Thermal Insulating and Constructive Foamed Concrete on a Composite Gypsum Binder

2019 ◽  
Vol 974 ◽  
pp. 125-130 ◽  
Author(s):  
Natalia V. Chernyisheva ◽  
Svetlana V. Shatalova ◽  
Maria Yu. Drebezgova ◽  
Evgeniy N. Lesnichenko
Keyword(s):  
Concrete Mixture ◽  
Foam Concrete ◽  
Thermal Insulating ◽  
Mineral Addition ◽  
Foamed Concrete ◽  
Stepwise Loading ◽  
Cellular Concrete ◽  
Loading Scheme

The article discusses the possibility of obtaining the effective thermal insulating and constructive foamed concrete on a composite gypsum binder. The composition was selected, the stepwise loading scheme of the foam concrete mixture components was proposed, the properties and microstructure of cellular concrete based on a composite gypsum binder with mineral addition of finely-dispersed concrete scrap were studied.

scholarly journals EFFECT OF POROUS STRUCTURE ON SOUND ABSORPTION OF CELLULAR CONCRETE

2020 ◽  
Vol 3 (2) ◽  
pp. 5-18 ◽  
Author(s):  
R.S. Fedyuk ◽  
A. Baranov ◽  
Y.H. Mugahed Amran
Keyword(s):  
Open Porosity ◽  
Sound Absorption ◽  
Concrete Mixture ◽  
Sound Waves ◽  
Foam Concrete ◽  
Mechanical Adhesion ◽  
The Matrix ◽  
Reduce Shear Stress ◽  
The Mathematical Model ◽  
Cellular Concrete

the compositions of gas and foam concrete with improved acoustic characteristics were developed. The optimal form of porosity, which contributes to the absorption of sound waves, both in the range of audible frequencies and at infrasonic and ultrasonic frequencies, is revealed. The mathematical model for designing sound-absorbing concrete was improved, taking into account both the porosity of the composite and the influence of the porous aggregate. The laws of synthesis of aerated concrete and foam concrete are established, which consist in optimizing the processes of structure formation due to the use of a polymineral cement-ash binder and blowing agent. The composition of the composite intensifies the process of hydration of the system, which leads to the synthesis of a polymineral heterodisperse matrix with an open porosity of more than 60%. Peculiarities of the influence of the “Portland cement – aluminosilicate – complex of modifiers” system on the rheology of the concrete mixture was identified, which can significantly reduce shear stress and create easily formed cellular concrete mixtures. The increased activity and granulometry of aluminosilicates predetermine an increase in the number of contacts and mechanical adhesion between particles during compaction, strengthening the frame of inter-pore septa. The mechanism of the influence of the composition of the concrete mixture on the microstructure of the composite is established. The presence of refined aluminosilicates and a complex of additives in the system along with cement contribute to the synthesis of the matrix with open porosity, thereby increasing the sound absorption coefficient.

Rational Proportion For Mixture Of Foamed Concrete Design

2011 ◽  
Author(s):  
Fahrizal Zulkarnain ◽  
Mahyuddin Ramli
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Silica Fume ◽  
Mineral Admixture ◽  
Concrete Mixture ◽  
Foam Concrete ◽  
Foamed Concrete ◽  
Mixed Mortar ◽  
And Control ◽  
Lightweight Foam

