Thermal and Physico-Mechanical Characterization of Paraíba’s State Soils to Applying in Soil-Cement Bricks

Soils play a decisive role in the manufacture of building materials, especially, tiles and bricks. Production techniques cause negative impacts on the environment and add additional time to the production process. Three samples obtained from Paraíba State were characterized by thermal characterization, granulometric and physical-mechanical techniques. Thermal analysis was undertaken in two different atmospheres, at a flow rate of 110 ml/min and a heating rate of 10oC/min. Evaluation of the soils through their thermal characteristics for use in soil-cement bricks production is elucidated.

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Mechanical and thermal characterization of compact blocks made of clayey earth with wood ashes addition

MATEC Web of Conferences ◽

10.1051/matecconf/202030701030 ◽

2020 ◽

Vol 307 ◽

pp. 01030

Author(s):

Gbénondé Sèna Gladys Milohin ◽

Sènouhoua Victor Gbaguidi ◽

André Donnot ◽

Malahimi Anjorin ◽

Riad Benelmir

Keyword(s):

Building Materials ◽

Variable Mass ◽

Thermal Characteristics ◽

Thermal Characterization ◽

Mechanical Tests ◽

Thermal Tests ◽

Hot Strip ◽

Simple Compression ◽

French Association

The objective of this study is to evaluate the influence of wood ashes on the mechanical and thermal characteristics of the clayey earth-ashes compound (CEAC) compressed blocks. Variable mass percentages of 0% to 60% of wood ashes were incorporated to clayey earth stabilized with 10% of cement. The physical characteristics of the clayey earth were determined according to the protocols of the french association of normalization. The manufactured blocks were subjected to mechanical tests: simple compression and tensile by bending. The thermal conductivity was then appreciated by the method of the hot strip. The blocks made with a mixture of “90% clayey earth” and “10% cement”, usually used in construction in Benin, served as a reference material. From the results obtained, it appears that the clayey earth used is a soil A2ts: fine clayed sand in a very dry state. The results of the mechanical and thermal tests show that for an addition of wood ashes between 10% and 20% by weight, the performances of the blocks are significantly improved. The CEAC blocks formulated from 80% of the mixture “90% of clayey earth and 10% of cement” and 20% of wood ashes can be used as building materials.

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Thermal Characterization of Recycled Materials for Building Insulation

Energies ◽

10.3390/en14123564 ◽

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.

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Impact of spineless cactus cultivation (O. Ficus-indica) on the thermal characteristics of soil

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2148 ◽

2018 ◽

Vol 13 (1) ◽

pp. 1

Author(s):

Willames De Albuquerque Soares

Keyword(s):

Heat Capacity ◽

Thermal Characteristics ◽

Thermal Characterization ◽

Biological Processes ◽

Volumetric Heat Capacity ◽

Average Value ◽

Brazilian Semiarid ◽

Cultivation Techniques ◽

Soil Changes

Temperature is a fundamentally important factor for understanding the physical, chemical, and biological processes that occur in soil. However, there are few studies in the Brazilian semiarid zone that seek to understand how soil degradation affects its thermal characteristics. The objective of this study was to evaluate the influence of cultivation techniques on the thermal characterization of soil, using the model proposed by Johansen. The study was conducted in the Agreste region of the state of Pernambuco, Brazil on two plots of land, one with native vegetation (Caatinga) and the other with spineless cactus (O. ficus - indica). It was observed that the procedures used to prepare the soil for cultivation of spineless cactus caused a reduction in the capacity to transmit the surface temperature to the interior of the soil. Changes in the physical properties of the soil required for cultivation resulted in a reduction in the average value of the volumetric heat capacity of about 22%; an increase of approximately 5% in the average volumetric heat capacity and a 26% increase in the thermal diffusivity of the soil, as well as a reduction of approximately 50% in the heat flux from the surface of the soil.

