Eliminating Malfunction from the Junction

$79 Million Rebuild of Downtown Interchange Nearing Completion

by Scott Judy

A team led by Granite Construction Co. of Tampa is moving into the final stages of one of Tampa's most prominent projects - the $79 million rebuild of "Malfunction Junction," the Interstate 4/I-275 Downtown Interchange.

Even though workers have had to deal with an extremely tight jobsite and significant issues related to keeping traffic moving through this busiest of Tampa interchanges, construction is on target to conclude on schedule by spring 2006.

The project is considered an operational improvement but includes the widening of both I-4 and I-275 to eight lanes. The operational improvements are the most critical, however, and address the interchange's well-known "malfunction."

John McShaffrey, public information officer for Earth Tech, a consultant to the Florida Department of Transportation and the owner's representative, described the project's goals.

"One of the key components is separating traffic that goes to downtown Tampa from the through traffic," he said. Whereas the old interchange featured numerous, last-minute weaves right in the middle of the structure, the new system will eliminate those movements via longer ramps and a single exit point for downtown traffic.

"Drivers will make that decision before they get into the heart of the junction," McShaffrey added. "Right now we have weaving problems with traffic on the mainline trying to get over to the (downtown) exit ramps, and then the ramp traffic coming on, and it's congested and a high potential for weaving accidents. The work we are doing is set to eliminate all of those weaving movements."

The project length is estimated at about 2.7 mi. and involves work on I-275 from the Hillsborough River north to Floribraska Avenue and on I-4 from east of 15th Street into the interchange.

In addition to mainline widening, Granite's contract includes the construction of eight new bridges, the widening of 18 existing bridges, plus the extension of the Ashley Drive entrance ramp from downtown onto I-275. Granite self-performed approximately 70 percent of the overall work.

Aggressive Start

Granite started work in October 2002 with roughly 60 people from day one, said Wayne Roberts, the company's project manager.

"We knew it was going to be a complex job," he said. "We had a really big engineering staff to begin with. We started out with a project manager, a project engineer and then eight field engineers. At our peak work force, we had three structures superintendents out here, a roadway superintendent, an equipment superintendent and a couple of assistants under them. So we were pretty loaded up."

Granite's contract included numerous incentive/disincentive clauses, including a detour rental spec that allowed as many as 60 detours off of the interstate.

Roberts said that soon after his firm was awarded the project it sought to rework the construction schedule to give itself a better opportunity to meet the associated milestones.

"The original construction sequence in the plans was good but did not meet the milestones that were set up in the contract," he added. "To have a shot at the milestones, we sort of redid the sequence. We knew the interchange was the key to the job, so that's the first place we went. We started working on drilled shafts and the substructure work for the new flyover and associated bridge widenings in this area."

Granite also employed a strategy of working in numerous places at once at the beginning of the job in order to keep moving.

"Early on, we tried to open up a lot of work areas so that when we did encounter a problem, we had some place to recover to," Roberts said. "It's not the most efficient way of building a job, of course, but especially when we had this carrot out in front of us, we were doing everything we could to build something."

Ben Molenaar, project engineer with PBS&J, Tampa, the project's construction engineering and inspection firm representing FDOT, added that Granite's aggressive approach started with its bid.

"Granite was very aggressive when they bid this job, especially when it came to the schedule," he said. "Originally the duration was set (by FDOT) at 1,500 days, and Granite bid it at 1,200 days. That was a big difference."

Tight Site

The project involved the purchase of only minimal new right-of-way and is mostly being built within the original footprint of the existing interchange.

"This project has tight working spaces and access problems for the contractor," McShaffrey said. "It's been challenging from the perspective of access and working with the traffic. Even at night it's pretty busy through there."

The construction of MSE walls along much of the project was impacted especially. For these, Granite erected the majority of the walls while placing the dirt over the wall as they were built or by tramming the material to the back of the panels with loaders.

The heart of the interchange was the project's critical path - and where the biggest problem occurred. As Granite was drilling pilot holes in preparation of constructing one of the endbents for the ramp from westbound I-4 to the downtown exit, it couldn't find sufficient limestone to support the drilled shaft.

"We'd just gotten the old flyover torn down and we were ready to start building this endbent, and we went out there and couldn't find any bottom," Roberts said. "We ended up having to redesign that endbent and do H piles. It was right on the critical path. That was a killer."

The necessary redesign took about six months to finalize but only stalled work completely for about a month. After that period, the engineer of record, Kisinger Campo & Associates of Tampa, and PBS&J were able to provide enough design information for Granite to get back to work.

"We were getting fed bits and pieces to keep going," Robert said. "It could have shut the job down completely, but they worked to keep us going."

Molenaar added, "Our main goal was to keep the designer of record on task and to make sure that any RFIs got responded to as quickly as possible."

Overall, Granite was able to progress steadily through this section of the job. Its approach here was to deconstruct the old structure in segments as it prepared to build the new segments. The company opened the new flyover in April 2004.

Meeting Milestones

Remaining milestones include a $10,000-per-day incentive to complete the project in less than 1,200 days, as well as a potential $1 million bonus for completing the widening of I-275 roads and ramps within the 1,200-day schedule. A separate $10,000-a-day incentive - for a maximum of $500,000 - is available for completion of the Ashley Street onramp within 200 days. That is due to the need to close this ramp entirely during its reconstruction.

The detour rental spec - a first-in-the-state provision - could deliver as much as another $900,000 to Granite. To date, the contractor had only used 12 of the 60 detours allowed for in the contract. McShaffrey said Granite will receive $15,000 for each unused detour, for a maximum of $900,000. A penalty in the same amount would be applied for any detours in excess of 60.

Molenaar said he was especially pleased with how the detour rental incentive had caused the contractor to re-think some of its planning.

"That's been a good thing because the contractor has gotten involved and been proactive in determining what activities were really needed," he said. "They were able to combine a lot of activities" to minimize detours.

"You're probably going to see more of it," Molenaar added.

Of course, the main milestone is final completion.

"When we got started, our goal was to (change) the name from 'Malfunction Junction' to 'Function Junction,'" Molenaar said. "I think once we get done, it will be much better."