Modified Composition for Fixing Sandy Soils

2020 ◽  
Vol 992 ◽  
pp. 143-148
Author(s):  
Irina V. Kozlova ◽  
Alexey E. Bespalov ◽  
Olga V. Zemskova
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Concrete Structure ◽  
Structural Characteristics ◽  
Control Sample ◽  
Sandy Soils ◽  
Nucleation And Growth ◽  
Landscape Design ◽  
Directional Crystallization ◽  
Hardening System

The possibility of using a modified composition based on slag Portland cement with the addition of stabilized finely dispersed slag in geotechnical construction and in landscape design is considered. The physical, mechanical and structural characteristics of samples hardening in normal conditions and under the influence of aggressive media were studied. It is established that the compressive and flexural strength of the modified samples is higher than that of the control sample. When hardening in normal conditions, on the first day, the flexural strength of modified specimens increased by 59%, at the grade age by 51%, compressive strength - 2.3 times and by 83%, respectively. When hardening in aggressive media, an increase in the strength of the modified specimens is also observed (flexural by 35–58%, compressive by 7–15%). This is explained by the fact that stabilized slag particles in a hardening system perform two functions: they are centers of directional crystallization for nucleation and growth of newgrowths, and full participants in the hydration process, binding calcium hydroxide to crystallohydrate compounds, thereby preventing the formation of ettringite when the concrete structure is exposed to aggressive media.

scholarly journals Experimental Study on Influence of Methylcellulose on Tensile and Flexural Strength of Normal Strength Ordinary Portland Cement Concrete

2021 ◽  
Vol 40 (4) ◽  
pp. 703-713
Author(s):  
Ali Ahmed ◽  
Shakir Ahmad ◽  
Muhammad Mannal Kaleem ◽  
Muhammad Bilal Zahid
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Control Sample ◽  
Modulus Of Rupture ◽  
Compression Tests ◽  
Portland Cement Concrete ◽  
Concrete Cylinder ◽  
Compressive Strength Of Concrete ◽  
Normal Strength

Current study explores the possibility of improvement in various categories of concrete’s strengths (including tensile strength, flexural strength etc.) by using methylcellulose as an additive. The effect of methylcellulose on concrete’s compressive strength has also been investigated experimentally. Concrete samples were casted with several methylcellulose to binder ratios varying from 0.002 to 0.01 by weight of cement. Several tests were performed on concrete specimens including concrete cylinder and cube compression tests, split cylinder tests and modulus of rupture tests. Results showed that addition of methylcellulose increased the tensile strength of concrete. Addition of 0.2% of methylcellulose increased the tensile strength of concrete by 16%. This increase in tensile strength reached up to 73% of the control sample on addition of 1% methylcellulose. It was observed that the effect of methylcellulose on compressive strength of concrete depends upon the type of samples being tested (cube or cylinder). The compressive strength of concrete cylinders showed a plateau behavior with peak at 0.4% methylcellulose content with an increase of 18.7%. Effect of methylcellulose on concrete cylinder strength becomes insignificant beyond 0.6%. It was observed that addition of methylcellulose reduces the modulus of rupture values. The reduction in MOR was only 3% at 0.2% methylcellulose content but it grew to 30% at 1% methylcellulose content. The research presents an effective way of increasing tensile strength of concrete but without significant effect on concrete’s compressive strength and modulus of rupture values. These findings can be used to determine optimum content of methylcellulose to achieve desired performance from concrete depending upon the intended use.

scholarly journals Influence of Fibre Length on the Behaviour of Polypropylene Fibre Reinforced Cement Concrete

2018 ◽  
Vol 4 (9) ◽  
pp. 2124-2131 ◽  
Author(s):  
Imtiaz Ahmed Memon ◽  
Ashfaque Ahmed Jhatial ◽  
Samiullah Sohu ◽  
Muhammad Tahir Lakhiar ◽  
Zahid Hussain Khaskheli
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Control Sample ◽  
Fibre Length ◽  
Reinforce Concrete ◽  
Polypropylene Fibre ◽  
Cement Concrete ◽  
Reinforced Cement ◽  
Increased Strength ◽  
Vast Range

Concrete being a mixture of cement, aggregates (fine and coarse) and water, can be used in vast range of applications. It has excellent durability and availability which are its main advantages. Though, concrete is strong in compression it is comparatively weak in tensile loading. Over the years various materials have been used to reinforce concrete to withstand the tensile stresses. Polypropylene fibre is one such fibre which comes in varied sizes, is nowadays being utilized to reinforce concrete. In this study, three PP fibres were used at 0.20%, 0.25% and 0.30% content by weight. The flexural and compressive strengths were determined. Based on the results, it was observed with increase in size of fibre the compressive strength decreased significantly though it was still higher than the controlled sample. The length of PP fibres had significant effect on the compressive strength and flexural strength of concrete. Short PP fibres showed relatively higher compressive strength but lower flexural strength when higher fibre content is used, while long PP fibres achieved lower compressive strength but higher flexural strength than shorter PP fibres. The optimum dosage for both PP fibre sizes was 0.25% at which it achieved increased strength as compared to control sample.

