Lightweight Concrete Based on Gypseous Binding Materials, Modified with Microcrystalline Cellulose, and Cavitationly Processed Sawdust

2019 ◽  
Vol 945 ◽  
pp. 188-192 ◽  
Author(s):  
A.A. Pykin ◽  
E.Y. Gornostaeva ◽  
N.P. Lukutsova ◽  
J.S. Pykina
Keyword(s):  
Mechanical Properties ◽  
Microcrystalline Cellulose ◽  
Lightweight Concrete ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Water Soluble ◽  
Waste Wood ◽  
Matrix Microstructure ◽  
Calcium Sulfate Dihydrate ◽  
Reducing Substances

The physical and mechanical properties of lightweight constructional heat-insulating concrete (sawdust gypsum concrete) with high-strength gypsum binder, modified by food cotton microcrystalline cellulose and organic fillers of plant origin from the waste wood of coniferous and deciduous species in the form of cavitationly processed pine and birch sawdust have been studied. The dependence of the cavitation extraction time of water-soluble reducing substances (sugars) from sawdust on the strength of sawdust gypsum concrete is established. The changes in microstructure of the gypsum matrix, the mean density, bending tension strength and compression strength, the thermal conductivity coefficient of sawdust gypsum concrete on the basis of the cavitationly processed sawdust with the introduction of microcrystalline cellulose are analyzed. It is proven that microcrystalline cellulose compacts the space between the crystalline hydrates of calcium sulfate dihydrate in the gypsum matrix microstructure and improves the physical and mechanical properties of sawdust gypsum concrete.

scholarly journals Properties of High-Strength Flowable Mortar Reinforced with Palm Fibers

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Eethar Thanon Dawood ◽  
Mahyuddin Ramli
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Test Results ◽  
Palm Fiber ◽  
Toughness Index ◽  
Strength And Toughness

This study was conducted to determine some physical and mechanical properties of high-strength flowable mortar reinforced with different percentages of palm fiber (0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, and 1.6% as volumetric fractions). The density, compressive strength, flexural strength, and toughness index were tested to determine the mechanical properties of this mortar. Test results illustrate that the inclusion of this fiber reduces the density of mortar. The use of 0.6% of palm fiber increases the compressive strength and flexural strength by about 15.1%, and 16%, respectively; besides, the toughness index (I5) of the high-strength flowable mortar has been significantly enhanced by the use of 1% and more of palm fiber.

scholarly journals RESEARCH OF EFFECT OF DPEI-PROCESSING OF SHIITAKE FRUIT BODY ON PHYSICAL AND MECHANICAL PROPERTIES OF MUSHROOM SUSPENSION

2018 ◽  
Vol 41 (1) ◽  
pp. 27-33
Author(s):  
N.O. Sharkova ◽  
E.К. Zhukotskyi ◽  
Т.Y. Тurchyna ◽  
H.V. Dekusha ◽  
A.A. Makarenko
Keyword(s):  
Mechanical Properties ◽  
Dynamic Viscosity ◽  
Structural Characteristics ◽  
Specific Energy Consumption ◽  
Fruit Body ◽  
Heterogeneous Systems ◽  
Physical And Mechanical Properties ◽  
Water Soluble ◽  
Shiitake Mushroom ◽  
Working Bodies

