniques for the Determination of Properties of Cementitious Materials

1992 ◽  
Vol 00 (8) ◽  
pp. 11-14
Author(s):  
Eric A. Draper ◽  
Jan Skalny
Keyword(s):  
Building Materials ◽  
State Of The Art ◽  
Raw Materials ◽  
Cementitious Materials ◽  
Modern State ◽  
Microscopic Evaluation ◽  
The World ◽  
Cost Effect

The need for continued rehabilitation of our concrete infrastructure has lead to the adaptation of modern “state-of-the-art” analytical methods for the characterization of concrete and other cementitious materials. Some of these techniques have not, until relatively recently, been commonly associated with the evaluation of concrete but are very useful both as tools for quality assurance and in the determination of the extent of existing damage. The technique of interest here is the coordinated electron-optical microscopic evaluation of concrete.Concrete is the most widely used building material in the world. Contrary to popular belief, concrete is not inert but chemically very complex and dynamic. While it is true that, pound far pound, concrete and its raw materials (cement, aggregate and water) are the most inexpensive building materials available for construction, it is also true that it responds to its environment in numerous and sometimes very subtle ways. These responses may sometimes result in a loss of durability and tremendous amounts of time and money being expended while searching far the cause(s) of the problem and providing a cost-effect solution. A quick survey of any large metropolitan area and the on-going construction repairs to highways and bridge decks there will quickly confirm this.

scholarly journals Effect of Cassava (Manihot esculenta Crantz: Euphorbiaceae) Starch on the Stabilization of Malagasy Lateritic Soil

2020 ◽  
Vol 2 (4) ◽  
pp. 467-481
Author(s):  
Harinivo Olsynthique Razanajatovo ◽  
Serge Ravelomanantsoa ◽  
Elise Octavie Rasoazanany ◽  
Aristote Matondo ◽  
Colette Masengo Ashande ◽  
...  
Keyword(s):  
Building Materials ◽  
Soil Stabilization ◽  
Raw Materials ◽  
Cassava Starch ◽  
Lateritic Soil ◽  
Manihot Esculenta Crantz ◽  
A Value ◽  
Physico Chemical

Laterite is one of the most widespread raw materials, especially in Madagascar. Its valorization as a building material would help to solve many socio-economic problems in Madagascar as well as in Africa. The use of this type of material fits well within the framework of high environmental quality, since the process uses an abundant material that does not require too much energy for its manufacture because it is dried in the open air. The aim of this work was to stabilize the laterite with cassava starch. The valorization of the latter would contribute to the development of new building materials. The study focuses on the mechanical characterization of specimens made with Vontovorona laterite in different proportions, which goes hand in hand with the determination of the physico-chemical parameters of the starch. To make specimens, we used techniques such as extraction, sieving, heating, laterite-stabilizing dosage, mixing, rotting, moulding, clamping, demoulding, drying. The results obtained show that the best stabilizing material is obtained if 15% of starch is mix to lateritic soil. The compressive strength in the dry state of the test specimens (samples) gave a significantly interesting result with a value of 54.8 bars (85% laterite with 15% starch). Thus the use of starch as a stabilizer in construction gave satisfactory results. This eco-friendly process, simple in its steps and practice, should be popularized among artisanal brick makers. Thus, replacing proportions of the Portland cement in soil stabilization with Cassava starch will reduce the overall environmental impact of the stabilization process. 

scholarly journals Thermal Characterization of Recycled Materials for Building Insulation

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3564
Author(s):  
Arnas Majumder ◽  
Laura Canale ◽  
Costantino Carlo Mastino ◽  
Antonio Pacitto ◽  
Andrea Frattolillo ◽  
...  
Keyword(s):  
Environmental Impact ◽  
Environmental Sustainability ◽  
Building Materials ◽  
Raw Materials ◽  
Natural Fibers ◽  
Thermal Characterization ◽  
Recycled Materials ◽  
Building Insulation ◽  
Operational Phase