Kajian ini membentangkan sebahagian hasil kerja makmal untuk reka bentuk konkrit ringan berbusa dengan Protein Agent 1 sebagai busa, silica fume (SF) sebagai bahan tambah dan superplasticizer (SP). Konkrit ringan berbusa terkawal dicampurkan dengan kandungan simen Portland biasa (OPC) dan silica fume, campuran tersebut pada kadar 10 peratus, dari berat simen sebagai bahan tambah akan disediakan. Silica fume digunakan untuk meningkatkan kekuatan mampat dan juga menjimatkan kos. Konkrit berbusa diawetkan pada kisaran 70 peratus kelembapan dan 28 darjah kandungan udara. Sifat mekanikal daripada struktur konkrit ringan berbusa juga didedahkan. Dapatan kajian menunjukkan bahawa serapan air dalam kajian besar adanya. Walaupun demikian, silica fume perlu digunakan untuk menghasilkan struktur ringan berbusa yang murah dan mesra alam, dengan kekuatan mampat dan kawalan struktur ringan berbusa menggunakan simen Portland biasa (OPC) sahaja. Kata kunci: Campuran konkrit berbusa; ketumpatan mortar; ketumpatan sebenar; sifat mekanikal; kekuatan mampat This paper presents part of the results of laboratory work to design a lightweight foamed concrete made with Protein Agent 1 as foam, silica fume (SF) mineral admixture and superplasticizer (SP). Control of foamed concrete mixture made with foam containing only Ordinary Portland Cement (OPC) and SF, lightweight foam concrete mixture containing 10% of SF as a replacement for the cement in weight basis was prepared. SF is used to increase the compressive strength and for economical concerns. The foam concrete was cured at 70% relative humidity and ± 28°C temperature. The mechanical properties of a lightweight foam concrete with OPC are presented. The findings indicate that water absorption of aggregate is large in this case. However, the use of SF seems to be necessary for the production of cheaper and environmentfriendly structural foamed concrete with compressive strength and control structural foamed concrete containing only OPC. Key words: Foam concrete mixed; mortar density; actual density; mechanical properties; compressive strength

scholarly journals Influence of cellulose fibers on structure and properties of fiber reinforced foam concrete

2018 ◽  
Vol 143 ◽  
pp. 02008 ◽  
Author(s):  
Valeriy Fedorov ◽  
Aleksey Mestnikov
Keyword(s):  
Cellulose Fiber ◽  
Cellulose Fibers ◽  
Cement Matrix ◽  
Structure And Properties ◽  
Hydration Products ◽  
Fiber Reinforced ◽  
Foam Concrete ◽  
Thermal Insulating ◽  
Concrete Quality ◽  
Foamed Concrete

One of the promising means of foamed concrete quality improvement is micro-reinforcement by adding synthetic and mineral fibers to the base mix. This research is the first to investigate peculiarities of using recycled cellulose fiber extracted from waste paper for obtaining fiber reinforced foam concrete. The paper presents results of experimental research on the influence of cellulose fibers on structure and properties of fiber reinforced foam concrete by using methods of chemical analysis and scanning electron microscopy. The research determines peculiarities of new formations appearance and densification of binder hydration products in the contact zone between fiber and cement matrix, which boost mechanical strength of fiber reinforced foam concrete. Physico-mechanical properties of fiber reinforced foam concrete were defined depending on the amount of recycled cellulose fiber added to the base mix. It was found that the use of recycled cellulose fibers allows obtaining structural thermal insulating fiber reinforced foam concretes of non-autoclaved hardening of brand D600 with regard to mean density with the following improved properties: compressive strength increased by 35% compared to basic samples, higher stability of foamed concrete mix and decreased shrinkage deformation.

scholarly journals KINETICS OF RHEOLOGICAL CHARACTERISTICS OF FOAM CONCRETE MIXTURE

2021 ◽  
pp. 110-118
Author(s):  
V. Martynov ◽  
◽  
O. Martynova ◽  
V. Elkin ◽  
S. Makarova ◽  
...  
Keyword(s):  
Structural Strength ◽  
Solid Phase ◽  
Chemical Activation ◽  
Experimental Studies ◽  
Concrete Mixture ◽  
Rheological Characteristics ◽  
Foam Concrete ◽  
Plastic Strength ◽  
Kinetics Of ◽  
Cellular Concrete

Abstract. The results of experimental studies are presented, the purpose of which was to study the influence of variable formulation and technological factors on the rheological characteristics of the foam concrete mixture, in particular, the structural strength. This is preceded by an analysis of the process of structure formation of cellular concrete. As a result, it is shown that the properties of cellular concrete are determined by the nature of the distribution of the solid component. The structure of the solid phase is formed at the earliest stages of the formation of cellular products and depends on the rheological characteristics of the mortar and cellular mixture. In the technology of cellular concrete, it is important to synchronize the processes of pore formation and the growth of plastic (structural) strength, which is also associated with a change in the rheological properties of the mixture. Using the methods of mathematical statistics, the influence of the content of the filler in the mixture with cement, the content of the complex additive, and the effect of mechanical chemical activation on the kinetics of the plastic strength of the foam concrete mixture were studied. The kinetic dependences of the plastic strength of the foam concrete mixture in the range of 6 ... 24 hours from the moment of manufacture have been constructed. Each of the 15 curves is maximized by a 3rd-degree polynomial. Based on the obtained dependences, they are differentiated between the first and second derivatives. As a result, the equations of the speed and intensity (acceleration) of the plastic strength of the foam concrete mixture were obtained. According to the results of the previous experiment, carried out according to a three-factor plan, a 4-factor plan was synthesized, in which the aging period of the foam concrete mixture was taken as the fourth factor. The calculated theoretical values of the characteristics of the structural strength of the foam concrete mixture were entered into the matrix. As a result, mathematical models of plastic strength, speed, and intensity of plastic strength of the foam concrete mixture were calculated and the influence of variable factors studied on the isosurfaces of these properties was visualized. The analysis of these dependencies made it possible to determine the characteristic recipe and technological conditions for obtaining a foam concrete mixture with the required values of plastic strength.

