Heat-Insulating Properties Of Effective Light Weight Concretes For Three-Layer Protecting Coverings Of Buildings

2020 ◽  
pp. 36-44
Keyword(s):  
Raw Materials ◽  
Concrete Mixture ◽  
Structural Concrete ◽  
Foam Polystyrene ◽  
Absolute Volume ◽  
Layer Structures ◽  
Super Plasticizer ◽  
Concrete Coating ◽  
Volume Method ◽  
Insulating Properties

Аt present, an intensive change in the structure and materials of building envelopes is taking place in order to increase the energy efficiency of buildings, as well as to improve their appearance and extending the period of maintenance-free operation. The paper presents the results of studies of the physical-mechanical properties of light polystyrene concrete and effective heat-insulation of three-layer structures based on heat-insulating light and structural heavy concrete. To obtain the concrete mixture, Portland cement, granular foam polystyrene, polycarboxylate super-plasticizer, quartz sand and limestone crushed stone were used. All raw materials were of local origin (Vietnam). The composition of the heavy and light concrete mixture was calculated using the absolute volume method according to the standard of Vietnam, the thermal conductivity of concrete was measured with an appropriate device. It has been established that using local surface components it is possible to obtain structural concrete, as well as polystyrene concrete, which has sufficient tensile and tensile strength during bending and heat conduction in the dry state. From the calculations made with the use of the computer program, it follows that the three-layer reinforced concrete coating slab, consisting of heavy and polystyrene concrete, has better thermal insulation properties compared to a coating of the same thickness of solid and perforated structural concrete, as well as with a panel with foam polystyrene blocks.

scholarly journals Combined effect of limestone fine aggregate and pozzolan on properties of high performance fine-grained concrete

2019 ◽  
Vol 97 ◽  
pp. 02004
Author(s):  
Lam Tang Van ◽  
Dien Vu Kim ◽  
Hung Ngo Xuan ◽  
Doan Tung Lam Nguyen ◽  
Boris Bulgakov ◽  
...  
Keyword(s):  
High Performance ◽  
Corrosion Damage ◽  
Concrete Mixture ◽  
Fine Aggregate ◽  
Test Results ◽  
Natural Sand ◽  
Fine Grained ◽  
Absolute Volume ◽  
Study Support ◽  
Volume Method

This paper used the absolute volume method combined with the experiment to determine the compositions of high performance fine-grained concrete (HPFC) and presented the effect of limestone fine aggregate (LFA) and pozzolan (PU) on the HPFC properties. Test results showed that by increasing the LFA and PU, the workability of the concrete mixture decreased, the maximum slump loss after 90 minutes of mixing was 37.84%, whereas the mechanical properties of HPFC increased. The fine-grained concrete mixture containing 40% PU and LFA completely replaced material for natural sand, the compressive strength of concrete at 28-day increased about 23.87% in comparison to the control mixture. By using the standard NT Build 356, the destruction time of the four specimens tested was of 45, 63, 60 and 61 days, respectively. This result is due to the presence of PU increased the volume of the C-S-H, as well as the density of concrete structure and enhanced the strength of HPFC, thus increased destruction time of specimens used for the assessment of corrosion damage of reinforced in the concrete. The results of the current study support the use of the waste limestone from the quarries as a fine aggregate of green concrete in the future.

scholarly journals Synthesis of Ceramics in Different Colors from Industrial Waste

2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
Mihail Doynov ◽  
Tsvetan Dimitrov ◽  
Maria Kokkori
Keyword(s):  
Industrial Waste ◽  
Raw Materials ◽  
Main Phase ◽  
X Ray Diffraction ◽  
Heating And Cooling ◽  
Pure Oxide ◽  
Thermal And Electrical Properties ◽  
And Diffusion ◽  
Insulating Properties ◽  
Successive Heating

