Cyclic testing of unbonded post-tensioned concrete wall systems with and without supplemental damping. (1st June 2017)

• Record Type: Journal Article
• Authors: Twigden, K.M.; Sritharan, S.; Henry, R.S.
• Is Part Of: Engineering structures. Volume 140(2017:Jun. 01)
• Page Start: 406
• Page End: 420
• Publication Date: 2017-06-01
• Subjects: Self-centering -- Unbonded post-tensioning -- Precast concrete -- Shear walls -- Cyclic testing -- PreWEC -- O-connector; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2017.02.008
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Experimental tests of four unbonded post-tensioned concrete wall systems. Investigation into supplemental damping using energy dissipating O-connectors. Excellent behaviour achieved with good wall design and detailing. Wall panel behaviour found to be independent of the number of O-connectors. Validation of existing design procedure and simplified analysis method. Abstract: A series of cyclic lateral-load tests were conducted on four different unbonded post-tensioned precast concrete wall systems, including two Single Rocking Walls (SRW) and two PREcast Wall with End Columns (PreWEC). The main purpose of these tests was to systematically investigate the cyclic response of post-tensioned concrete walls with varying amounts of supplemental damping while keeping the initial post-tensioning force, wall dimensions, and confinement details constant. A secondary objective was to validate the wall panel design including the appropriate selection of axial force ratio and design of confinement and armouring details. All of the test walls exhibited excellent performance with uplift and rocking at the wall base with only minor damage observed, consisting of small amounts of spalling in the wall toes. There were consistent observations and measurements of the wall damage, concrete compressive strains, and wall neutral axis depths for both the SRW and PreWEC systems with the same wall panel dimensions. Based on these observations it is concluded that the behaviour of the wall panel in a PreWEC system is independent of the number of energy dissipating O-connectors. The O-connectors increased the hysteretic energy dissipation in the wall system and provided between 1.1% and 1.4% of additional equivalent viscous damping per connector for the PreWEC walls tested. Overall, the behaviour of the four walls tested confirmed the design procedures used, with both the global force-displacement response and local response parameters predicted with sufficient accuracy using an existing simplified analysis method.