Turkey-Syria earthquake: How can cities build up resilience?
The majority of the more than 1 million buildings damaged or destroyed in rural Nepal featured traditional stone masonry and mud-mortar techniques, on average two stories in height. After surveying the damage, Build Change found that many damaged buildings didn't necessarily have to be torn down and replaced.
"Much of the single family housing damaged in the earthquake could be repaired and strengthened for around $3,000," Hausler told DW. "Given these buildings would cost $20,000 to replace, the cost-benefit of strengthening them was compelling." Through retrofitting — repairing and strengthening unsafe buildings — builders reinforced weak walls, strengthened columns and other support structures and replaced inferior building materials.
Over the years, the construction sector — in Chile and other seismically active regions — has developed techniques designed to reinforce modern high-rises. Gonzalez said there are no height limits for buildings in Chile's seismic design codes. Instead, these high-risk buildings use reinforced concrete columns and beams, supported by steel frames, to develop the flexibility to withstand strong quakes. The concrete beams may break, but the steel reinforcement columns are designed to stay standing and prevent complete collapse.
Surprise inspections at construction sites also ensure that design codes are being followed to the letter. These codes, said Gil, have been steadily improved after every major earthquake dating back to the magnitude 9.5 disaster in May 1960, the most powerful seismic event ever recorded.