SR265 Effect and remediation of the loss of building lateral stiffness caused by earthquake loading (2018)

Following the devastating Christchurch earthquakes, some homeowners have reported that their houses are noisier when doors are slammed, people climb stairs, heavy vehicles drive by and during strong winds and aftershocks. Often, these houses had only minor apparent earthquake damage. The sensations felt sometimes still occurred after cosmetic repairs.

BRANZ devised an experimental set-up in the laboratory to determine how much more flexible houses become following earthquake shaking and the effect of different repair strategies. A small test house was built and exposed to various levels of lateral displacement. The damage and house stiffness were recorded at each stage of testing.

Several repair methods were used, the amount of restiffening that occurred was measured and recommendations made on the most appropriate repair strategy depending on the degree of plasterboard damage incurred from the earthquake.