The use of discrete-pulse energy input (DPEI) mechanisms in various industries has become a reliable tool for the intensification of heat and mass transfer processes in various technological lines and reduction of specific energy consumption. The study of structural transformations in heterogeneous systems under influence of mechanisms of DPEI opens up new possibilities for their use as evidenced by this article. Under certain conditions it is possible to prepare a mushroom suspension with specified characteristics for drying and enhance medicinal properties of the obtained powder product while retaining all valuable components of feedstock. The article presents the results of research of DPEI-processing effect of the shiitake mushroom fruit body on the on physical and mechanical properties and structural characteristics of the mushroom suspension. The influence of hydro module, temperature of the suspension and the layout of the working bodies of the rotor-pulse apparatus (RPA) on its dynamic viscosity was studied and the possibility of reducing viscosity by 2-3 times is shown.  An analysis of mushroom suspension microstructure has showed that with a certain layout of the working bodies of the RPA it is possible to control the degree of dispersion of particles and change the spatial structure of the aggregates in the volume of the dispersion medium. It is determined that self-organization of spatial aggregates from individual hyphae in such suspensions occurs over time. Moreover, the smaller the size of hyphae (≤ 25 microns after the RPA of the first version of the arrangement: rotor-stator-rotor) are, the larger the size of the spatial aggregates are formed. After the RPA with the second layout option, the fragments of hyphae had sizes ≥ 50 μm, but the dimensions of the spatial aggregates were three times smaller. It is found that after three times passing of the mushroom suspension through the RPA and its subsequent treatment in the cavitation device, the dynamic viscosity of the suspension is reduced by 20%. Confirmation of the the effectiveness of the DPEI-mechanisms in obtaining mushroom suspension is that due to the hydromechanical destruction of the polysaccharide structures of the chitin-glucan complex of the shiitake mushroom the content of the bioavailable complex of water-soluble oncostatic and immunoregulatory polysaccharides in the powder obtained by drying the mushroom suspension in an experimental spray dryer increased 6 times. References 13, figures 6.

scholarly journals Thermal Action on Normal and High Strength Cement Mortars

2020 ◽  
Vol 10 (18) ◽  
pp. 6455
Author(s):  
Marianela Ripani ◽  
Hernán Xargay ◽  
Ignacio Iriarte ◽  
Kevin Bernardo ◽  
Antonio Caggiano ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Peak Load ◽  
Physical And Mechanical Properties ◽  
Thermal Action ◽  
High Strength ◽  
Strength Loss ◽  
Brittle Behavior ◽  
Cement Mortars ◽  
Water Absorption Test

High temperature effect on cement-based composites, such as concrete or mortars, represents one of the most important damaging process that may drastically affect the mechanical and durability characteristics of structures. In this paper, the results of an experimental campaign on cement mortars submitted to high temperatures are reported and discussed. Particularly, two mixtures (i.e., Normal (MNS) and High Strength Mortar (MHS)) having different water-to-binder ratios were designed and evaluated in order to investigate the incidence of both the mortar composition and the effects of thermal treatments on their physical and mechanical properties. Mortar specimens were thermally treated in an electrical furnace, being submitted to the action of temperatures ranging from 100 to 600 °C. After that and for each mortar quality and considered temperature, including the room temperature case of 20 °C, water absorption was measured by following a capillary water absorption test. Furthermore, uniaxial compression, splitting tensile and three-points bending tests were performed under residual conditions. A comparative analysis of the progressive damage caused by temperature on physical and mechanical properties of the considered mortars types is presented. On one hand, increasing temperatures produced increasing water absorption coefficients, evidencing the effect of thermal damages which may cause an increase in the mortars accessible porosity. However, under these circumstances, the internal porosity structure of lower w/b ratio mixtures results much more thermally-damaged than those of MNS. On the other hand, strengths suffered a progressive degradation due to temperature rises. While at low to medium temperatures, strength loss resulted similar for both mortar types, at higher temperature, MNS presented a relatively greater strength loss than that of MHS. The action of temperature also caused in all cases a decrease of Young’s Modulus and an increase in the strain corresponding to peak load. However, MHS showed a much more brittle behavior in comparison with that of MNS, for all temperature cases. Finally, the obtained results demonstrated that mortar quality cannot be neglected when the action of temperature is considered, being the final material performance dependent on the physical properties which, in turn, mainly depend on the mixture proportioning.

