KANSAS CITY, Mo. — A bridge safety expert told the KSHB 41 I-Team that the pouring of ready-mix concrete is the “most critical” part of the deadly Clay County bridge collapse project.
One person died and three others were injured Wednesday when Shady Grove Bridge, which crosses Carroll Creek at Northeast 148th Street near Kearney, collapsed while under construction.
Timothy Galarnyk, a construction forensic investigator, put himself in the shoes of OSHA investigators, who are working to find the cause.
“That means I might have to go back a couple of weeks to look at the temporary design for the temporary falsework,” he said.
Galarnyk said falsework is the temporary support built to withstand poured ready-mix concrete. Once that mixture solidifies and strengthens, then crews can remove the falsework.
When it’s poured, that mixture is wet and heavy.
"It has no strength at all,” he said. “That is the most critical part of pouring ready-mix.”
The planning process for such slab-span bridges is thorough, according to Galarnyk.
"That plan has to be designed by an engineer and submitted,” he said.
Additionally, Galarynk noted an engineer oversees the pouring of the ready-mix along with the curing, or drying, process.
Lehman Construction was hired to demolish the existing wood-and-metal pony truss bridge and build a modern steel-girder “superstructure slab bridge,” including adjustments to the approaching roadways and incidental work as required.
Clay County said in a statement that it also contracted with WSP Engineering to “both design the bridge and to perform inspections at all critical points of the bridge completion process."