The building sector is known to have a significant environmental impact, considering that it is the largest contributor to global greenhouse gas emissions of around 36% and is also responsible for about 40% of global energy consumption. Of this, about 50% takes place during the building operational phase, while around 10–20% is consumed in materials manufacturing, transport and building construction, maintenance, and demolition. Increasing the necessity of reducing the environmental impact of buildings has led to enhancing not only the thermal performances of building materials, but also the environmental sustainability of their production chains and waste prevention. As a consequence, novel thermo-insulating building materials or products have been developed by using both locally produced natural and waste/recycled materials that are able to provide good thermal performances while also having a lower environmental impact. In this context, the aim of this work is to provide a detailed analysis for the thermal characterization of recycled materials for building insulation. To this end, the thermal behavior of different materials representing industrial residual or wastes collected or recycled using Sardinian zero-km locally available raw materials was investigated, namely: (1) plasters with recycled materials; (2) plasters with natural fibers; and (3) building insulation materials with natural fibers. Results indicate that the investigated materials were able to improve not only the energy performances but also the environmental comfort in both new and in existing buildings. In particular, plasters and mortars with recycled materials and with natural fibers showed, respectively, values of thermal conductivity (at 20 °C) lower than 0.475 and 0.272 W/(m⋅K), while that of building materials with natural fibers was always lower than 0.162 W/(m⋅K) with lower values for compounds with recycled materials (0.107 W/(m⋅K)). Further developments are underway to analyze the mechanical properties of these materials.

scholarly journals The Influence of Cement Substitution by Biomass Fly Ash on the Polymer–Cement Composites Properties

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3079
Author(s):  
Beata Jaworska ◽  
Dominika Stańczak ◽  
Joanna Tarańska ◽  
Jerzy Jaworski
Keyword(s):  
Fly Ash ◽  
Building Materials ◽  
Raw Materials ◽  
Combustion Process ◽  
Biomass Combustion ◽  
Cement Composites ◽  
Cement Mortars ◽  
Mineral Additive ◽  
Biomass Fly Ash

The generation of energy for the needs of the population is currently a problem. In consideration of that, the biomass combustion process has started to be implemented as a new source of energy. The dynamic increase in the use of biomass for energy generation also resulted in the formation of waste in the form of fly ash. This paper presents an efficient way to manage this troublesome material in the polymer–cement composites (PCC), which have investigated to a lesser extent. The research outlined in this article consists of the characterization of biomass fly ash (BFA) as well as PCC containing this waste. The characteristics of PCC with BFA after 3, 7, 14, and 28 days of curing were analyzed. Our main findings are that biomass fly ash is suitable as a mineral additive in polymer–cement composites. The most interesting result is that the addition of biomass fly ash did not affect the rheological properties of the polymer–cement mortars, but it especially influenced its compressive strength. Most importantly, our findings can help prevent this byproduct from being placed in landfills, prevent the mining of new raw materials, and promote the manufacture of durable building materials.

scholarly journals THE FORMULATION OF DRY CURCUMA (CURCUMA XANTHORRHIZA ROXB.) EXTRACT MICROCAPSULES BY SPRAY WET MICROENCAPSULATION TECHNIQUES

2018 ◽  
Vol 11 (3) ◽  
pp. 226
Author(s):  
Samran Samran ◽  
Dalimunthe Dalimunthe ◽  
Dalimunthe Dalimunthe ◽  
Dalimunthe Dalimunthe
Keyword(s):  
Sodium Alginate ◽  
Brown Algae ◽  
Raw Materials ◽  
Light Exposure ◽  
Gastrointestinal Disease ◽  
Dry Weight ◽  
Compressibility Index ◽  
Curcuma Xanthorrhiza

 Objective: Curcuma xanthorrhiza Roxb. was used as hereditary medicinal plant for prevention of liver dysfunction, gastrointestinal disease, fever, and hemorrhoid. Curcuma extract was easy to damage because the light exposure, change of pH, weather and a long period of storage time. The problem can be solved by coating the extract with spray wet microencapsulation (SWM) technique. SWM technique is a method of preparing microcapsules in which a solution, suspension, or emulsion with a charged matrix is sprayed into opposing solution. The aim of this research was to formulate the dry Curcuma extract with SWM technique using sodium alginate as matrix.Methods: Brown algae (Sargassum ilicifolium) was a main resource of alginate acid. It was isolated using HCl 5% to make alginate acid and sodium alginate that was obtained by adding Na2CO3 5% to alginate acid solution. The microencapsulation process of Curcuma extract was done by SWM technique. The formula of Curcuma extract microencapsulation was design into three formulas: F1, F2, and F3. Microcapsules of Curcuma extract were being characterized for color intensity, analysis of scanning electron microscope (SEM), compressibility index, flowing time, and determination of angle repose.Results: The results showed that the higher concentration of sodium alginate used, the dry Curcuma extract microcapsules produced better. Particle size of extract microcapsules of Curcuma extract microcapsules SEM from F1, F2, F3 was 20 μm whereas dry weight of extracted microcapsule of Curcuma grows with increasing concentration of sodium alginate: F1 (0.2%) 19.86±0.11 g, F2 (0.4%) 20.66±0.73, F3 (0.6%) 21.29±0.64. The flowing time of F1, F2, and F3 was 6.92±0.56, 7.42±0.50, and 8.05±0.54 s consecutively.Conclusions: Based on the analysis of the study result, it can be concluded that the raw materials of Curcuma extract can be made by SWM technique using sodium alginate isolated from brown algae, and the characterization of dry Curcuma extract microcapsule of the three formulas met the requirements of the pre-formulation tests for capsule dosage form.

