Temperature influence on ordinary concrete modified with fly ashes from thermally conversed municipal sewage sludge strength parameters
Künye
Rutkowska, G., Ogrodnik, P., Fronczyk, J., & Bilgin, A. (2020). Temperature Influence on Ordinary Concrete Modified with Fly Ashes from Thermally Conversed Municipal Sewage Sludge Strength Parameters. Materials, 13(22), 5259.Özet
Concrete is the most commonly used structural material, without which modern construction
could not function. It is a material with a high potential to adapt to specific operating conditions.
The use of this potential is made by its material modification. The aim of the performed investigations
was the assessment of rational application possibilities of fly ashes from thermally conversed municipal
sewage sludge as an alternative concrete admixture. A concrete mix was designed, based on the
Portland cement CEM I 42.5R and containing various quantity of ash, amounting to 0–25% of cement
mass. The samples were conditioned and heated in a furnace at the temperature of 300 ◦C, 500 ◦C, and
700 ◦C. Physical and chemical properties of the ashes as well as utility properties of the concrete, i.e.,
density, compressive strength after 28, 56, and 90 days of maturation, frost resistance, and compressive
strength in high temperature were determined. The tests were performed at cubic samples with 10 cm
edge. The replacement of a determined cement quantity by the fly ashes enables obtaining a concrete
composite having good strength parameters. The concrete modified by the fly ashes constituting 20%
of the cement mass achieved its average compressive strength after 28 days of maturation equal to
50.12 MPa, after 56 days 50.61 MPa and after 90 days 50.80 MPa. The temperature growth weakens
the composite structure. The obtained results confirm the possibility of waste recycling in the form of
fly ashes as a cement substitute in concrete manufacturing.