Heat-Resistant Cement Composites Using Volcanic Pumps and Vermiculite

The results of research on the development of heat-resistant cement composites using volcanic pumice and expanded vermiculite are presented. Compositions of heat-resistant cement composites are proposed that significantly reduce Portland cement consumption and simultaneously improve their heat-resistant properties. The use of basalt fibers in composites makes it possible to increase their strength, crack resistance and heat-resistant properties due to the perception of tensile temperature stresses. Part of the expensive vermiculite can be replaced by pumice without significantly increasing the average density of the composite, while their strength characteristics increase.

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Behavior of Cement Composites Loaded by High Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.824.121 ◽

2015 ◽

Vol 824 ◽

pp. 121-125

Author(s):

Veronika Špedlová ◽

Dana Koňáková

Keyword(s):

High Temperature ◽

Portland Cement ◽

High Temperatures ◽

Experimental Program ◽

Mechanical And Thermal Properties ◽

Cement Composites ◽

Basalt Fibers ◽

Coefficient Of Thermal Conductivity ◽

Aluminous Cement ◽

Better Than

In this paper, there are summarized the results of an experimental program focused on basic, mechanical and thermal properties of cement composites according to the high – temperature loading. Four different materials were studied, which differed in used kind of cement and amount of fibers. As a matrix for studied composites the aluminous cement was chosen because of its resistance in high temperature. For a comparison the Portland cement was also tested. The second main ingredient used to provide better resistance in high temperatures - the basalt aggregate, was mixed in every specimen. The basalt fibers were chosen for two of the measured samples, remaining two ones were tested without fibers. The obtained data in this presented analyses show that the application of the aluminous cement leads to increase (depending on temperature) of porosity, which is the cause of decreasing of the coefficient of thermal conductivity. It can seems, that these cement composites will have low mechanical strength in high temperatures, but because of better sintering, the aluminous cement keeps its strength in high temperatures better than Portland cement.

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Comparison of Refractory and Non-Refractory Components in Cement Composites after High Temperatures Load

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1054.33 ◽

2014 ◽

Vol 1054 ◽

pp. 33-36 ◽

Cited By ~ 1

Author(s):

Ondřej Holčapek ◽

Pavel Reiterman ◽

Marcel Jogl ◽

Petr Konvalinka

Keyword(s):

Mechanical Properties ◽

Portland Cement ◽

High Alumina ◽

Experimental Program ◽

Cement Composites ◽

Basalt Fibers ◽

Temperature Load ◽

The Difference ◽

Strength In Bending

This article shows results of experimental program focused on determination of refractory and non-refractory components for cement composites and those influence on final properties. According to several research works from various universities strength and cohesion in general of common concrete rapidly decrease with temperature higher than 600 °C. To determine the difference between fire-resistance and common components four mixtures were designed. Non-refractory crushed nature silica aggregates and Portland cement compared to high alumina cement Secar®71 with crushed nature basalt aggregates were used. Combination of basalt fibers with two different lengths significantly improves. Basic mechanical properties tensile characteristics such as tensile strength in bending and compressive strength were examined on samples 40 x 40 x 160 mm. Exposure to 600 °C and especially 1000 °C in electric furnace for three hours simulated the high temperature load. Compared to silica aggregates together with Portland cement, where after1000 °C the composite is disintegrated with almost zero strength, the refractory components show considerably better parameters.

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Gypsum-Cement Composites Based on Volcanic Ash

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1011.136 ◽

2020 ◽

Vol 1011 ◽

pp. 136-143

Author(s):

Tolya Khezhev ◽

Tamerlan Badziev ◽

Talib Soblirov ◽

Timur Tamashev

Keyword(s):

Portland Cement ◽

Volcanic Ash ◽

Water Resistance ◽

Central Area ◽

Cement Composite ◽

Strength Properties ◽

Cement Composites ◽

Basalt Fibers ◽

Initial Matrix ◽

Optimization Parameters

The studies’ results to determine the gypsum, ash and Portland cement components proportions, which would ensure a decrease in the specific binder consumption, as well as the ash grain composition’s effect on the properties of the gypsum cement pozzolan composite, are presented. It was revealed that the use of volcanic ash together with Portland cement in gypsum concrete composites allows reducing gypsum consumption by up to 50% without a significant decrease in strength characteristics. At the same time, the developed gypsum concrete composites have increased water resistance. The influence of the ash particle size distribution on the strength properties of the composite is ambiguous; in the compositions with a high ash content it is advisable to use larger fractions, and with a content of less than 50% ash in the composite, - the small fractions. To study the parameters’ effect of the dispersed reinforcement with basalt fibers on the properties of a gypsum-cement composite, an experiment with such a second-order composite rotatable plan as regular hexagon was conducted. It was found that the maximum values of optimization parameters are observed in the central area of the plan with and . The compressive strength of a fiber gypsum cement pozzolan composite increases by 1.15-1.18 times, when bending, by 1.56-1.72 times with respect to the strength of the initial matrix.