scholarly journals Effects of the Geometric Parameters of Mixer on the Mixing Process of Foam Concrete Mixture and Its Energy Efficiency

2020 ◽  
Vol 10 (22) ◽  
pp. 8055
Author(s):  
Sergey A. Stel’makh ◽  
Evgenii M. Shcherban’ ◽  
Anatolii I. Shuiskii ◽  
Al’bert Yu. Prokopov ◽  
Sergey M. Madatyan ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Lower Energy ◽  
Geometric Parameters ◽  
Concrete Mixture ◽  
Mixing Process ◽  
Conical Part ◽  
Foam Concrete ◽  
Optimal Range ◽  
Optimal Values

The paper studies the influence of the geometric parameters of the mixer on the mixing process, the construction of the mixing body, its location in the mixer bulk, and the mixer shape and geometry. The technique of calculating the power spent on mixing the foam concrete mixture is described. The effects of the ratio of the mixture height to the mixer diameter, the number and width of reflective partitions, and the shape of the conical part of the mixer on the homogeneity of the foam concrete mixture and the power consumption are considered. The optimal ratios of the foam concrete mixture height to the mixer diameter have been determined. Moreover, the optimal range of the ratios of the partition width to the mixer diameter has been established, in order to obtain a homogeneous foam concrete mixture throughout the volume with lower energy consumption. The optimal values of the angle of the mixer conical part for the preparation of a foam concrete mixture have been determined.

Impact of Superplasticizing Agents on Physical and Mechanical Properties of Cellular Concrete

2019 ◽  
Vol 974 ◽  
pp. 181-186
Author(s):  
V.A. Perfilov ◽  
V.V. Gabova ◽  
Inessa A. Tomareva
Keyword(s):  
Mechanical Properties ◽  
Pore Structure ◽  
Pore Space ◽  
Experimental Studies ◽  
Basalt Fiber ◽  
Physical And Mechanical Properties ◽  
Foam Concrete ◽  
Cellular Concrete

The effect of superplasticizing, foam agents, various fiber aggregates on the physical and mechanical properties of cellular concrete has been studied. The article covers the results of experimental studies conducted to determine the effect of foam agents PO-6 and PB-2000, as well as polymeric and basalt fiber on the pore structure of foam concrete. The dependence between the change in density and strength of cellular concrete and the structure of its pore space has been determined.

Effect of Volcanic Rock Powder on Performance of Foamed Concrete

2014 ◽  
Vol 1033-1034 ◽  
pp. 887-891
Author(s):  
Kui Fan Su ◽  
Bo Jiang ◽  
Jiang Shan Lian ◽  
Pei Cheng Qin ◽  
Si Zhi He ◽  
...  
Keyword(s):  
Portland Cement ◽  
Volcanic Rock ◽  
Dry Density ◽  
Foam Concrete ◽  
Cement Slurry ◽  
Rock Powder ◽  
Foamed Concrete ◽  
Powder Addition ◽  
Powder Content ◽  
Curing Age

Foamed concrete is prepared by the use of volcanic rock powder and ordinary portland cement and by means of chemical foaming method. The chemical composition and morphology of volcanic rock powder are analyzed,and the effect of volcanic rock powder addition into the portland cement slurry on the properties of foamed concrete is discussed.The results that the properties of the foam concrete could be prepared by controlling the addition of the volcanic rock powder content is 20%, The Compressive strength is as high as 1.36Mpa. The thermal conductivity is 0.048W/(m·K) and the dry density is 254kg/m3 for 28 days curing age. The main compositions of volcanic rock powder is SiO2 and the volcanic rock has a large number of closed and open pores.