Preparation and Characterization of Paraffin/PMMA Core/Shell Structured Microcapsules

2011 ◽  
Vol 239-242 ◽  
pp. 524-527
Author(s):  
Su De Ma ◽  
Guo Lin Song ◽  
Zong Cheng Miao ◽  
Deng Wu Wang
Keyword(s):  
Building Materials ◽  
Raw Materials ◽  
Core Material ◽  
Synthesis Reaction ◽  
Key Factors ◽  
Thermal Reliability ◽  
Stabilizer Concentration ◽  
Accelerated Thermal Cycling ◽  
Change Material

Microencapsulated phase change material (MEPCM) was successfully prepared by using paraffin as the core material and PMMA as shell material. Both raw materials are innocuous, cheap and rich in resource. The influences of the key factors (i.e. emulsifier, stabilizer, concentration of the oil phase) on synthesis reaction were systematically evaluated. Conditions of synthesis reaction were also optimized. The relevant research results indicate that the prepared microcapsules are regular spheres with smooth and compact surface. The diameter of these spheres ranges from 1 to 2 mm. No obvious overcooling or overheating phenomena can be observed even when the content of paraffin of MEPCM reaches approximately 50 wt%. TGA analyses indicate that the heat resistance of the microcapsule increases by 10 °C compared to the pure paraffin. Accelerated thermal cycling tests also verify that the MEPCM displays good thermal reliability. The MEPCMs synthesized in the current study have potentials for thermal energy storage purposes such as PCM slurries, textiles and building materials.

scholarly journals NIRS Characterization of Paper Pulps to Predict Kappa Number

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Ana Moral ◽  
Elena Cabeza ◽  
Roberto Aguado ◽  
Antonio Tijero
Keyword(s):  
Near Infrared ◽  
Raw Materials ◽  
Analytical Techniques ◽  
Kappa Number ◽  
Point Of View ◽  
The World ◽  
Pulp Properties ◽  
Special Relevance

Rice is one of the most abundant food crops in the world and its straw stands as an important source of fibres both from an economic and an environmental point of view. Pulp characterization is of special relevance in works involving alternative raw materials, since pulp properties are closely linked to the quality of the final product. One of the analytical techniques that can be used in pulp characterization is near-infrared spectroscopy (NIRS). The use of NIRS has economic and technical advantages over conventional techniques. This paper aims to discuss the convenience of using NIRS to predict Kappa number in rice straw pulps produced under different conditions. We found that the resulting Kappa number can be acceptably estimated by NIRS, as the errors obtained with that method are similar to those found for other techniques.

scholarly journals Recycling building materials is the ideal way to protect the environment

2021 ◽  
Vol 258 ◽  
pp. 09046
Author(s):  
Arkadiy Larionov ◽  
Raheem Al-Rubaye Saba Jasim
Keyword(s):  
Environmental Pollution ◽  
Building Materials ◽  
Negative Impact ◽  
Raw Materials ◽  
Environmental Issues ◽  
Consumer Products ◽  
Energy Materials ◽  
Construction Waste ◽  
The World ◽  
The Ideal

Annotation. At the present time, the issues of combating environmental pollution are especially acute in the world. At various scientific and public platforms, the sources of the negative impact on the environment and ways to restore the ecosystem are discussed. The purpose of this article is to consider one of the main sources of environmental pollution - construction waste. Having studied a number of works on this topic and summarizing the results obtained, the authors give a detailed description of environmentally hazardous construction waste. At the same time, the authors propose a solution to this problem, which consists in the recycling of waste, that is, in the reuse of unnecessary things for the purpose of subsequent use as raw materials, energy, materials and consumer products. The authors argue that recycling waste can be safe and profitable, with great returns. Thus, the recycling of environmentally hazardous, in this particular case, construction waste will contribute not only to solving environmental issues, but also to improve the economic situation of the state.

Innovation of Building Materials: Ecological Bricks, Characterization of Complementary Inorganic Raw Materials

2019 ◽  
pp. 683-692
Author(s):  
Javier Flores-Badillo ◽  
Adriana Rojas-León ◽  
Alma Delia Román-Gutiérrez ◽  
Juan Hernández-Ávila ◽  
Eleazar Salinas-Rodríguez ◽  
...  
Keyword(s):  
Building Materials ◽  
Raw Materials
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