Title:
Structural Behavior of Reinforced Infra-Lightweight Concrete (ILC)
Author(s):
Alex Hückler and Mike Schlaich
Publication:
Structural Journal
Volume:
116
Issue:
2
Appears on pages(s):
3-14
Keywords:
beam test; bending; bond; cracks; deformation; ductility; fiberreinforced polymer; infra-lightweight concrete (ILC); tension stiffening
DOI:
10.14359/51712273
Date:
3/1/2019
Abstract:
Infra-lightweight concrete (ILC) is a high-performance lightweight-aggregate concrete (HPLWAC) with a dry density of less than 800 kg/m3 (50 lb/ft3). Such low density means low thermal conductivity (increased thermal resistance [R-value]) and thus allows for monolithic and fair-faced concrete structures without any additional heat insulation. This paper summarizes a comprehensive program that investigated the bond and crack behavior of reinforced ILC as well as the flexural behavior of ILC beams. The scope of experimental tests included 60 reinforced ILC specimens (plus reinforced normal concrete [NC] specimens for reference) for each type: pullout test; tension stiffening test; and beam test. Lightweight concrete (LC) with such low densities shows a linear-elastic behavior and is brittle. Research findings indicate rigid bond properties that bring about favorable crack behavior. The paper describes calculation models for bond, cracks, and bending considering such material behavior. The theoretical and experimental research presented herein also gives insight into the ductility of ILC beams.
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