Behavior under thermal shock of steel fiber reinforced refractory concrete

Author(s): R.D.T. Filho, L.F.L. Rosa, J.D. Vieira, A.C.J. Evangelista, I.F. de Moraes, L.F. Santos, F. Medeiros
Paper category: Conference
Book title: 8th RILEM International Symposium on Fiber Reinforced Concrete: challenges and opportunities (BEFIB 2012)
Editor(s): Joaquim A.O. Barros
Print ISBN: 978-2-35158-132-2
e-ISBN: 978-2-35158-133-9
Publisher: RILEM Publications SARL
Pages: 848 - 858
Total Pages: 10
Language: English

Abstract: 
Refractory concretes are cementing materials produced with calcium aluminate cements which are suitable for use at very high temperatures, up to 2000C. Considering the macroscopic quasi-brittle behavior of this material, metallic fibers are used as reinforcement to increase its bending strength and flexural toughness. In a petroleum refinery, the oil refining process occurs at temperatures of the order of 500-600C and the carbon steel used in the structural elements of the Fluid Catalytic Cracking Units (FCCU’s) are lined with steel fiber reinforced refractory concrete to reduce the temperature in the metallic part of the structure to about 200C. Of great importance is the study of the durability of the refractory concrete to thermo-mechanical loads and chemical attack that can occur during the operation of such units. This paper presents the results of an experimental program aiming to evaluate the response of dense refractory concretes to thermal shocks. Four mixtures were produced, three of which reinforced with stainless steel fibers, in volume fractions of 1.20, 1.50 and 1.80%. In the test, prismatic specimens of 40 x 40 x 160 mm were heated to temperatures of 600ºC in a computer controlled furnace and then cooled down rapidly to a temperature of 24ºC. Twenty thermal shock cycles were applied to the specimens and it was determined the influence of the different fiber volume fractions in controlling the cracking evolution process during the test. Four point bending tests were carried out on the specimens submitted to the thermal shocks and the residual bending strength and flexural toughness were compared with those of the reference concrete, not submitted to the thermal degradation. The results lead to conclude that the fiber addition resulted in a more ductile material with improved response to thermal shocks.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00