Trends Summer 2014 | Página 13

Solutions sought Variable soil conditions and rock layers proved to be another challenge for the team, according to Ivan Gualtero, Ayres’ lead structural designer. “Stability of the bridge was critical,” Gualtero said, adding that soils were soft on top with relatively shallow, hard, rocky layers beneath. This soil configuration, coupled with the project’s narrow footprint, complicated the foundation design. Engineers needed to reanalyze each footing for lateral stability as the foundation was being built, he said. But rather than establishing pile driving criteria for all piles based on the driving of test piles, as is customary, the structural and geotechnical engineers completed regular feedback loops, relaying encountered piledriving data back to the office so that designs for the remaining production piles could be refined. Still, the team once again rose to the challenge. “If a pile was driven out of tolerance and a redesign was necessary, (Ayres) was able to resolve it in a timely manner without any major changes to the overall project,” Quaid said. Norton praised the Ayres’ staff – Gualtero in particular – for their quick action and professionalism. “Ivan was always in the trenches with us,” Norton said. “Whenever there was a question or an issue, he was first to the site and very proactive.” A View to Admire The Courtney Campbell Causeway is designated as a Florida Scenic Highway. Designers of the new Courtney Campbell Multiuse Trail Bridge – just 90 feet away – took great care to see that the pedestrian bridge would not obstruct the views from the main highway. The pedestrian bridge features four strategically placed overlooks from which trail users can enjoy the stunning views of Old Tampa Bay. The observation points were not a project requirement but were included in the design to enhance the value. TRENDS │13