STUDYING THE STABILITY OF AQUEOUS SUSPENSIONS OF MULTIWALLED CARBON NANOTUBES USED FOR THE MODIFICATION OF COMPOSITE MATERIALS

2014 ◽  
Vol 6 (2) ◽  
pp. 62-68
Author(s):  
Alena Politaeva ◽  
Grigory Yakovlev ◽  
Damir Khazeev
Keyword(s):  
Carbon Nanotubes ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Multiwalled Carbon Nanotubes ◽  
Control Sample ◽  
Multiwalled Carbon ◽  
Aqueous Suspensions ◽  
Chemical Studies ◽  
The Stability ◽  
Physical And Chemical

In this paper, the stability of aqueous suspensions of multiwalled carbon nanotubes (MWCNTs) has been studied with physical and chemical methods. The optimum dispersion time of MWCNT suspension in a rotary homogenizer has been found. The dispersion time being increased, the quality of the suspension decreases. The data of the physical and chemical studies has also been confirmed experimentally on gypsum samples. The samples modified with MWCNT suspension of 2-hour dispersion show an increase in flexural strength and compressive strength by 40% and 48%, respectively, in comparison with the control sample, whereas the samples modified with MWCNT suspension of 10-hour dispersion show a decrease in flexural strength and compressive strength. The microstructure of the gypsum samples was studied with a scanning electron microscope.

scholarly journals Mechanical properties of resin composites containing bioactive glass and experimental nano zinc-silica complex

2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 137-142
Author(s):  
Mehmet Gökberkkaan Demirel ◽  
Makbule Tuğba Tunçdemir
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Bioactive Glass ◽  
Resin Composite ◽  
Testing Machine ◽  
Control Sample ◽  
Dental Composite ◽  
Resin Composites ◽  
Nano Zinc

Aim: Secondary caries is an important problem in dental composite restoration, and nanoparticles are commonly added to the structures of resin composites to improve their antimicrobial properties. The aim of this study is to evaluate the mechanical properties of composite materials containing bioactive glass (BAG) and an experimental nano zinc-silica (NZS) complex. Methodology: An experimental resin composite containing 70 wt% filler was produced and used as a control sample. This experimental resin composite was then modified by adding different amounts of BAG (10%), NZS (10%), and both BAG and NZS (10% + 10%). NZS was synthesized in situ by milling zinc and silica to nanoscale level. Compressive strength and flexural strength were investigated using a universal testing machine. Data were analyzed using one-way ANOVA and the Tukey post-hoc test. Results: There were no statistically significant differences in compressive strength caused by the filler amount, but statistically significant changes were found in flexural strength. Although the addition of antimicrobial agents to resin composites reduces their physical properties, this is not a clinically unacceptable limit. Conclusion: NZS exhibits better mechanical properties than does BAG, but both materials can be used safely in restorative materials.   How to cite this article: Tunçdemir MT, Demirel MG. Mechanical properties of resin composites containing bioactive glass and experimental nano zinc-silica complex. Int Dent Res 2021;11(Suppl.1):137-42. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.21   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.  

scholarly journals Preparation of Electric- and Magnetic-Activated Water and Its Influence on the Workability and Mechanical Properties of Cement Mortar

2021 ◽  
Vol 13 (8) ◽  
pp. 4546
Author(s):  
Kaiyue Zhao ◽  
Peng Zhang ◽  
Bing Wang ◽  
Yupeng Tian ◽  
Shanbin Xue ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Cement Paste ◽  
Cement Mortar ◽  
Environmental Issues ◽  
Chemical Admixtures ◽  
Untreated Water ◽  
Alternating Voltage

Cement-based materials prepared with activated water induced by a magnetic field or electric field represent a possible solution to environmental issues caused by the worldwide utilization of chemical admixtures. In this contribution, electric- and magnetic-activated water have been produced. The workability and mechanical properties of cement mortar prepared with this activated water have been investigated. The results indicate that the pH and absorbance (Abs) values of the water varied as the electric and magnetic field changed, and their values increased significantly, exhibiting improved activity compared with that of the untreated water. In addition, activated water still retains activity within 30 min of the resting time. The fluidity of the cement paste prepared with electric-activated water was significantly larger than that of the untreated paste. However, the level of improvement differed with the worst performance resulting from cement paste prepared with alternating voltage activated water. In terms of mechanical properties, both compressive strength and flexural strength obtained its maximum values at 280 mT with two processing cycles. The compressive strength increased 26% as the curing time increased from 7 days to 28 days and flexural strength increased by 31%. In addition, through the introduction of magnetic-activated water into cement mortar, the mechanical strength can be maintained without losing its workability when the amount of cement is reduced.

scholarly journals Properties of Calcium Sulfoaluminate Cement Mortar Modified by Hydroxyethyl Methyl Celluloses with Different Degrees of Substitution

