scholarly journals Artificial Thermal Decay: Influence of Mineralogy and Microstructure of Sandstone, Calcarenite and Marble

2021 ◽  
Vol 906 (1) ◽  
pp. 012123
Author(s):  
Andrea Aquino ◽  
Stefano Pagnotta ◽  
Marco Lezzerini
Keyword(s):  
Mechanical Properties ◽  
Thermal Stresses ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Thermal Decay ◽  
Ornamental Stone ◽  
Aesthetic Appearance ◽  
Ornamental Stones ◽  
Before And After ◽  
Volume Measurements

Abstract Within a major framework of studies around artificial weathering and its effects on different lithotypes, in this work we study the effects of thermal stresses after artificial thermal decay on different types of stones used in historical buildings: a sandstone, a calcarenite and a marble. The sandstone belongs to the so called “Macigno” Formation and mainly outcrops along the northern Apennine (North Western Tuscany) and it has been widely used around Tuscany for building purposes (e.g., in Florence, Lucca, Pisa, Pistoia, etc.); the analysed calcarenite (Gravina) comes from the surrounding of Matera Town and has been deeply used for the construction of the ancient buildings of the town itself; and the marble comes from the Carrara marble district (Northern Tuscany), a highly used stone throughout the centuries as ornamental stone. All these types of stone for their physical and mechanical properties, and aesthetic appearance, have been extensively used as both ornamental stones and as construction materials. To reproduce a plausible effect of natural thermal decay of the stones due to day-to-night and season-to-season fluctuations, we subjected the samples to artificial thermal decay. We carried out different thermal cycles on the samples by using a stove at 150°C and a muffle furnace at 300°C and 450°C. We analysed the physical and mechanical properties before and after each cycle to compare and evaluate the effects of thermal stresses on the stones. Among the different analyses: mass and volume measurements, water absorption tests, mercury intrusion porosimetry, thin-section observations and determination of chromatic alterations through image analysis and Munsell charts method. It was then possible to evaluate the influence of both mineralogy and microstructures on thermal decay of the studied stones (variations in fabric and modifications on physical and mechanical properties).

Frost Heaving Soil Road Use Synthetic Adhesive Reinforcement Method

2013 ◽  
Vol 740 ◽  
pp. 759-762
Author(s):  
Hao Zeng Bao
Keyword(s):  
Mechanical Properties ◽  
Industrial Waste ◽  
Construction Materials ◽  
Reference Value ◽  
Physical And Mechanical Properties ◽  
Road Construction ◽  
Experimental Methods ◽  
Frost Heaving ◽  
The World ◽  
Rock And Soil

In many areas, there are still a development road construction materials, traditionally, often use reinforced concrete, asphalt and other adhesive method to strengthen the low strength of rock and soil anti-freeze expansion coefficient; And now all countries in the world are studying how to use industrial production waste development of new composite materials. One of the most development potential, the production of industrial waste - slime. This paper USES the Russian kazan national construction university experimental methods, in the experiment to improve frost heaving soil physical and mechanical properties of the method for the synthesis of adhesive, based on the feasibility and applicability, environmental assessment of research and analysis, for the use of adhesive put forward a lot of reference value.

Influence of different concentrations of fibrinogen on the properties of a fibrin matrix for vascular tissue engineering

2021 ◽  
Vol 29 (1) ◽  
pp. 21-34
Author(s):  
Vera G. Matveeva ◽  
Mariam Yu. Khanova ◽  
Tatyana V. Glushkova ◽  
Larisa V. Antonova
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Metabolic Activity ◽  
Vascular Tissue ◽  
Physical And Mechanical Properties ◽  
Vascular Tissue Engineering ◽  
Test Machine ◽  
Fibrin Matrix ◽  
Before And After ◽  
The Difference