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Fiber-Hypsum-Cement-Vermiculite-Concrete Composites Using Volcanic Ash

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1043.67 ◽

2021 ◽

Vol 1043 ◽

pp. 67-71

Author(s):

Tolya Khezhev ◽

Fatima Shogenova ◽

Madina Bugova ◽

Nikolay Kalambet ◽

Inal Tanashev

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Portland Cement ◽

Volcanic Ash ◽

Physical And Mechanical Properties ◽

Regression Equations ◽

Basalt Fibers ◽

Expanded Vermiculite

Fiber-gypsum-cement-vermiculite-concrete composites with use of gypsum, Portland cement, volcanic ash, expanded vermiculite and basalt fibers are considered. The results of studies of the compositions and physical and mechanical properties of fiber-gypsum-cement-vermiculite-concrete composites, the dependence of the composite characteristics on the reinforcement with basalt fibers are presented. Graphical interpretations of regression equations for compressive and flexural strength of composites are presented.

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Sound-Absorbing and Thermal-Insulating Properties of Cement Composite Based on Recycled Rubber from Waste Tires

Applied Sciences ◽

10.3390/app11062725 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2725

Author(s):

Jakub Svoboda ◽

Tomáš Dvorský ◽

Vojtěch Václavík ◽

Jakub Charvát ◽

Kateřina Máčalová ◽

...

Keyword(s):

Building Materials ◽

Absorption Capacity ◽

Acoustic Properties ◽

Strength Characteristics ◽

Cement Composites ◽

Waste Tires ◽

Natural Aggregate ◽

Thermal Insulating ◽

Recycled Rubber ◽

Insulating Properties

This article describes an experimental study aimed at investigating the potential use of recycled rubber granulate from waste tires of fractions 0/1 and 1/3 mm in cement composites as a 100% replacement for natural aggregates. The use of waste in the development and production of new building materials represents an important aspect for the sustainability and protection of the environment. This article is focused on the sound-absorbing and thermal-insulating properties of experimental cement composites based on recycled rubber from waste tires. The article describes the grain characteristics of recycled rubber, sound absorption capacity, thermal conductivity and strength characteristics. The results of this research show that the total replacement of natural aggregate with recycled rubber in cement composites is possible. Replacing natural aggregate with recycled rubber has significantly improved the thermal and acoustic properties of the prepared cement composites, however, at the same time; there was also the expected decrease in the strength characteristics due to the elasticity of rubber.

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Preparation and Mechanical Properties of Polyethylene-Portland Cement Composites

MRS Proceedings ◽

10.1557/proc-1242-s4-p129 ◽

2009 ◽

Vol 1242 ◽

Author(s):

Rivas-Vázquez L.P. ◽

Suárez-Orduña R. ◽

Valera-Zaragoza M. ◽

Máas-Díaz A. De la L. ◽

Ramírez-Vargas E.

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Portland Cement ◽

Plastic Waste ◽

Cement Composites ◽

Compression Tests ◽

Standard Samples ◽

Cement Ratio ◽

Reinforcing Fibers ◽

Waste Polyethylene

ABSTRACTThe effects of waste polyethylene aggregate as admixture agent in Portland cement at different addition polyethylene/cement ratios from 0.0156 to 0.3903 were investigated. The reinforced samples were prepared according the ASTM C 150 Standard (samples of 5 × 5 × 5 cm). The reinforcing fibers were milling at a size of 1/25 in diameter, form waste and used them to evaluate the effects in mechanical properties in cement-based composites. The evaluation of polyethylene as additive was based on results of density and compression tests. The 28-day compressive strength of cement reforced with plastic waste at a replacement polyethylene/cement ratio of 0.0468 was 23.5 MPa compared to the control concrete (7.5 MPa). The density of cement replaced with polyethylene varies from 2.114 (0% polyethylene) to 1.83 g/cm3 by the influence of polyethylene.

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