Since the devastating Jan. 12 earthquake in Haiti, powerful earthquakes have hit Japan, Taiwan, Turkey and most notably Chile, where a magnitude 8.8 earthquake struck on Feb. 27. None of these quakes, however, have come close to causing the damage and death toll of Haiti’s, which their government estimated last month to be over 230,000. Meanwhile Chile, despite suffering one of the most powerful earthquakes in recorded history, has only 500 dead. The difference, according to many engineers, comes down to infrastructure and building practices.
Sergio Vera, assistant professor in the Department of Construction Engineering and Management at the Catholic University of Chile said that building construction in Haiti and Chile is so different that a comparison is even difficult. He pointed to the higher building standards of Chile, which were revised significantly after an earthquake in 1985. “We are a seismic country so the building standards take into account this condition, hence, new buildings resisted the earthquake quite well.” The damage to buildings in Chile was nowhere near the destruction in Haiti.
The preparedness of the Chilean population also helped. “Earthquakes are part of our culture and people know how to react when these events happen,” said Vera. He added that much damage came from tsunamis that hit the coast after the earthquake, rather than the quakes themselves, and that it was old constructions and historic buildings, from fifty years ago or more, made mostly from wood and mud, were the ones that collapsed or suffered the most damage.
Avtar Pall, of Pall Dynamics limited, said that these figures clearly highlight the role of engineering in earthquake safety. “It is not the earthquakes which kill people, it is the falling of buildings,” Pall said. “To prevent such tragedies, strict building code provisions have to be enforced both for new construction as well as for retrofit or upgrade of existing buildings.”
Pall himself is at the origin of a new, cheaper solution, having created an energy dissipating device called Pall friction dampers. These devices have been used in building protection in both Canada and the United States, as well as internationally, including in the construction of Concordia’s Library, Engineering and Computer Science and John Molson Business School buildings. “With the incorporation of energy dissipating devices, a major portion of the seismic energy is dissipated. Therefore, the forces and amplitude of vibrations are greatly reduced, resulting in economical and safer buildings.” Pall hopes that the string of recent earthquakes will spark some changes to the building traditions across the globe.
Building costs vary by nation, mostly due to labour costs, so a building in Canada costs more than in Chile, and it costs more in Chile than in Haiti. But Vera firmly believes if there’s anything the earthquakes have proved, it’s that the cost is well worth it. According to what he read in newspapers, Vera said estimates for rebuilding Chilean cities vary from US $12 billion up to $30 billion.