Partially rib precast and cast-in-situ floors with cellular-concrete blocks

The paper presents the results of in-situ research studies and hygrothermal simulations for a fragment of prefabricated cellular concrete wall, insulated with Styrofoam, allowing for two types of external plasters. The disruption of heat and mass transfer is effected by the connector for thermal insulation mounted in the layer of cellular concrete. The carried out research studies and simulations have demonstrated that the impact of the insulation connector with a steel core is observed only locally, but its destructive impact should not be ignored.

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Perméabilité in situ du béton de peau, établie à partir de la percolation d'un gaz en régime d'écoulement permanent

Canadian Journal of Civil Engineering ◽

10.1139/l02-009 ◽

2002 ◽

Vol 29 (3) ◽

pp. 360-368 ◽

Cited By ~ 3

Author(s):

Daniel Perraton ◽

Alan Carter ◽

Michel Vaillancourt ◽

Bruno Lavoie

Keyword(s):

Superficial Layer ◽

Mass Concrete ◽

Construction Site ◽

Intrinsic Permeability ◽

Apparent Permeability ◽

Long Time ◽

Concrete Blocks ◽

The Relationship ◽

Established Technique

In an attempt to apply the concepts developed by Carman and Klinkenberg for the measurement of permeability of a porous media using a gas, a permeameter for the in-situ measurement of intrinsic permeability of skin concrete has been developed. The established technique allows concentration of gas percolation through a well-defined zone in the superficial layer of concrete. The instrument, the measurement method, and the calculation procedure are described in details in this paper. Several series of tests have been performed in laboratory on concrete blocks (300 × 300 × 400 mm) to simulate measurements on the construction site. Three types of concrete, with different porosity, have been tested. The measurement of permeability performed on the concrete blocks have been accomplished both on shaped surfaces, which are representative of skin concrete, and on sawed surfaces, which are representative of mass concrete. Results show that the relationship between the water/cement ratio and the permeability of skin concrete varies distinctively compared with that of mass concrete. The permeameter allows quantification of what has been for a long time qualified as a determining element in terms of the durability of concrete against the corrosion of reinforcement, that is, the distinct permeability of skin concrete from that of mass concrete.Key words: skin concrete, in-situ permeability, intrinsic permeability, apparent permeability, permeameter, Klinkenberg.[Journal translation]

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Increasing the Solidity of Masonry Walls Made of Cellular Concrete Blocks of Autoclave Hardening by using Polyurethane Foam Adhesive Composition as a Masonry Solution

Journal of Physics Conference Series ◽

10.1088/1742-6596/1655/1/012085 ◽

2020 ◽

Vol 1655 ◽

pp. 012085

Author(s):

B K Dzhamuev

Keyword(s):

Polyurethane Foam ◽

Masonry Walls ◽

Adhesive Composition ◽

Concrete Blocks ◽

Cellular Concrete

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Polystyrene Waste in Panels for Thermal Retrofitting of Historical Buildings: Experimental Study

Energies ◽

10.3390/en14071844 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1844

Author(s):

Bożena Orlik-Kożdoń

Keyword(s):

Thermal Conductivity ◽

Thermal Insulation ◽

Resistance Coefficient ◽

Diffusion Resistance ◽

Insulation Material ◽

In Situ Tests ◽

Historical Building ◽

Technical Parameters ◽

Cellular Concrete

The following article presents comprehensive research results for the insulation material based on polystyrene wastes. The presented product has the form of plates to be applied for thermal insulation of external envelopes from the inside. The laboratory tests were focused on the determination of basic technical parameters for this type of materials, i.e., thermal conductivity coefficient, diffusion resistance coefficient, reaction to fire, material sorption, and strength characteristics. For the recycling material, the obtained thermal conductivity value was 0.055 [W/mK]. The diffusion resistance coefficient was 5 [–], and therefore, this component has been qualified to a group of solutions that allow for interstitial condensation in the envelope. For the developed product, in situ tests were carried out on the actual wall system in a historical building. Based on the research, temperature and humidity profiles were obtained in the selected planes of the envelope. The performance of this material in real conditions was observed in relation to the reference product, i.e., lightweight cellular concrete (commonly used as thermal insulation from the inside). For the conducted in situ research, statistical inference was applied, which included the verification of the hypothesis-recycling panels in wall systems follow a trend of changes similar to that of slabs made of lightweight cellular concrete (a group of materials that allows for interstitial condensation). The proposed method of using secondary raw materials in insulation products allows us to obtain a product with high technical parameters that do not differ in quality from new components.

