Title:
Analytical Model for Confined Lightweight Aggregate Concrete
Author(s):
Yoo-Jae Kim and Thomas G. Harmon
Publication:
Structural Journal
Volume:
103
Issue:
2
Appears on pages(s):
263-270
Keywords:
composite; confinement; constitutive model; lightweight concrete; voids.
DOI:
10.14359/15184
Date:
3/1/2006
Abstract:
A model for the uniaxial compressive stress-strain relationship for confined aerated lightweight aggregate concrete was developed. Concrete cylinders confined by either glass or carbon fiber wrap were then tested to determine behavior and to verify the model. The fiber versus concrete volume ratios for glass fiber sleeves were 1.4 and 2% and the carbon fiber sleeves were 2 and 4%. Concrete specimens (1440 and 1600 kg/m3) were tested to address the effect of concrete stiffness and unit weight. The experimental data were used to verify a uniaxial constitutive model based on the frictiondilatancy behavior of concrete cracks. The model uses a unique shear friction model developed for normalweight concrete. An existing stress/strain model for confined normalweight concrete was modified to incorporate strains due to collapse of internal voids. An additional modification was the introduction of a variable angle of internal slip, where the angle minimizes the normal stress on the slip surface. The modified model showed improved correlation with the experimental data.