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Thermal Characterization of Non-Isolated DC to DC Convertor

ASME 2011 Pacific Rim Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Systems, MEMS and NEMS: Volume 2 ◽

10.1115/ipack2011-52121 ◽

2011 ◽

Author(s):

Shiladitya Chakravorty ◽

Bahgat Sammakia ◽

Varaprasad Calmidi

Keyword(s):

Power Dissipation ◽

High Performance ◽

Field Effect Transistors ◽

Thermal Characteristics ◽

Thermal Characterization ◽

Input Voltage ◽

Thermal Design ◽

Power Module ◽

Improved Performance

Improved performance of semiconductor devices in recent years has resulted in consequent increase in power dissipation. Hence thermal characterization of components becomes important from an overall thermal design perspective of the system. This study looks at a high performance non-isolated point of load power module (a DC to DC converter) meant for advanced computing and server applications. Thermal characteristics of the module were experimentally analyzed by placing the power module on a bare test board (with no insulation) inside a wind tunnel with thermocouples attached to it. There were three devices on this module that dissipate power. There were two FETs (Field Effect Transistors) and an inductor which can be considered as sources. The consolidated power dissipation from the module was calculated by measuring the input voltage and input current while keeping the output voltage and current constant. Temperatures at various points on the module and the test card were recorded for different air flow velocities and overall power dissipation. Subsequently this set up was numerically analyzed using a commercially available computational fluid dynamics (CFD) code with the objective of comparing the results with experimental data previously obtained.

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Study of a Typical Soil Used for Concrete Bricks in Miracema, State of Rio de Janeiro, Brazil

Materials Science Forum ◽

10.4028/www.scientific.net/msf.820.40 ◽

2015 ◽

Vol 820 ◽

pp. 40-45

Author(s):

Niander Aguiar Cerqueira ◽

Jonas Alexandre ◽

Afonso Rangel Garcez de Azevedo ◽

Gustavo de Castro Xavier ◽

Veronica Scarpini Candido ◽

...

Keyword(s):

Urban Areas ◽

Rio De Janeiro ◽

Building Materials ◽

Particle Density ◽

Sustainable Solutions ◽

Soil Cement ◽

Local Soil ◽

Concrete Blocks ◽

Typical Soil

The use of natural resources for sustainable development is becoming a relevant issue in modern societies. In particular, building materials composed of local soil or available residues are considered sustainable solutions for housing construction in relatively small urban areas. In the present work a preliminary study was conducted on a typical soil in the municipal area of Miracema, state of Rio de Janeiro, Brazil. The study comprised the characterization of the particle size distribution and particle density of the soil. In addition, the application of the soil by combining with Portland cement was investigated to produce concrete blocks specified as soil-cement bricks by the Brazilian norm. The results indicated that a trace of 14 parts of soil, 6 parts of local gravel and 4 parts of cement/water produced concrete blocks that comply with the compression strength specified by the norm.

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Thermal Characterization of Bacterial Cellulose/Polyvinyl Alcohol Nanocomposite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1123.303 ◽

2015 ◽

Vol 1123 ◽

pp. 303-307 ◽

Cited By ~ 3

Author(s):

Akhmad Zainal Abidin ◽

Hafis Pratama Rendra Graha

Keyword(s):

Bacterial Cellulose ◽

Melting Temperature ◽

Healing Process ◽

Thermal Characteristics ◽

Cost Effective ◽

Thermal Characterization ◽

Fermentation Medium ◽

Scanning Calorimetry ◽

Regeneration Rate

Bacterial cellulose (BC) is a natural polymer which can be produced from various substrates easily found in Indonesia. Bacterial cellulose is believed to be a promising and cost effective bone scaffold in which a bone regeneration rate enhanced so the healing process is faster. In this experiment, Bacterial Cellulose (BC)/ Polyvin y l Alcohol (PVA) nanocomposite was made to give a further improvement in the properties. This nanocomposite was made thorough BC biosynthesis in Gluconacetobacter xylinus fermentation medium that was modified by addition of PVA. The PVA concentrations were varied as 0, 3, 6, 9, and 12 % w of fermentation medium. The culture had been agitated by magnetic stirrer for 28 days before freeze drying method was conducted to obtain dry BC/PVA nanocomposite. The product of BC/PVA nanocomposite was then studied for thermal characteristics using Differential Scanning Calorimetry (DSC) and Thermogravimetry Analysis (TGA). Pure BC has melting temperature (Tm) at 350 . 3oC and pure PVA at 181 . 3oC. Experimental results showed that the higher PVA content in fermentation medium decreased the melting temperature of BC/PVA nanocomposite produced.

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