The synthesis of arsenic-free ceramics from industrial waste is studied. Samples of waste containing siliceous material passed the exploitation leap-guard layer shift reactor whose main oxide is -Al2O3and, with the addition of natural raw materials and pure oxide, arsenic-free ceramics were synthesized with thermal and electrical properties related to the main phase of spinel group minerals; solid solutions were also formed in the process of synthesis. Insulating properties were established by successive heating and cooling of the specimen for six cycles. Electrical insulating properties were established by the method of resistance to arcing. The relative density was determined by hydrostatic method and diffusion lines of molecules at the main phase were characterized by X-ray diffraction analysis. The experimental procedures followed in this study allowed mixing on a molecular level due to the small dimensions of the crystallite which in turn explains the relatively high density.

scholarly journals Proposed simplified method of geopolymer concrete mix design

2020 ◽  
Vol 21 ◽  
pp. 31-37
Author(s):  
Ali Abdulhasan Khalaf ◽  
Katalin Kopecskó
Keyword(s):  
Controlling Factors ◽  
Mix Design ◽  
Alkali Activation ◽  
Geopolymer Concrete ◽  
Molar Ratios ◽  
Concrete Mix Design ◽  
Mix Proportion ◽  
Absolute Volume ◽  
Optimal Mix ◽  
Volume Method

The research aims to determine the best combination of the controlling factors that govern geopolymer concrete’s mechanical and physical properties by utilizing industrial waste. Therefore, a review on the controlling factors was conducted. Firstly, it is to identify the controlling factors, namely chemical composition, alkali activation solution, water content, and curing condition. Secondly, understanding the relationship between these controlling factors and the properties of geopolymer concrete. These factors are analysed to the mix proportion components. Finally, a new proportion method is proposed based on combining ACI 211 standard and recommended molar ratios of oxides involved in geopolymer synthesis. The effect of aggregate has been taken into account by applying the absolute volume method in mix design. Based on the results of the study, it is expected to determine the optimal mix proportions based on multi-responses.

scholarly journals EFFICIENCY OF REINFORCEMENT OF TECHNOLOGICAL SOIL BY MINERAL MODIFIERS

2019 ◽  
Vol 4 (7) ◽  
pp. 14-23
Author(s):  
Т. Дмитриева ◽  
T. Dmitrieva ◽  
Н. Куцына ◽  
N. Kucyna ◽  
А. Безродных ◽  
...  
Keyword(s):  
Raw Materials ◽  
Road Construction ◽  
Soil Reinforcement ◽  
Production Costs ◽  
Concrete Mixture ◽  
The Road ◽  
Physicomechanical Characteristics ◽  
Advantages And Disadvantages ◽  
Complex Binder ◽  
Technogenic Raw Materials

The paper discusses the main aspects of soil reinforcement in road construction by adding a binder component to them. The use of this technology allows to solve the problem of high-quality raw materials shortage while improving the physicomechanical characteristics or keeping them at the same level, as well as to increase labor productivity and reduce production costs. The technogenic raw materials for the production of soil concrete were studied, the main physicomechanical characteristics and requirements that must be taken into account when selecting the composition of the soil concrete mixture were analyzed. The paper compares the physicomechanical characteristics of the road composite, reveals the advantages and disadvantages of introducing binder components of various types: cement, cement with modifier and a complex binder. It has been established that the introduction of a complex binder or cement with modifier contributes to the improvement of the physicomechanical characteristics while reducing the consumption of cement in the composition of the soil-concrete mixture compared to traditional soil-concrete with cement.

Development of New Advanced Plasters with Waste Fibers Content

2018 ◽  
Vol 276 ◽  
pp. 248-253
Author(s):  
Jiří Zach ◽  
Jitka Peterková ◽  
Vítězslav Novák
Keyword(s):  
Mechanical Properties ◽  
Building Materials ◽  
Raw Materials ◽  
Cellulose Fibers ◽  
Positive Influence ◽  
Point Of View ◽  
Pet Bottles ◽  
Thermal Insulating ◽  
Insulating Properties ◽  
Recycled Waste

