Strengthening foundations: Seismic upgrading at Delta Secondary School

Strengthening foundations

Seismic upgrading at Delta Secondary School

By Tammy Schuster

The school hallways have craters as deep as six feet dug into the floor, the shop class is boarded with plywood, and there is dust everywhere.

Frank Geyer, director of facilities and planning for School District No. 37 (Delta), is at the helm of a two-year major seismic upgrade underway at the Delta Secondary School in Ladner.

Closing off sections of the school, moving classes to different rooms and buildings, and drilling when classes are on break, make way for an intricate choreographed dance of trucks, power tools, and men in vests.

Geyer says the upgrades are designed to ensure the school is capable of withstanding an earthquake. “The seismic upgrade just enhances the safety of the occupants, but people were worried. The building looks like a war zone,” he says. “We are the unofficial complaints department.”

The structural seismic upgrading at Delta Secondary School is part of a major capital project by the Ministry of Education under the School Seismic Mitigation Program.

The program recognized schools with at least one high-priority building that need upgrading. Three schools in Delta met the criteria; South Delta Secondary, which was completed this year; Delta Secondary, which began in the spring; and Gibson Elementary, which is proposed for 2016/2017.

The oldest block of Delta Secondary School was first constructed in the mid‘60s when the impact of a major seismic event was unknown, at least not in the way it is known today.

“The school is basically a multitude

of buildings dating back to 1965,” says Geyer. “There are 19 different components to the school – including additions, demolitions, and connections – which makes upgrading the school such a complicated project.”

Add to that, the school is sitting on land that is considered a high-liquefaction zone. The soil in the Ladner area is made of a sandy silt material that, when severely agitated by something like an earthquake, could liquefy and give out.

With every addition made to the school, a connection was also constructed connecting the past to the present. Because of this combination of technologies and construction, each building would respond differently in the event of liquefaction during an earthquake.

“It would be very safe to say that the majority of the $17.6 million budgeted for this project would go into the foundation structure to make sure that the entire school can still stand after a major event,” says Geyer.

The original plan was for a complete structural seismic resistance upgrade to four blocks of the school – woodwork/ automotive shops, theatre, a classroom block and an arts wing – plus foundation upgrades to the rest of the school. But Geyer says once the team went through the proof-of-concept stage, they discovered that nearly every part of the school would require some level of improvement to the substructure.

“You could upgrade four pieces of the building, but if the other 15 pieces aren’t stable, that could damage the upgraded portions.”

Geyer says in this particular case, the cost of rebuilding the school entirely would be significantly more than upgrading.

“Our cost to remediate the problems is $17.6 million, whereas the cost to replace the building is over $50 million,” he says. “A nice new building would be fabulous, but it’s just not financially or operationally practical.”

In terms of longevity, Geyer says he can’t imagine a need for further upgrades in his lifetime. “We have some of the strongest and most talented engineers in North America. I think the improvements made to the building will give the school at least another 40 to 50 years.”

The biggest challenge on any school renovation or upgrade is working in an operating school. So while engineers, architects, projects managers and construction crews are upgrading the building for safety, their first priority is keeping students and staff safe while doing so. “We work hand-in-hand with the school administration. It’s a very fluent collaborative process and it works because you are still able to do this work without spending more money or time,” says Geyer.

“We have to be plugged-in to the inner workings of a large secondary school. We have to be plugged-into the sensitivities of the staff, teachers, and students. We have to be very empathetic.”

The school drama program and community theatre group both use the Genesis Theatre, which is part of the Delta Secondary complex. That building will be out of commission for over a year because of the extensive work needed to the foundation, flooring, walls, and roof.

“We have to work carefully with the school drama department to see how we can keep this program going without incurring an additional expense,” says Geyer. Community bookings have had to use other facilities during the upgrading.

“It’s all in the project phasing; it’s a matter of working around everything,” says Jeff Peters, project manager at Unitech Construction Management Ltd. “The auto shop can’t be closed at certain times, the cafeteria can’t be closed at certain times. If you take out a washroom, you have to make accommodations somewhere else.”

Peters, who has worked on several seismic upgrades with Geyer, says the biggest challenge was working while school was in session. “The school is occupied and functioning, and teachers are trying to teach kids and we have to respect that.”

While the crew takes full advantage of spring, summer and holiday breaks, that still won’t give them enough time to complete the project. “It means some afternoons, some Saturdays, go crazy before 9:00 a.m. and after 3:00 p.m.” But Peters says working in and around class schedules and special functions will help them get the project completed safely.

“After a few months, we’re almost invisible,” he says. “We’re just running around with our vests and the kids don’t even notice us. They’re resilient.”

And by 2017, the seismic upgrades made to Delta Secondary School will make the structure just as resilient as the students it holds. b