As the troubles became apparent in 2016 and 2017, the flawed slabs threatened costly delays in enclosing the tower floors. A Pennsylvania state court judge ruled in October that Tutor Perini Building Co. breached its contract with the owner, Chestlen Development, and was "obstructing and intentionally concealing critical information from Chestlen about the true cause and extent of the floor issues."

The contractor, facing a claim from the developer for $155 million, now seeks tens of millions of dollars from its main subcontractor for the building frame, Thomas P. Carney Inc. That company began to camber floor slabs to prevent excessive deflections, according to court records reviewed by ENR. But according to deposition testimony of its president, Bob Carney, the firm did so under stressed and confused circumstances and made no record of what was done.

The project team's overall result was a building that received its certificate of occupancy three years late, in 2021, with a tangle of nearly 30 lawsuits or liens that have encompassed the owner, prime contractor, key subcontractors, the architect, engineer-of-record and two sureties. As Judge James Crumlish III of the Philadelphia County Court of Common Pleas next month begins considering damage assessments, an important question remains: how could crucial aspects of slab and window walls have gone uncoordinated on what is said to be the largest concrete-framed tall building in the city?

In a familiar pattern from countless prior construction projects gone awry, the owner and designers, on one hand, and the contractors, on the other, still are pointing fingers at each other over who should have been responsible for cambering plans and slab edge details.

While the judge sharply criticized Tutor Perini for its work and actions on the estimated $280-million project, he also ruled that Carney breached its contract with Tutor Perini and was ultimately responsible.

Tutor Perini officials could not be reached for comment on the case, but the company has argued that poor design work was behind the trouble, and that the developer improperly took advantage of the situation by withholding payments. Tutor Perini also blames Carney for contract breach.

The Langhorne, Pa.-based subcontractor is pursuing its own separate civil court charges against Chestlen, related entities, project architect Cope Linder Architects (now known as Nelson Worldwide) and the Philadelphia, Pa.-based structural engineer-of-record, O'Donnell & Naccarato. The claims and liens are consolidated into one case. Carney says in a statement that it "executed this project with a team of highly qualified professionals who met all contractual requirements and quality control standards. We stand by the qualifications and dedication of our team."

A page from a report prepared for Chestlen Development by owner's forensic consultant HKA shows one of the facade and window problems related to concrete slab defects. The report claims to have documented $155 million in damages, including liquidated damages of $35,000 a day for more than 1,000 days.

Starting in 2015, Tutor Perini was working under a guaranteed maximum price contract requiring substantial completion in 1,017 days with liquidated damages of $35,000 per day.

In the early stages, project work progressed normally. Carney framed the building podium and completed a record-breaking slab placement with the largest continuous pour in Philadelphia's history. The firm features the project concrete work, performed under separate podium and tower contracts of $23 million and $31 million, on its website.

A tangle of about 30 lawsuits resulted from disputes over the construction of the 51-story W/Element Hotel in Philadelphia.

Photo:TastyPoutine under CC 4.0 via Wikimedia Commons

But the seeds of trouble may have been planted early in the project planning.

During a long deposition taken in 2023, Chestlen's attorney probed Bob Carney about a commitment his company allegedly made to use a more experienced tall concrete building contractor to prepare shoring plans. Carney said simply that the other contractor, despite once being interested in participating, eventually "didn't want to do it." 

When another engineering firm was engaged to prepare shoring and re-shoring plans, according to Crumlish, the plans required using two sets of formwork on the project "on a "four-day cycle for the floor-to-floor pouring" of slabs.

The problems in the upper portion of the structure became clear with arrival on site of Chicago-based Ventana, an experienced national window wall contractor. Rebar at slab edges was discovered where anchorages needed to be drilled. Elevation variances meant windows could not be built that would fit snugly and function properly. Ventana brought in a consultant who found many problems with the slabs.

Tutor Perini engaged its own consultant, which told the contractor that Carney was not using the designed forms and reshoring system created for the project, according to Crumlish's narrative of events.

The contractors had placed floor slabs with rebar at edge locations that made it impossible for Ventana to perform its work without changing the design, ordering more aluminum and additional anchor bolts.

Even after the concrete problems were known, Tutor Perini and Carney continued placing floor slabs that failed to follow shoring and reshoring plans, Crumlish wrote. After problems deepened and work fell behind, the developer began withholding payments from Tutor Perini and the contractor did the same with some key subcontractors. The first lawsuit was filed in 2019.

Determining who was responsible for floor slab cambering—as opposed to simply shoring or reshoring—became a key project issue once the problems were apparent.

Who Is Responsible for Cambering?

According to court records, subcontractor Thomas Carney said that camber—deliberately deflecting a slab or structural element upward in anticipation of downward deflection—is the bailiwick of the designers.

Two engineers from the American Society of Concrete Contractors provided some perspective on the issue in 2019. "Formwork camber requirements for cast-in-place reinforced concrete are far less common today than in the past, but when bidding a job that requires forms to be cambered, concrete contractors should be cautious," they warned in an article on the website forconstructionrpros.com. "According to American Concrete Institute's Formwork for Concrete, contractors are expected to '…set and maintain forms so as to ensure completed work to the camber specified by the engineer/architect, within the tolerance limits specified."

The institute guidance "does not have a tolerance on camber and setting reasonable tolerance limits is not an easy task for the engineer/architect," they wrote.

In sitting for a long deposition by Chestlen attorney Peter Sheridan in Lansdale, Pa., on Nov. 13, 2023, Bob Carney said his company tried to fix the problems on its own. 

During the deposition, the attorney repeatedly pressed Carney about how the eventual decision by his firm to camber some of the hotel's upper floors was made and how the work was done.

When work reached around the 18th floor, Carney recalled, "we had seen these deflections, we sought information from structural engineer O'Donnell and Naccarato and "Tutor Perini asked [it] that question, and [firm members] said, 'camber is the responsibility of the contractor.'"

Both Tutor Perini and Carney claim in the various civil lawsuits that the designers' work product, or "instruments of service," were deficient and contained errors and omissions that explain much of what went wrong on the project.

In court fillings, O'Donnell & Naccarato strongly denies the accusation that design flaws or omissions are to blame and last year requested a jury rather than a bench trial.

Engineer: Construction Team Flopped

O'Donnell & Naccarato argued that Carney and others on the construction team "failed to adhere to the structural specifications and "otherwise improperly performed their work, resulting in unexpected, excessive deflection of concrete slabs."

With responsibility for what was happening on the project unresolved in 2017 or 2018, Bob Carney said, "'We took it on ourselves to say, 'where can we add camber and how much can we add in order to reduce these deflections?' We would go around [the structure], and in many locations we would take a look at the floors and where the deflections were, and we would go through and add camber."

In 2019, the subcontractor sent an invoice to Tutor Perini for the cost of additional "camber in the shore decks from levels 18 to 50."

Attorney Sheridan asked Carney at the deposition to explain the criteria used to "improve the situation in the installation of camber"?"

He asked: "Where is that written down so that I can see it and understand it now?"

Carney replied: "I think I had said earlier we didn't write anything down, and we didn't record anything." He added, "We would go to the floor below or the floors below and see where our larger deflections were. Then we would go back up top, and we would put camber in areas where we thought we could improve the situation."

The window installation contractor and Tutor Perini "were all aware of what was going on as far as the deflection around these perimeters," Carney continued. "So we were up top and 'saying, well we don't want to continue with it. Let's see what we can do to try to make it better.'"

This story was updated Dec. 19 to reflect the fact that there were separate podium and tower concrete frame subcontracts with Thomas P. Carney Inc. of $23 million and $31 million dollars.