The paper deals with the possibilities of using secondary raw materials in the development of new advanced lightweight plasters. It was about fibers from recycled waste materials (waste paper, PET bottles, tyres) and recycled insulation (stone wool). The aim of adding fibers to these lightweight building materials was improvement of mechanical properties, improvement thermal insulation properties and reduction of crack sensitivity. It can be stated, based on the evaluation of the selected measurements, that both types of cellulose fibers and fibers from recycled tyres had positive influence on the mechanical properties, namely in the case of compressive strength. From the point of view of thermal insulating properties, it can be said that only 2 types of fibers have reduced the value of the thermal conductivity. They were mixtures with stone fibers and with recycled tyres fibers. Both of these mixtures also showed the lowest average values of bulk density. Based on the carried out research works can be it concluded that the use of recycled tyres fibers show as optimal.

scholarly journals Mechanical Properties of Manufactured-Sand Concrete after High Temperatures

2015 ◽  
Vol 9 (1) ◽  
pp. 1007-1011
Author(s):  
Zhengfa Chen ◽  
Hehua Zhu ◽  
Zhiguo Yan ◽  
Gaojv Peng
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Mass Loss ◽  
High Temperatures ◽  
Residual Strength ◽  
Elevated Temperatures ◽  
Raw Materials ◽  
Concrete Mixture ◽  
Calculation Formula ◽  
Manufactured Sand

In this paper, to study mechanical properties of manufactured-sand concrete after high temperatures, experiments on the residual strength of manufactured-sand concrete were carried out under high temperatures in which raw materials performances and concrete mixture proportion were considered. The mechanism of elevated temperatures on residual strength was theoretically discussed, and the calculation formula of residual strength was given. The results indicated that with the increasing of temperature, the mass loss was small while the reducing of strength and the elastic modulus of manufactured-sand concrete were significantly.

scholarly journals Influence of the Type of Aggregate from Industrial Waste on Corrosion Resistance of Modified Fine-Grained Concrete

Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 352
Author(s):  
Ljajsjan Zajceva ◽  
Ekaterina Lucyk ◽  
Tat’jana Latypova ◽  
Valerij Latypov ◽  
Pavel Fedorov ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Industrial Waste ◽  
Raw Materials ◽  
Mineral Wool ◽  
Concrete Mixture ◽  
Green Technologies ◽  
Widespread Application ◽  
Waste Products ◽  
Natural Resource Conservation ◽  
Use Of Resources

The development and implementation of “green” technologies in the construction sector, which ensure natural resource conservation, reduce harmful emissions and provide utilization of industrial waste, are key issues in material engineering of the XXI century. Extensive research has been devoted to solving these issues, including research in the field of concrete science. Still, the issue of developing concrete compositions with increased corrosion resistance remains much less studied. At the same time, reactive aggregates from industrial waste can have positive effect on durability of concrete, and the best result can be achieved by means of modification of a concrete mixture with highly effective additives. The article presents the research data in two lines—the study of applicability of reactive aggregates from waste products of nonmetallic and ceramic industries, mineral wool production and concrete scrap for production of corrosion-resistant concretes, as well as the assessment of possibility of Portland cement quantity reduction in a concrete mixture on local raw materials due to the introduction of additives based on polycarboxylates. The article presents the research evidence of the effect of dust and clay particles content on the quality of concrete with a polycarboxylate additive. The article describes the studies of corrosion resistance of concrete samples based on production wastes in sulfate environments and under the influence of carbon dioxide. The developed concrete compositions with waste use can be recommended for widespread application, rational use of resources, and production of durable high-quality concretes. The application of additives based on polycarboxylates makes it possible to produce concretes with the reduction of cement consumption in the mixture by 10–20% and decrease in the mode of thermo-wet treatment by two times.

scholarly journals Hardened Properties of Concrete Containing Copper Slag, Rock Dust and Polypropylene Fiber

2019 ◽  
Vol 8 (12) ◽  
pp. 2226-2233
Keyword(s):  
Raw Materials ◽  
Concrete Strength ◽  
Polypropylene Fiber ◽  
Copper Slag ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Conventional Concrete ◽  
Super Plasticizer ◽  
Concrete Mix ◽  
Rock Dust