Aim. To evaluate the potential utility of fibrin matrices containing 10, 20, and 25 mg/ml of fibrinogen (fibrin-10, fibrin-20, and fibrin-30, respectively) in vascular tissue engineering (VTE). Materials and Methods. Fibrinogen was isolated using the method of ethanol cryoprecipitation and polymerized using a solution of thrombin and CaCl2. The fibrin structure was studied in a scanning electron microscope, and the physical and mechanical properties of the material were tested on a Zwick/Roell test machine. The metabolic activity of endothelial cells (EC) on the fibrin surface was evaluated by the MTT assay, and the viability of fibroblasts in the thickness of fibrin and possibility for migration by in fluorescent and light microscopy. Percent of fibrin shrinkage was determined from the difference in the sample volumes before and after removal of moisture. Results. The fiber diameter did not differ among all fibrin samples, but the pore diameter in fibrin-30 was smaller than those in fibrin-10 and fibrin-20. A possibility for migration of fibroblasts into the depth of the fibrin matrix and preservation of 97-100% viability of cells at a depth 5 mm was confirmed. The metabolic activity of EC on the surface of fibrin-20 and fibrin-30 exceeded that on collagen, fibronectin, and fibrin-10. All fibrin samples shrank in volume to 95.5-99.5%, and the highest shrinkage was seen in fibrin-10. The physical and mechanical properties of fibrin were inferior to those of human A. mammaria by a factor of 10. Conclusion. Fibrin with fibrinogen concentrations of 20 and 30 mg/ml maintains a high metabolic and proliferative activity of EC on the surface and also a high viability of fibroblasts in the matrix. Its availability, ease of preparation, and a number of other favorable properties make fibrin a promising material for VTE. However, the problem of insufficient strength requires further investigations.

Study of the Effect of PP and LDPE Thermoplastic Binder Addition on the Mechanical Properties and Physical Properties of Particulate Composites for Building Material Application

2019 ◽  
Vol 964 ◽  
pp. 115-123
Author(s):  
Sigit Tri Wicaksono ◽  
Hosta Ardhyananta ◽  
Amaliya Rasyida ◽  
Feisha Fadila Rifki
Keyword(s):  
Mechanical Properties ◽  
Compression Strength ◽  
Building Materials ◽  
Construction Material ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Waste Recycling ◽  
Plastic Waste ◽  
Particulate Composites ◽  
Water Absorbability

Plastic waste is majority an organic material that cannot easily decomposed by bacteria, so it needs to be recycled. One of the utilization of plastic waste recycling is become a mixture in the manufacture of building materials such as concrete, paving block, tiles, roof. This experiment purpose to find out the effect of addition of variation of LDPE and PP thermoplastic binder to physical and mechanical properties of LDPE/PP/Sand composite for construction material application. In this experiment are using many tests, such are SEM, FTIR, compression strength, density, water absorbability, and hardness. the result after the test are the best composition of composite PP/LDPE/sand is 70/0/30 because its have compression strength 14,2 MPa, while density value was 1.30 g/cm3, for the water absorbability is 0.073%, and for the highest hardness is 62.3 hardness of shore D. From the results obtained, composite material can be classified into construction materials for mortar application S type with average compression strength is 12.4 MPa.

High-Density Fiberboard from Wood and Keratin Fibers: Physical and Mechanical Properties

2021 ◽  
Vol 14 ◽  
Author(s):  
Menandro N. Acda
Keyword(s):  
Mechanical Properties ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
High Volume ◽  
High Density ◽  
Wood Fibers ◽  
Solid Waste Disposal ◽  
Renewable Materials ◽  
Polyurethane Resin ◽  
Keratin Fibers

