Seismic Improvement of Adobe-Mudbrick Walls-Comparison between Internal and External Vertical Reinforcement

Traditional adobe (mudbrick) houses are highly susceptible to damage and destruction during seismic events. This vulnerability is particularly acute in developing countries where traditional construction practices and resource limitations result in large stocks of at-risk houses. This paper presents two reinforcement systems: one with vertical reinforcement within the walls; the other with vertical reinforcement attached to the outside of the walls. (Both systems also include horizontal wire/wire mesh reinforcement and a timber ring beam). Scale model (1:2) u-shaped wall panels were subjected to transient dynamic loading using a shake table to evaluate the response to out-of-plane seismic forces. The testing revealed both systems to be effective at impeding initial cracking, as well as delaying major structural damage and ultimate collapse. The system incorporating external vertical reinforcement performed slightly better, and has the clear advantage of being simpler to construct, as well as being a viable option for the retrofit-strengthening of existing dwellings.