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Production of Cellular Concrete Blocks Espumígeno Using Coconut Fatty Acids and Wastes of Foundry-Review of the Literature

10.47363/jnsrr/2020(2)110 ◽

2020 ◽

pp. 1-5

Author(s):

Rudimar Pedro ◽

◽

Lauren da Cunha Duarte ◽

Tauhana Eineck ◽

Fernanda Vilasbôas ◽

...

Keyword(s):

Fatty Acids ◽

Practical Knowledge ◽

Northern Region ◽

The State ◽

Natural Sand ◽

Environmental Liabilities ◽

Environment And Health ◽

Concrete Blocks ◽

The Cost ◽

Cellular Concrete

The northern region of the state of Rio Grande do Sul, Brazil, is an important polo industrial metal / mechanical, with an extensive and varied portfolio of equipment, principally the manufacture of agricultural implements. In the foundry parts used in the manufacture of agricultural machinery, a large amount of sand is used, generating waste according to the NBR 10004/2004 standard, which deals with the classification of solid waste as its potential risks to the environment and health class II THE. This class includes non-hazardous waste and non-inert. Except in cases of waste containing large amounts of “molds machos’’, in this case framed as ‘’dangerous’’ class I. Its environmentally correct disposal in controlled or sanitary landfills represents an important expense in the cost table and requires careful management for the industries that are directly responsible for incidents and accidents and co-responsible for possible environmental liabilities futures, even with referral to paid landfills. Specifically, this paper seeks search a method of using foundry waste and its blanketing, more precisely, the Sands used in the manner of manufacture of cast piece, Replacing the natural sand, water, foam produced With the espumigeno coconut fatty acids, cement as a binder in the manufacture of blocks of cellular concrete espumígeno (bcce), and consequent use in civil construction. In this context it seeks the state of the art in the construction of theoretical and practical knowledge about the topic, and also based on the models studied in research and publications by this author, using similar residues

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Increasing the Monolithic Nature of Masonry Made of Cellular Concrete Blocks by Using Polyurethane Foam Glue as a Masonry Mortar

Stroitel nye Materialy ◽

10.31659/0585-430x-2020-786-11-4-9 ◽

2020 ◽

Vol 786 (11) ◽

pp. 4-9

Author(s):

DZHAMUEV B.K. ◽

Keyword(s):

Compressive Strength ◽

Polyurethane Foam ◽

Research University ◽

The Body ◽

Axial Tension ◽

Reinforced Masonry ◽

Concrete Blocks ◽

Normal Adhesion ◽

Axial Stretching ◽

Cellular Concrete

This study is a continuation of previously published work [1]. The results of experimental determination of the strength of normal adhesion (under axial tension) in masonry made of autoclave–hardened cellular concrete blocks of compressive strength classes B1,5-B3,5 on cement mortars and polyurethane foam adhesives are presented. The tests were carried out in the laboratory of the Department “Reinforced Concrete and Stone Structures” of the Moscow State University of Civil Engineering (National Research University). The experiment was carried out on samples-cubes with a size of 150x150x150 mm, which were cut out of cellular concrete blocks, fastened (glued) together using masonry (binding) compositions. In the course of the study, it was found that when using various polyurethane foam glue compositions in masonry made of cellular concrete blocks of compressive strength classes B1,5–B3,5, the resistance to axial stretching over an unbound section (normal adhesion) of the masonry increases by approximately 9–25%. It was also found that the nature of the destruction of samples made on polyurethane foam adhesives (destruction occurs along the body of concrete), indicates the monolithic nature of the masonry. The analysis of the results obtained makes it possible to conclude that the resistance to axial tension along the unbound section of the masonry depends on the strength of the material from which the block is made, and not on the compressive strength of the masonry (binder) mortar used, as indicated in table 11 of SP 15.13330.2012 “Stone and reinforced masonry structures”. This factor must be taken into account when calculating masonry from autoclave-hardened cellular concrete blocks on polyurethane foam compositions.

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