Title:
The Effects of High Temperature on the Residual Compressive Strength of High-Strength Siliceous Concretes
Author(s):
Roberto Felicetti and Pietro G. Gambarova
Publication:
Materials Journal
Volume:
95
Issue:
4
Appears on pages(s):
395-406
Keywords:
compressive strength; concrete toughness; high-strength concrete; high
temperature; residual mechanical properties; strain softening; strength recovery
of heated concrete; stress-strain diagrams;
DOI:
10.14359/382
Date:
7/1/1998
Abstract:
The rectangular stress block parameters in the current ACI Code are limited to concrete strengths in the range 20 to 50 MPa (2900 to 7250 psi). This paper looks at the applicability of the ACI rectangular stress block parameters to high-strength concretes. New rectangular stress block parameters are proposed that are based on a probabilistic analysis using a stress-strain relationship for high-strength concrete, and includes estimates of variability and distribution of the input properties. A sensitivity analysis is carried out to ascertain the effect of parameter uncertainty. The probabilistic models proposed can be used in a code calibration of design formulae for high strength concrete. It is shown that for a ductile singly reinforced rectangular section, the ultimate moment capacity is relatively insensitive to the stress block model. Estimates of the ductility level at ultimate and column capacity in primary compression failure are both, however, significantly effected by the choice of the stress block model.