KA Block Update- August/September 2016
Embeds
Work continued on the KA Block despite one of the wettest summers on record. The project remained on schedule as the team erected a second tower crane, poured the future first floor of the new headquarters building and began structural-steel erection.
Project Manager Chad Rempe and Project Superintendent Terry Coleman shared the following update.
What Were the August Construction Highlights?
Chad Rempe: When weather allowed, the team completed four of 15 structural slabs. The most notable was Level 1 of the KA office building, completed August 31, 2016.
How Did the Cranes Work Safely Together?
Terry Coleman: Three cranes worked on the site, including two tower cranes and a smaller mobile crane supporting structural-steel erection.
The crane teams used an open radio channel to communicate clearly and coordinate load-lift timing. The cranes operated at different heights, which prevented their jibs from interfering with one another.
What Was the Structural-Steel Erection Schedule?
Coleman: Steel erection began immediately after Labor Day. After the first day, weather conditions were ideal, with cool and clear conditions for the following week.
Eighteen ironworkers were on-site, and the work was progressing on schedule for completion during the first week of October. The final beam was being painted and scheduled to be available for signing at the Circle Pines Yard near the end of September.
Point cloud created to document embedded items before the concrete pour.
How Much Steel Was Used?
Coleman: The headquarters structure included:
- 543 tons of steel in columns and beams
- 1,031 squares of metal decking
- A beam measuring 33 inches tall and 35 feet long, weighing 5,300 pounds
Where Was the Steel Produced?
Coleman: American Structural Metals in Somerset, Wisconsin, produced the steel.
Was Just-in-Time Delivery Used?
Embeds welded to the pour stop.
Coleman: Steel arrived daily in the order required for erection, directly from the supplier.
To reduce field welding, precast embeds were attached to pour stops at the factory. This required more coordination during steel fabrication but reduced the amount of welding required at elevated work areas.
How Were Materials Staged?
Coleman: Each truckload was unloaded on the ground beside the crane, and steel pieces were erected between truck deliveries.
A semi-trailer load of spray-applied fireproofing was scheduled to arrive as needed, limiting the need to move materials around the site. When fireproofing began, the project would have a crane, concrete pump and deliveries operating along Eighth Street.
Smaller deliveries that could be lifted directly into place helped limit early forklift activity
Laser scanning documented the headquarters floor slab before the concrete pour.
What Was Scheduled for September?
Coleman: Vertical construction of both the KA office building and residential tower began in September.
Structural-steel erection for the office building began the week of September 5, 2016. Concrete columns and structural slabs for the residential tower began the week of September 19, 2016.
What Was Required to Pour the Headquarters Floor?
Coleman: Pouring the headquarters floor required detailed coordination of embedded items cast into the slab, including:
- Structural-steel column anchor bolts
- Steel stair and miscellaneous-metal embeds
- Precast support embeds
- Granite support embeds
- Curtain wall support embeds
- Sheet-pile foundation-wall connection embeds
- Elevator divider-beam embeds
- Power and data floor-box layout
Point cloud created to document embedded items before the concrete pour.Laser scanning documented the headquarters floor slab before the concrete pour.
KA and affected subcontractors relied on 3D modeling to confirm embedded items were free of conflicts and correctly located. The KA virtual design and construction team worked closely with Project Superintendent Al Zaffke to scan the entire slab before the pour, documenting embed locations for future reference.
Learn more about the start of KA Block headquarters and residential-tower construction, historic features in the new headquarters, BIM and VDC services and a tower-crane operator’s perspective.
CATEGORY: Construction