Seismic Response of Reinforced Concrete Walls with Lap Splices

Lap-splice failures in reinforced concrete walls and smoke stacks after recent earthquakes (e.g. Izmit, Turkey in 1999, Northridge, United States in 1994, Maule, Chile in 2010) and the scarcity of experimental data revealed the need for this investigation.

Six large-scale reinforced concrete structural walls were subjected to increasing displacement reversals up to failure. The effects of the presence of lap splices, splice length (60 bar diameters and 40 bar diameters), and boundary-element confinement were studied. The aspect ratio of the test walls was 2.2.

The measured drift capacity ranged from 2.5% to 3% for the walls without lap splices and from 1.5% to 2.5% for the walls with lap splices. The increase in drift capacity caused by the boundary-element confining reinforcement ranged between 20% and 67%.

Concrete surface unit strains were measured using an optical tracking system. Tensile unit strain concentration was observed at the base of walls with lap splices. The relative increment in tensile unit strains was approximately 100%. Compressive unit strains were not observed to be sensitive to the presence of the lap splices.

Sponsor: ERICO International Corporation
Faculty Investigator: Santiago Pujol
Graduate Student: Enrique Villalobos