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Research papers, University of Canterbury Library

The recent earthquakes in Christchurch have made it clear that issues exist with current RC frame design in New Zealand. In particular, beam elongation in RC frame buildings was widespread and resulted in numerous buildings being rendered irreparable. Design solutions to overcome this problem are clearly needed, and the slotted beam is one such solution. This system has a distinct advantage over other damage avoidance design systems in that it can be constructed using current industry techniques and conventional reinforcing steel. As the name suggests, the slotted beam incorporates a vertical slot along part of the beam depth at the beam-column interface. Geometric beam elongation is accommodated via opening and closing of these slots during seismically induced rotations, while the top concrete hinge is heavily reinforced to prevent material inelastic elongation. Past research on slotted beams has shown that the bond demand on the bottom longitudinal reinforcement is increased compared with equivalent monolithic systems. Satisfying this increased bond demand through conventional means may yield impractical and economically less viable column dimensions. The same research also indicated that the joint shear mechanism was different to that observed within monolithic joints and that additional horizontal reinforcement was required as a result. Through a combination of theoretical investigation, forensic analysis, and database study, this research addresses the above issues and develops design guidelines. The use of supplementary vertical joint stirrups was investigated as a means of improving bond performance without the need for non-standard reinforcing steel or other hardware. These design guidelines were then validated experimentally with the testing of two 80% scale beam-column sub-assemblies. The revised provisions for bond within the bottom longitudinal reinforcement were found to be adequate while the top longitudinal reinforcement remained nominally elastic throughout both tests. An alternate mechanism was found to govern joint shear behaviour, removing the need for additional horizontal joint reinforcement. Current NZS3101:2006 joint shear reinforcement provisions were found to be more than adequate given the typically larger column depths required rendering the strut mechanism more effective. The test results were then used to further refine design recommendations for practicing engineers. Finally, conclusions and future research requirements were outlined.

Research Papers, Lincoln University

Though there is a broad consensus that communities play a key role in disaster response and recovery, most of the existing work in this area focuses on the activities of donor agencies, formal civil defence authorities, and local/central government. Consequently, there is a paucity of research addressing the on-going actions and activities undertaken by communities and ‘emergent groups’ , particularly as they develop after the immediate civil defence or ‘response’ phase is over. In an attempt to address this gap, this inventory of community-led recovery initiatives was undertaken approximately one year after the most devastating February 2011 earthquake. It is part of on-going project at Lincoln University documenting – and seeking a better understanding of - various emergent communities’ roles in recovery, their challenges, and strategies for overcoming them. This larger project also seeks to better understand how collaborative work between informal and formal recovery efforts might be facilitated at different stages of the process. This inventory was conducted over the December 2011 – February 2012 period and builds on Landcare Research’s Christchurch Earthquake Activity Inventory which was a similar snapshot taken in April 2011. The intention behind conducting this updated inventory is to gain a longitudinal perspective of how community-led recovery activities evolve over time. Each entry is ordered alphabetically and contact details have been provided where possible. A series of keywords have also been assigned that describe the main attributes of each activity to assist searches within this document.This inventory was supported by the Lincoln University Research Fund and the Royal Society Marsden Fund.