The R value of a material is the thermal resistance of the material, so is dependent on the material's thickness. R is also the inverse of a material's thermal conductivity U.
To work it out you need the k value ( the thermal conductivity) of the material and the thickness, then R=thickness/k.
The k value for structural concrete (of density 2300kg/m3) is 1.6 W/mK (Units: Watts / (metre x degrees Kelvin) so for a thickness 100mm (0.1m) of this concrete, R=0.06 m2°C/W.
Note that the R value in imperial units will not be the same. Check the units for any R value of any material that is given.
Yes. Don't know for sure but its pretty low. however note that R value depends on the thickness. You double the thickness you double the R value.
What is the value of R. Colao - Print No. 246 Arrangement with Copper
$75000 TO $250000
trinity trade foamed concrete Concrete foam insulation is 100% Fireproof and that is one its major selling points over other forms of home insulation. It is also 100% Mold Proof including all types of toxic mold There is no leaching of toxic gasses, it is 100% Non-Toxic, Free of CFC's & Formaldehyde Concrete foam insulation offers a very high R-value, No loss of R-value over time If offers excellent soundproofing qualities. Once in place it is Non-Shrinking and Non-Settling There are no future disposal problems and it is Non-Hazardous as waste It is fully bug and Rodent Proof The primary components of concrete foam insulation are cement which is made of calcium, magnesium oxide and alumina, water and air. When the home is demolished in the distant future no harmful waste is produced. What remains of the concrete foam insulation is easily broken down and remains inert in a landfill. It can also be crushed and repurposed in the future. Concrete foam insulation is blown in to walls and cavities and once in place provides an outstanding R-value plus all of the benefits listed above. It has been installed in the National Audubon Societies headquarters and even Nobel prize winner Al Gore's estate. Because the cement destroys bugs protective coatings they do not nest or live in walls that have been sprayed with it. There are no ozone destroying gasses or off gassing of toxic gasses into the home as some insulations cause. beijing trintiy trade is one maker of concrete foam insulation http://www.foamed.com.cn
$1,000 ---- $10,000
Normal Weight Concrete at 150 pcf has an R value of 1.22 per inch thickness
fiberglass
Fiberglass Insulation, R Value of 3.14. Pine board has an R Value of 1.74
To provide the same insulation value as 3.5 inches of fiberglass, a concrete wall would need to be approximately 15-18 inches thick. Concrete is a poor insulator compared to fiberglass, so a much thicker wall is needed to achieve similar insulation properties. Alternatively, adding insulation material within the concrete wall can help improve its insulating capabilities.
That is depending on your KL/r value . sammy Structural engineer That is depending on your KL/r value . sammy Structural engineer
Yes. Don't know for sure but its pretty low. however note that R value depends on the thickness. You double the thickness you double the R value.
what is the slump value for M20 concrete
R. J. Currie has written: 'Carbonation depths in structural-quality concrete' -- subject(s): Concrete, Concrete construction
D concrete which r mixed in d site itself is known as in situ concrete:)
Concrete does not have a very good insulating value, and neither does steel. The mixture of the two will add structural stability to what you are building, but it (commonly) will not enhance the concrete's insulating value.
Ward R. Malisch has written: 'Aggregates for concrete' -- subject(s): Aggregates (Building materials), Concrete
R. H. H. Kirkham has written: 'The compaction of concrete road slabs' -- subject(s): Concrete slabs, Testing, Vibrators, Vibrated concrete