MECHANICAL AND THERMAL PROPERTIES OF SAWDUST CONCRETE

2017 ◽  
Vol 79 (6) ◽  
Author(s):  
Ruhal Pervez Memon ◽  
Abdul Rahman Mohd. Sam ◽  
A. S. M. Abdul Awal ◽  
Lemar Achekzai
Keyword(s):  
Heat Transfer ◽  
Mechanical Properties ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Lightweight Concrete ◽  
Physical And Mechanical Properties ◽  
Developing Nations ◽  
Mechanical And Thermal Properties ◽  
Construction Technology ◽  
Long Duration

 Industrialization in developing countries has resulted in an increase in agricultural output and consequent accumulation of unmanageable agro wastes. Pollution arising from such wastes is a matter of concern for many developing nations. The aim of this study is to investigate the behavior of lightweight concrete and the utilization of sawdust as waste material in concrete. This paper focuses on the manufacturing of concrete which possess long duration heat transfer by using sawdust waste. In this research, cement to sawdust ratio of 1:1, 1:2 and 1:3 by volume was prepared for sawdust concrete, and the ratio of sand was kept constant that is 1. At these ratios, the mechanical and thermal properties like density, workability, strength and heat transfer were measured after, 7, 28 and 56 days of air curing. The tests results show that with the increase in the amount of sawdust, the workability, compressive strength, tensile strength and flexural strength decreased. It also resulted in reduction of heat transfer of sawdust concrete. Taking into account the overall physical and mechanical properties, sawdust concrete can be used in construction technology. 

scholarly journals THE DEPENDENCE OF THE PHYSICAL MECHANICAL PROPERTIES OF EXPANDED-CLAY LIGHTWEIGHT CONCRETE ON THE COMPOSITION

2010 ◽  
Vol 2 (6) ◽  
pp. 50-55
Author(s):  
Marija Vaičienė ◽  
Jurgita Malaiškienė
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Chemical Composition ◽  
Water Absorption ◽  
Lightweight Concrete ◽  
Physical And Mechanical Properties ◽  
Concrete Mixture ◽  
Active Filler ◽  
Binder Material ◽  
Substitute Materials

Binder material is the most expensive raw component of concrete; thus, scientists are looking for cheaper substitute materials. This paper shows that when manufacturing, a part of the binder material of expanded-clay lightweight concrete can be replaced with active filler. The conducted studies show that technogenic – catalyst waste could act as similar filler. The study also includes the dependence of the physical and mechanical properties of expanded-clay lightweight concrete on the concrete mixture and the chemical composition of the samples obtained. Different formation and composition mixtures of expanded-clay lightweight concrete were chosen to determine the properties of physical-mechanical properties such as density, water absorption and compressive strength.

Formation and properties of nanocomposites made up from solid aspen wood, melamine-urea-formaldehyde, and clay

Holzforschung ◽  
2007 ◽  
Vol 61 (2) ◽  
pp. 148-154 ◽  
Author(s):  
Xiaolin Cai ◽  
Bernard Riedl ◽  
S.Y. Zhang ◽  
Hui Wan
Keyword(s):  
Mechanical Properties ◽  
Ball Mill ◽  
Urea Formaldehyde ◽  
Surface Hardness ◽  
Physical And Mechanical Properties ◽  
Water Soluble ◽  
Aspen Wood ◽  
Wood Polymer ◽  
Density Surface

Abstract Wood polymer nanocomposites were prepared from solid aspen wood, water-soluble melamine-urea-formaldehyde (MUF) resin, and silicate nanoclays. The nanofillers were ground with a ball-mill before being mixed with the MUF resin and impregnated into the wood. The water-soluble prepolymer was mixed with the nanoclays at a mixing speed of 3050 rpm for 20 min to form impregnation solutions. Wood was impregnated with resin, which polymerized in situ under certain conditions. The physical and mechanical properties of the composite and the effect of ball-milling treatment of nanofillers on these properties were investigated. Significant improvements in physical and mechanical properties, such as density, surface hardness, and modulus of elasticity, were obtained for specimens impregnated with MUF resin and nanoclay-MUF resin mixtures. Ball-mill treatment favors dispersion of the nanofillers into the wood, but also appears to interfere with particle-resin adhesion.

Sign in / Sign up

Export Citation Format

Share Document