Cement Foam Concrete with Low Shrinkage

2015 ◽  
Vol 1085 ◽  
pp. 245-249 ◽  
Author(s):  
Alexander I. Kudyakov ◽  
Alexey B. Steshenko
Keyword(s):  
Thermal Conductivity ◽  
Shrinkage Strain ◽  
Concrete Mixture ◽  
Fiber Reinforced ◽  
Foam Concrete ◽  
Synthetic Fibers ◽  
Reinforced Cement

The results of studies of fiber reinforced cement foam concrete with mineral and synthetic fibers are given in the article. Introduction of fibers in the amount of 0.1-2% of the weight of cement in the foam concrete mixture enables increase in the strength of the foam concrete in 28 days by 2.5 -fold, decrease in the thermal conductivity by 30-40% and the shrinkage strain by 42-90%.

scholarly journals Research of the mineral additives influence on aggregative stability of foam concrete mixture

2021 ◽  
Vol 2131 (4) ◽  
pp. 042034
Author(s):  
E Bartenjeva
Keyword(s):  
Aggregate Stability ◽  
Stable Structure ◽  
Concrete Mixture ◽  
Aggregative Stability ◽  
Cement Stone ◽  
Foam Concrete ◽  
Effect Of Additives ◽  
Modifying Effect ◽  
The Stability ◽  
Mineral Additives

Abstract An effective method for increasing the aggregate stability of non-autoclave heat-insulating foam concrete is proposed. This material is prepared using a two-stage technology on a turbulent-type installation. An increase in the stability of the foam in the mortar mixture by 9.5-23% has been established. An increase in the viscosity of the foam concrete mixture by 13.5% was revealed. Wollastonite and diopside are actively involved in the formation of a stable structure of foam concrete and are structurally modifying centers. The introduction of mineral additives contributes to the formation of a homogeneous stable structure of non-autoclave foam concrete. Thus, an increase in the stability of the cellular system in the technology of non-autoclave cement-ash foam concrete is possible due to the control of the processes of structure formation when using dispersed mineral additives of wollastonite and diopside. Due to the structural-modifying effect of additives as crystallization centers for neoplasms, a more complete hydration of the cement and a strong contact of the additives with the cement stone should be ensured

scholarly journals OPTIMIZATION OF RECEPTURAL-TECHNOLOGICAL PARAMETERS OF MANUFACTURE OF CELLULAR CONCRETE MIXTURE

2020 ◽  
pp. 30-36 ◽  
Author(s):  
Nataliya Alfimova ◽  
Sevda Pirieva ◽  
D. Gudov ◽  
I. Shurakov ◽  
Elena Korbut
Keyword(s):  
Production Efficiency ◽  
Mechanical Characteristics ◽  
Average Density ◽  
Concrete Mixture ◽  
Technological Parameters ◽  
Number Of Factors ◽  
Aerated Concrete ◽  
The Moment ◽  
The Impact ◽  
Cellular Concrete

aerated concrete at the moment is one of the perspective thermal insulation materials. However, the production of high-quality aerated concrete products is associated with a number of difficulties, primarily related to the features of the manufacturing technology and, in particular, to the formation of its structure during the period of gas evolution and the impact on this process of a large number of factors. The best conditions for the formation of cellular concrete are created when the maximum gas release and the optimum values of the plasticity-viscous characteristics of the aerated concrete mixture are found. Achieving optimal conditions is extremely difficult, which leads to a deterioration in the physico-mechanical characteristics of the final products. One of the ways to solve this problem is to increase the amount of mixing water, however, along with a positive effect (reducing the viscosity of the system), this leads to a decrease in the gas-holding capacity of the mixture. In this connection, the possibility of increasing the production efficiency of the cellular concrete mixture by optimizing the recipe-technological parameters was considered. With the help of the method of mathematical planning, a three-factor experiment was carried out, as the factors of variation were: the duration of the preliminary aging of the mixture, the dosage of the blowing agent and the water-hard ratio, the output parameters were the compressive strength and the average density of the final products. The obtained results made it possible to reveal the regularities of the change in the output parameters from the variable factors and to establish that the preliminary aging of the mixture before the introduction of the gassing agent positively affects the structure and, as a consequence, the physico-mechanical characteristics of the final products.

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