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2136
Author(s):  
Shaokang Zhang ◽  
Ru Wang ◽  
Linglin Xu ◽  
Andreas Hecker ◽  
Horst-Michael Ludwig ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Bond Strength ◽  
Cement Mortar ◽  
Retention Rate ◽  
Methyl Cellulose ◽  
Tensile Bond Strength ◽  
Calcium Sulfoaluminate Cement ◽  
Calcium Sulfoaluminate ◽  
Cement Mortars

This paper studies the influence of hydroxyethyl methyl cellulose (HEMC) on the properties of calcium sulfoaluminate (CSA) cement mortar. In order to explore the applicability of different HEMCs in CSA cement mortars, HEMCs with higher and lower molar substitution (MS)/degree of substitution (DS) and polyacrylamide (PAAm) modification were used. At the same time, two kinds of CSA cements with different contents of ye’elimite were selected. Properties of cement mortar in fresh and hardened states were investigated, including the fluidity, consistency and water-retention rate of fresh mortar and the compressive strength, flexural strength, tensile bond strength and dry shrinkage rate of hardened mortar. The porosity and pore size distribution were also analyzed by mercury intrusion porosimetry (MIP). Results show that HEMCs improve the fresh state properties and tensile bond strength of both types of CSA cement mortars. However, the compressive strength of CSA cement mortars is greatly decreased by the addition of HEMCs, and the flexural strength is decreased slightly. The MIP measurement shows that HEMCs increase the amount of micron-level pores and the porosity. The HEMCs with different MS/DS have different effects on the improvement of tensile bond strength in different CSA cement mortars. PAAm modification can improve the tensile bond strength of HEMC-modified CSA cement mortar.

scholarly journals Assessment of the Rheological and Mechanical Properties of Geopolymer Concrete Comprising Fly Ash and Fluid Catalytic Cracking Residue as Aluminosilicate Precursor

2021 ◽  
Vol 11 (7) ◽  
pp. 3032
Author(s):  
Tuan Anh Le ◽  
Sinh Hoang Le ◽  
Thuy Ninh Nguyen ◽  
Khoa Tan Nguyen
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Fly Ash ◽  
Flexural Strength ◽  
Catalytic Cracking ◽  
Fluid Catalytic Cracking ◽  
High Alumina ◽  
Geopolymer Concrete ◽  
Sem Images

The use of fluid catalytic cracking (FCC) by-products as aluminosilicate precursors in geopolymer binders has attracted significant interest from researchers in recent years owing to their high alumina and silica contents. Introduced in this study is the use of geopolymer concrete comprising FCC residue combined with fly ash as the requisite source of aluminosilicate. Fly ash was replaced with various FCC residue contents ranging from 0–100% by mass of binder. Results from standard testing methods showed that geopolymer concrete rheological properties such as yield stress and plastic viscosity as well as mechanical properties including compressive strength, flexural strength, and elastic modulus were affected significantly by the FCC residue content. With alkali liquid to geopolymer solid ratios (AL:GS) of 0.4 and 0.5, a reduction in compressive and flexural strength was observed in the case of geopolymer concrete with increasing FCC residue content. On the contrary, geopolymer concrete with increasing FCC residue content exhibited improved strength with an AL:GS ratio of 0.65. Relationships enabling estimation of geopolymer elastic modulus based on compressive strength were investigated. Scanning electron microscope (SEM) images and X-ray diffraction (XRD) patterns revealed that the final product from the geopolymerization process consisting of FCC residue was similar to fly ash-based geopolymer concrete. These observations highlight the potential of FCC residue as an aluminosilicate source for geopolymer products.

scholarly journals Interaction of Bioactive Mono-Terpenes with Egg Yolk on Ice Cream Physicochemical Properties

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1686
Author(s):  
Mostafa Gouda ◽  
Long Sheng ◽  
Rana Muhammad Aadil ◽  
Yuanyuan Liu ◽  
Meihu Ma ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Water Distribution ◽  
Structural Characteristics ◽  
Viscosity Index ◽  
Control Sample ◽  
Ice Cream ◽  
Egg Yolk ◽  
Control Treatment ◽  
Non Invasive ◽  
Magnetic Resonance Imaging Mri

Using natural multi-function phytochemicals could be one of the best solutions for clean-label production. In this study, dairy ice creams were prepared containing 14% egg yolk and 0.1% of thymol (THY), trans-cinnamaldehyde (TC), menthol (MEN), or vanillin (VAN). Then, the physical, chemical, and structural characteristics were evaluated. Magnetic resonance imaging (MRI) analysis (a rapid, chemical-free, and non-invasive tool) was carried out to evaluate the water distribution. A multivariate analysis was conducted among all studied variables. According to the results, the overrun of the MEN ice cream was significantly increased as compared to the control sample. The density was also reduced in the MEN sample. Meanwhile, the spreadability (%) of VAN was significantly increased after 6 min as compared to the control treatment. MRI analysis revealed that water distribution was significantly changed in the THY group. The firmness and viscosity of THY samples were significantly increased (p < 0.05). Multivariate analysis indicated that viscosity index and consistency were the top parameters affected by THY. The authors concluded that THY and VAN are promising stabilizers for ice-cream clean production.

Sign in / Sign up

Export Citation Format

Share Document