Insufficient shoring and a rushed schedule could be the cause of a 10-story parking garage collapse on Oct. 31 that killed four construction workers and wounded 21, according to some of the workers. A federal inquiry committee has been organized to examine why the accident occurred.
At the parking deck under construction at the Tropicana Hotel and Casino in Atlantic City, workers were rushing to complete the project because of harsh weather last winter. According to John Pietrosante Jr., a worker on the site, instead of pouring one floor of concrete every three weeks, the crew was being pushed to do a floor a week.
The new parking garage was being built using filigree wide-slab construction, in which factory-made flooring sections up to 70 feet long are lowered into the building, where they are temporarily supported by the pole shores. A layer of concrete is then poured, making a composite floor structure that is about 10 inches thick. In this type of construction, the pole shores are extremely important.
If there is an insufficient number or the posts are not of the proper capacity, they could start to buckle, threatening the integrity of the floor.
Several of the construction workers had noticed some unusual signs, such as the poll shores bending under the weight of the concrete. They also said they built floors when the concrete in the floors below them was “too green,” or not fully hardened. When Peitrosante and a fellow worker asked supervisors about the bent poles and the quick cracking in the floor, supports and beams, they were told that there was nothing to be concerned about.
On the morning of Oct. 31, workers were on top of the seventh and eighth floors of the garage using a hose spewing concrete to pour the next floor. Then there was a rumble, a loud boom and one slab pancaked onto the slab below. The top five levels collapsed, killing three workers instantly. The fourth worker died at the hospital. For the workers who survived, many were left trapped or hanging onto standing columns or poll shores. Most of the 300 workers walked away from the site, and emergency personnel and a crane bucket rescued the workers trapped on the top of the structure.
The parking deck was scheduled to be demolished last week, but demolition was stopped by the federal investigation. The two companies in charge of the project, Keating Building Corporation of Philadelphia, and Fabi Construction of Egg Harbor Township, N.J., have faced OSHA and federal fines in the past for accidents on other Tropicana Hotel projects.