Innovative Piling Solutions tackled a project that was tight on both time and space, devising a customized piling solution that met construction deadlines despite the intervention of Old Man Winter
Time. It’s the one ingredient that was extremely scarce during the foundation construction phase for the University of Saskatchewan’s cutting edge Collaborative Science Research Building (CSRB).
In fact, the timeline for constructing the foundation of the $63 million, 91,000-square-foot research facility in the fall of 2016 was so tight that construction meetings were held every 12 hours to ensure the work stayed on track.
Not only did pile driving need to be completed before the university’s final exams started on Dec. 8, 2016, but work had to be done within a limited daily window that respected community and university noise by-laws.
Add to that a Saskatchewan cold snap that delivered three feet of snow on freshly excavated soil within one week – and space restrictions that necessitated squeezing up to four pieces of equipment into a 15×15-foot area – and it’s no wonder that Banain Cote, vice president of operations at Martensville, Sask.-based Innovative Piling Solutions (IPS), called the CSRB project one of the province’s most complex deep foundation projects.
“Not only was it a combination of earth retention and deep foundations, it was trying to make the schedule work. Not many projects have required that level of scheduling intensity,” said Cote during a recent interview.
The original plan for the five-storey facility (four above ground, one below) called for a straight shaft and belled drilled concrete pile foundation. IPS and its engineering team knew there was water infiltration at the site at a depth of about 15 metres and had concerns about the water interfering with the formation of the concrete bells.
“When we met with the construction manager, Wright Construction, they wanted to pick our brain about the best pile type,” said Cote. “We had to come up with an alternative that either saved money or was faster, and we did both.
“Our main concern was the schedule. This project had to be in commission in 18 months, and piling had to be done prior to finals at the university. So we switched from drilled cast-in-place concrete piles and proposed driven steel pipe piles and helical steel screwpiles for the structural piling and switched the CFA secant wall to driven H-pile soldier piles with wood lagging for the earth retention.”
IPS arrived on site on Nov. 3, with a deadline to complete the piling phase of the project by Dec. 8. In total, the company fielded 19 employees from job start to finish.
The scope of IPS’ involvement included installation of the shoring wall – with 18 feet of earth to retain, the structural piling itself and the excavation and construction of the pile caps, which were 10x10x3 feet thick. Before the company could begin its work, an overhead walkway had to be removed to allow access to the site down a 10-foot-wide ramp.
In total, 21 truckloads of pipe and H-beam had to be craned in to a site where a half-tonne pickup truck could barely fit. The list of materials for the job included 160 driven 16-inch pipe, each 60-feet long; 125 driven W310x79 50-foot-long H-piles; and 89 seven-inch by 30-feet long with a 24-inch helix helical steel screw piles.
Cote says that to make the schedule work, IPS had to install the structural driven pipe piles from grade.
“They didn’t want to excavate down until we had the piles in the ground. We fashioned a chaser that was able to drive the pile 16 feet below grade. We were able to drive every pile to within three inches of final depth.”
Originally, IPS had proposed a schedule that allowed for pile driving at night, so the work didn’t disturb classes. However, a permit dispute meant they subsequently had to make workday adjustments due to noise by-laws.
“When you’re driving piles at night, you can hear it clear across the city,” said Cote. “So we got shut down the second night we were on site. From then on, we started at 5 p.m. and had to finish at 10 p.m. On the weekends, we had to put in 16-hour days across four weekends to make up that time.
“We were supposed to be finished on Dec. 8 and we were rigging out the Junttan on Dec. 7 – the pile driving was finished a day before the university’s exam deadline,” said Cote.
“ We were supposed to be finished on Dec. 8 and we were rigging out the Junttan on Dec. 7 – the pile driving was finished a day before the university’s exam deadline.”
– Banine Cote, Innovative Piling Solutions
IPS returned to the site in early January 2017 to excavate and build the pile caps, working alongside Globe Excavating, 14North Construction and Wright Construction as they excavated the main foundation and built the walls.
“Our scope didn’t really stop at the pile driving itself. We took this on as more of a general contractor for the foundation,” said Cote. “We had sub-contractors of our own. We had 14North Construction Ltd. doing steel reinforcement and pile cap building; we did our own excavating and Globe Excavating did tailings removal for us; and we worked in conjunction with Wright to make sure their walls were stood on piles that had been infilled correctly. P. Machibroda Engineering Ltd. performed 16 Pile Driving Analyzer (PDA) tests for dynamic load testing and Topping Engineering did a lot of the work for the driven pipe piles and earth retention.”
Given the physical restraints of the job site, it was a challenge getting equipment in and out. The project entailed the use of a Junttan PMX22 tracked pile driver rented from HPS Pile Driving & Drilling Services in Edmonton, a Texoma 800 drilling rig and a Texoma 600 drilling rig that were used to pre-drill holes for the driven pipe piles, a Hitachi 270 screw pile unit, Bobcat T750 and S650 machines, a SkyTrak zoom boom, a Bobcat E85 mini excavator and a CAT loader, all of which were IPS-owned.
As the largest piling company in Saskatchewan, IPS specializes in taking a creative approach to the most challenging tasks – a skill that certainly came in handy on the university’s CSRB project.
“It wasn’t a typical boxed project where they give you the drawings and then you price it and do the job,” said Cote. “I think the hardest part of this project was swinging from Saskatchewan fall to full-blown winter. On the same job we went from 20 degrees Celsius to -45 degrees Celsius (68 degrees Fahrenheit to -49 degrees Fahrenheit), all while trying to work 24 hours a day to keep driving the schedule. We had eight pile caps that had to be dug four or five feet in the ground, and we had three feet of frost on excavated soil within a week. It was a bad cold snap.
“We stuck through it the whole time. In the end, the university was very pleased with how the job came together and how quickly the schedule moved along.” 