Background: High-density fiberboards (HDF) are widely used as a substitute for solid wood in furniture, cabinet, construction materials, etc. Wood fibers are often used in the production of HDF but the use of renewable materials has gained worldwide interest brought about by global pressure to pursue sustainable development. An abundant source of renewable fibers that can be used to produce HDF is keratin from waste chicken feathers. The goal of the study is to investigate the use of keratin fibers in combination with wood fibers to produce HDF. No or limited studies have been conducted in this area and if successful, it could offer an alternative utilization for the billions of kilograms of waste feather produced by the poultry industry. HDF is a high volume feather utilization that can reduce pollution and help solve solid waste disposal problems in many countries. Methods: A series of dry-formed HDFs containing varying ratios of wood and keratin fibers bonded by polyurethane resin were produced. The physical and mechanical properties of the HDFs were determined. Results : The properties of the HDFs were affected by varying ratios of wood particles and keratin fibers. Dimensional stability as indicated by low levels of thickness swelling (<4.6%) and water absorption (<10%) was observed. Internal bond (2.47 MPa), MOE (5.8 GPa) and MOR (45 MPa) values were higher or comparable to those reported in the literature. Conclusion: HDF formed using a combination of wood and keratin fibers bonded together by polyurethane resin to as much as 50% keratin fibers were dimensionally stable with stiffness and strength above the minimum requirements for general use HDF as prescribed by EN 622-5.

Modeling of Building Materials as Complex Systems

2017 ◽  
Vol 730 ◽  
pp. 412-417 ◽  
Author(s):  
Irina Garkina ◽  
Alexander Danilov ◽  
Yuri Skachkov
Keyword(s):  
Mathematical Modeling ◽  
Complex System ◽  
Differential Equation ◽  
Mechanical Properties ◽  
Time Series ◽  
Building Materials ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Epoxy Composites ◽  
Damping Properties

We considered the problems of mathematical modeling of composite materials in the example of the development of materials for the protection against ionizing radiation. Construction materials are provided as a complex system with the appropriate attributes. The structure and physico-mechanical properties of the material were determined by the results of the modeling of kinetic processes. Process of forming properties is described by the differential equation in deviations from the equilibrium state (as for dispersion system). It is taken into account the elastic and damping properties of the material. To predict the behavior of the building material and the formation of his private mathematical models are used a representation of the processes as of time series. It is given the algorithm for studies (with considering prehistory) of formation of the basic physical and mechanical properties of epoxy composites for radiation protection. We present an example of the identification of building materials with special properties. Approaches used effectively in the development of materials with special properties.

Development of Fly Ash-Based Geopolymer Lightweight Bricks Using Foaming Agent - A Review

2015 ◽  
Vol 660 ◽  
pp. 9-16 ◽  
Author(s):  
Wan Mastura Wan Ibrahim ◽  
Kamarudin Hussin ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Aeslina Abdul Kadir ◽  
Mohammed Binhussain
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Building Material ◽  
Raw Materials ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Foaming Agent ◽  
Positive Effects ◽  
The World ◽  
Great Development

Bricks are widely used as a construction and building material due to its properties. Recent years have seen a great development in new types of inorganic cementitious binders called ‘‘geopolymeric cement’’ around the world. This prompted its use in bricks, which improves the greenness of ordinary bricks. The development of fly ash-based geopolymer lightweight bricks is relatively new in the field of construction materials. This paper reviews the uses of fly ash as a raw materials and addition of foaming agent to the geopolymeric mixture to produce lightweight bricks. The effects on their physical and mechanical properties have been discussed. Most manufactured bricks with incorporation of foaming agent have shown positive effects by producing lightweight bricks, increased porosity and improved the thermal conductivities of fly ash-based geopolymer bricks. However, less of performances in number of cases in terms of mechanical properties were also demonstrated.

scholarly journals A radiological study of some ornamental stones: the bluish granites from Extremadura (Spain)

2012 ◽  
Vol 12 (2) ◽  
pp. 395-401 ◽  
Author(s):  
D. Pereira ◽  
L. Neves ◽  
A. Pereira ◽  
M. Peinado ◽  
J. A. Blanco ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Physical And Mechanical Properties ◽  
Internal Exposure ◽  
Gamma Ray Spectrometry ◽  
Radon Emanation ◽  
Crushed Material ◽  
Ornamental Stone ◽  
Ornamental Stones ◽  
Representative Samples