The concrete is the material that is obtained from concrete forming materials. These raw materials are mixed in particular proportions, these proportions are based on different concrete grades. These concrete grades defines the strength of the concrete. Construction of structures are based upon concrete, the construction process is growing day by day at a huge scale, hence there is more demand for the raw materials. In order to maintain the demand, excessive extractions of raw materials are done, which makes environment more harmful. In order to limit the extraction of natural raw materials that are used for producing concrete mix, alternative supplementary materials are replaced with fine aggregates. This study involves using of alternative supplementary materials as partial replacement of fine aggregate by copper slag and rock dust, copper slag and rock dust are used at various proportions. The various proportions of rock dust and copper slag are 0% to 50% replacement at an increment of 5% interval. Polypropylene fiber is the material that is added as supplementary material to the concrete mix, it is added at constant volume of 1.5% volume of concrete, it is mixed in concrete to improve toughness and reduce shrinkage of concrete. Super plasticizer admixture that is used is Conplast SP430DIS which contains sulphonated naphthalene formaldehyde is added to cement based on site trails which increases the early concrete strength. Combining copper slag, rock dust, polypropylene fiber and super plasticizer admixture in modified concrete gave best results when compared to conventional concrete due to content of silica in copper slag. Hence this combination can be used for further investigation

scholarly journals Concrete mixture grout for printing extruder

2019 ◽  
Vol 135 ◽  
pp. 03072 ◽  
Author(s):  
E. Grigoryan ◽  
A. Babanina ◽  
Andrey Eropkin
Keyword(s):  
Raw Materials ◽  
Concrete Mixture ◽  
Main Role ◽  
Feeding System ◽  
Extrusion Die ◽  
Concrete Mix ◽  
Static Yield ◽  
Dynamic Yield ◽  
Rheological Indices ◽  
Relationship Of

The method of full or partial automation of masonry of stone structures has great prospects. A big hindrance to the development of 3D technology in construction is the need to adapt the concrete mixture to the narrow aperture of the nozzle of the extrusion die. In additive manufacturing, known as 3D printing, properties such as the static and dynamic yield stresses of jointing materials play a main role. The purpose of this article is to define the most optimal concrete mix solution for a printing extruder, which will have the highest rheological indices. In the article was considered the scheme of solution feeding system. The optimum percentage relationship of raw materials included in the watercement solution for further feeding through the nozzle was calculated. The static yield strength of the concrete mixture exceeds 5000 Pa, and the dynamic - above 250 Pa.

scholarly journals Valorization of rice husk ash in ceramic bricks

Cerâmica ◽  
2017 ◽  
Vol 63 (368) ◽  
pp. 490-493 ◽  
Author(s):  
P. Milak ◽  
M. T. Souza ◽  
C. P. Bom ◽  
P. Mantas ◽  
F. Raupp-Pereira ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Raw Materials ◽  
Residential Buildings ◽  
Industrial Wastes ◽  
Drying Process ◽  
Ceramic Samples ◽  
Ceramic Blocks ◽  
Insulating Properties

Abstract Thermal comfort of residential buildings has become an important factor for the performance and functional application of materials in constructive systems. In this scenario, it also takes some concepts related to sustainability, such as the recycling of industrial wastes. Many of these materials, such as rice husk ash (RHA), become interesting mineral alternatives for production of structural and/or sealing ceramics blocks with insulating properties. In this paper, ceramic samples of formulated compositions constituted of natural raw materials (clays) and rice husk ash (8 to 20 wt%) as an alternative mineral source, were appropriated prepared, extruded and then, after drying process at 110 °C, fired at 965 °C for 2 h. The results showed the feasibility of adding rice husk ash in the production of ceramic blocks with porosities in the 16 to 32% range, resulting in a considerable reduction of their thermal conductivities (up to 27%).

Sign in / Sign up

Export Citation Format

Share Document