Engineering Reports Highlight Iowa Building's Problems Before Partial Collapse
Jul 15, 2023
An apartment building partially collapsed in Davenport, Iowa, on May 28. Three residents of the six-story apartment building remained unaccounted for and might be stuck inside rubble that was too dangerous to search.
Photo by AP Photo/Erin Hooley
Months before a full-height section of a six-story apartment building in Davenport, Iowa, collapsed May 28, rendering the building dangerously unstable, a structural engineer advised owner Davenport Hotel LLC of an unexpected void, discovered during repairs to a damaged area of the perimeter brick wall. The building remains dangerously unstable, hampering efforts to search the debris for people still missing and feared dead.
The city has issued a public hazard notification to owner Davenport Hotel LLC and ordered "the immediate demolition of the structure." Davenport Hotel LLC and its registered agent, Andrew Wold, could not immediately be reached for comment.
City officials said they had hired contractor D.W. Zinser Commercial Demolition to assist with both recovery and demolition work.
The void appeared to have been created by the collapse of clay brick between the west wall and a layer of concrete masonry units (CMUs), the engineer, David Valliere of the Bettendorf, Iowa, firm Select Structural, wrote in a Feb. 28 report. The mass of collapsed material had then piled up and was pressing against the inside face of the wall, pushing it outward.
"This will soon cause a large panel of facade to also collapse, creating a safety problem and potentially destabilizing the upper areas of brick facade," Valliere wrote.
The void was not the first structural concern with the more-than-100-year-old building, which is an outdated masonry-and-steel structure with east-west beams, according to engineers who have worked on the repairs and collapse investigation. City records show more than 100 issues, which also include mostly nonstructural complaints, that drew the attention of city inspectors in the two years since the property changed hands. But the void was also not the last structural issue that would be discovered before the partial collapse.
The repairs apparently continued with additional work to fill the void with a second layer of CMUs, and a city inspector signed off on the work May 1. But when Valliere returned to the property a few weeks later, he found more problems. The brick around two former windows, and the area between them, was bulging outward and appeared "poised to fall," the engineer wrote. Workers stripped away drywall inside the first floor, which revealed windows had simply been bricked over, but never filled in or supported.
"This lack of bracing helps explain why the [wall] is currently about to topple outward," he wrote.
Valliere also found a section north of the bricked-up windows appeared to be losing some stability and causing deformation. Some interior light gauge steel and drywall was bowing and bulging as if a large downward force was acting on them, he wrote, suggesting that it may be due to an east-west beam bearing on the west wall. The engineer suggested filling the window spaces with reinforced CMUs and adding a steel column to support the east-west beam and alleviate the load from the wall.
Davenport Hotel received a permit from the city for the additional repairs May 24, records show. Just four days later, shortly before 5 p.m. on the Sunday of Memorial Day weekend, the upper five stories of a section of the building along the west wall where repairs had been underway dropped onto the first. Police say two people—Ryan Hitchcock and Daniel Prien—are still unaccounted for and feared dead. City officials say the men who are still unaccounted for "have a high probability of being home at the time of the collapse and their apartments were located in the collapse zone." The body of third missing person, Branden Colvin, has been recovered from the debris, the Associated Press reported.
Sandhaas said the debris pile is helping to hold up the remaining building. The city has brought in state rescue and recovery experts with cadaver dogs to assist in the search, and Fire Chief Mike Carlsten said they have also been taking advice from first responders from Miami-Dade County, Fla., who worked on the response to the 2021 Surfside condo collapse.
Records show that the building, at some point converted into about 80 apartments with ground-level retail, was originally known as the Davenport Hotel. Completed in 1907 at 324 Main Street, the Renaissance Revival design was "state of the art at the time" it was built, says Larry Sandhaas, a structural engineer with Shive-Hattery, which is investigating the cause using a LiDAR-equipped drone to create a digital model of the collapsed building.
The primary structure consists of steel beams spanning between perimeter bearing walls, Sandhaas says. That design later left the building brittle and nonredundant, and Sandhaas warned the building's condition was continuing to worsen after the partial collapse.
"The way the building was built, with short pieces of steel depending upon exterior brick for stability, that's not how you build a modern building," Sandhaas said.
The Davenport Hotel building was listed on the National Register of Historic Places in the 1980s. The property then changed hands several times, with Davenport Hotel LLC purchasing it for just under $4.2 million in June 2021, county property records show.
City records show questions about the building's structure go back even further, to at least 2020, when an inspector issued violations for damage to the exterior walls and ordered the owner to obtain a structural engineering report.
The next year, one of the residents complained about a door on the west side of the building that was difficult to open, and he questioned if the building was structurally sound. An inspector's photos from the time show vertical cracks several feet tall in a unit's drywall.
The city received dozens more complaints about the property, but most were related to issues like trash or utility outages, records show. In March, the city cited Wold for 19 trash violations between June 2022 and March 2023. After Wold failed to show up for court, a judge ordered him to pay $4,500 plus court costs.
When repairs were getting underway for the west-wall exterior brick earlier this year, the engineers recommended a plan to replace a section of the wall in segments to minimize the time when the west side of the building would be supported by shoring. There was, at the time, no "imminent threat" to the building or its residents, but Valliere warned that there would be risks involved in the work.
"It is further emphasized that the full 12 ft length of wall to be replaced is not demolished all at once," he wrote. "There are many unknown factors in the construction and stability of a 100-year-old masonry structure. As always, there is inherent risk to altering an existing masonry structure which is showing signs of deterioration. The purpose of the staged and incremental demolition and reconstruction of wall segments is to minimize the risk of local structural failures."
After discovering the additional issues later in February, emails provided by Davenport officials show that Valliere wrote that the contractor, Bi-State Masonry, Rock Island, Ill., was following his design and "doing a good job from what I can see." City inspector photos show progress on the work, with a fresh interior CMU layer and brick wall by the start of May.
It is not clear whether Bi-State remained the contractor through the whole project. A city inspector noted that, as of the week of March 1, the contractor "was off the jobsite because the owner did not agree to their change order for installing brick outside." The contractor did not immediately return calls.
Photos from an inspection on May 25 show parts of the wall cracking and bulging. Wood braces had been placed against the wall with anchor cleats into the pavement. The bricked-over hollow window frames had been discovered, but it's not clear who was working on the repairs. Unlike the permit for the earlier work, this one lists the contractor as "owner," and a job cost of $3,000, compared to $39,746 for the earlier repairs, which still list Bi-State in city records.
Wold Cited Again
The city has again cited Wold, the owner, for allegedly violating the city code requiring the maintenance of buildings in safe, sanitary and structurally sound condition, court records show. The citation carries a maximum penalty of $300.
Some Davenport residents have criticized the response and moves to demolish the building while there are still some people missing. Protestors have gathered near the fenced perimeter around the building, chanting "find them first."
The way the collapse occurred reduces the chances of a void large enough for a human to survive, Sandhaas said.
Residents’ scrutiny has also focused on Wold. The Quad City Times reported that contractor Ryan Shaffer of Moline, Ill.-based R.A. Masonry, said he’d given Wold a quote for the repairs of about $50,000. He told the newspaper that Wold "wanted to cut the cost by cutting out the shoring and supporting of the building." The contractor did not immediately return calls.
Some residents criticized the penalty levied against Wold as too minor, though city officials say the legal action is a formality needed to ensure the owner cannot transfer the property to avoid a lien once demolition and other costs are known.
This story has been updated with new information.
Once 'State of the Art' Shoring and Repairs Wold Cited Again