Abstract. In the area of Trujillo (Extremadura, Spain) we have found a variety of striking bluish and secondary yellow granites outcropping within the Plasenzuela pluton. They are all quarried under different names and are characterized by leucocratic minerals in which a bluish phosphate is dispersed throughout the rock. Their physical and mechanical properties make these granites a perfect option for most applications as ornamental rocks. Within the pluton the radiological background is fairly homogeneous, with no significant differences between the gamma ray fluxes of the different facies. U (6.4 ± 0.51 ppm), Th (2.9 ± 0.47 ppm) and K2O (4.32 ± 0.26%) contents determined in the laboratory by gamma-ray spectrometry from representative samples are in good accordance with fast in situ measurements carried out with the same technique and also with conventional chemical analysis. Estimated activities for K-40, Ra-226 and Th-232 were, on average, 1022 ± 36 Bq kg−1, 84 ± 9 Bq kg−1 and 6.8 ± 1.6 Bq kg−1. On the basis of these results, the I index of EU technical document 112 was determined, with an average result of 0.66 ± 0.03. This suggests that the rock can be used with no restrictions for all types of construction purposes. Striking differences were observed between the blue facies and the yellow facies in radon exhalation tests from crushed material (0.03 Bq kg−1 vs. 0.20 Bq kg−1). Since both granites have similar uranium contents (6.3 ppm and 6.5 ppm, respectively), these results can probably be explained in terms of important differences in the mineralogical distribution of this chemical element, radon emanation being enhanced in the yellow facies. However, due to the ordinary use as ornamental stone, the yellow facies does not present a radiological risk in terms of excess effective dose due to internal exposure to radon.

Transmission electron microscopy of SI-AL-O-N alloys

1978 ◽  
Vol 36 (1) ◽  
pp. 302-303 ◽  
Author(s):  
M. Kirn ◽  
M. Rühle ◽  
H. Schmid ◽  
L.J. Gauckler
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Imaging Technique ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Operating Voltage ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

It is expected that Si-Al-O-N alloys are important high temperature construction materials. The phase diagrams for Si-Al-O-N alloys were studied systematically mainly by X-ray diffraction work (for a summary see). Different stable phases were found. For the understanding of the physical and mechanical properties it is of great interest to know for the different stable phases the microstructure and the morphology, which can be obtained by TEM observations. Results of some TEM studies are reported here utilizing not only the conventional TEM but also the lattice fringe imaging technique.Specimens of the different phases were produced as described in They were prepared for TEM observations. For high resolution work a Siemens ELMISKOP 102 (operating voltage 125 kV) was used fitted with a double tilting stage (± 45°), for conventional TEM studies the specimens were examined in an AEI EM7 high voltage EM operated at 1 MeV.

Study of the Aging of Cold-Cured SKU-PFL Type Polyurethane Filled with Waste Products

2021 ◽  
Vol 899 ◽  
pp. 119-124
Author(s):  
Tatyana R. Safiullina ◽  
Elvira N. Nurieva ◽  
Lyubov A. Zenitova
Keyword(s):  
Mechanical Properties ◽  
Silica Gel ◽  
Physical And Mechanical Properties ◽  
Climatic Conditions ◽  
Petrochemical Production ◽  
Waste Products ◽  
Material Quality ◽  
Before And After ◽  
Microsoft Office

The article describes the results of aging of samples of cold-cured molded polyurethanes of SKU-PFL brand filled with zeolite and silica gel - wastes of petrochemical production. The samples were aged under normal climatic conditions for 5 years. Filling of the samples varied from 10 to 50 %wt. Investigations of physical and mechanical properties of the samples before and after aging were carried out, the basic indicators of material quality were calculated using Microsoft Office Excel package. As a result of researches it was established that after aging the basic physical and mechanical properties of cast polyurethanes of SKU-PFL brand of cold curing filled with zeolite and silica gel change insignificantly, however the best resistance to aging are in samples with 20 %wt. zeolite and 10 %wt. silica gel filling both before and after aging that allowed to recommend them for long-term use of articles.

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