The tragedy at the privately owned Enrique Rebsamen school in southern Mexico City, in which seven adults also died, has become a symbol of the devastation inflicted by the country’s 7.1 magnitude quake, the worst in a generation. At least 355 people died in the capital and surrounding states.
“The building was badly designed, poorly calculated and poorly constructed,” said Alfredo Perez, a 52-year old civil engineer who dashed to the school shortly after the Sept. 19 quake to help rescue efforts. “The reinforced concrete doesn’t comply with specifications in construction regulations.”
Alongside rescue workers, Perez said, he pulled bodies from the rubble. Then he sat in one of the undamaged classrooms and drew plans detailing potential design failures in the collapsed building.
While the quantity of steel required under Mexico’s stringent post-1985 building code varies depending on the size of structure, all six engineers said the building’s columns were built with too little steel to withstand strong quakes.
Perez and another engineer specified that columns appeared to have less than half the required amount of steel reinforcement. They base their view on the number of vertical and horizontal steel rebar rods in the columns, which are visible in Reuters photos along with the measurements in Perez’s plans.
“It comes down to the lack of steel,” said Troy Morgan, a New York-based senior managing engineer at Exponent, an engineering consulting firm.
Since a 1985 quake toppled hundreds of buildings in Mexico City, planning officials developed a strict building code at the forefront of international standards for quake-proofing that raised the proportion of required steel reinforcement.
Teachers, current and former students and their families all said she had been at the premises during the quake and survived.
A spokesman for the Tlalpan district where the school was located said property owners are not required to notify authorities of the builders or architects they used for modifications. The spokesman said the district had no record of the builder that worked on the new floors at the school. People living by the school said they did not know who had done the work.
The Mexico City urban development department did not respond to requests for comment on whether the inspectors who certified the school had proper licenses or any history of complaints.
Although the school was founded in 1983, before the new code took effect, the administrative building that buckled was expanded from two to four floors over the last decade or so, neighbors and former students said.
Photos published by Google Maps show the building had four floors as of 2009 with an expansion of the top floor by 2014 and a further expansion in 2016.
“It definitely did not comply with the post-1985 code,” said Eduardo Miranda, a civil and environmental engineering professor at Stanford who collected statistics on buildings that collapsed in Mexico’s 1985 earthquake, citing the code, photos and plans.
Construction permits released by local authorities dated in 1983 and 1984 authorized a four story structure at the school site. The top two floors were added much later, meaning the existing structure should have been brought up to modern standards, according to Mexico City’s construction code.
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