Vista Tower

Vista Tower’s Unique Geometry and Formwork Needs:

No stranger to supertall structures, the city of Chicago soon will welcome its third tallest building – the Vista Tower. The 1,190 ft. high structure incorporates three inter-connected towers – an east, middle and west tower, with 47, 71 and 93 stories respectively...

Vista Tower’s unique design features a series of 19 alternating frustums, in which the towers angle outward nearly 5 ft.3 in. for 13 floors and then angle inward for the next 13 floors, creating a flowing design of rhythmic movement. Vista Tower’s distinctive geometry presents one of the most challenging aspects for the concrete subcontractor on the project, McHugh Concrete of Chicago. McHugh consulted with Doka early in the process to plan formwork solutions to meet the project’s demands. To form the building’s core structure, McHugh relies on Doka’s Super Climber SCP system. Four hydraulic cylinders lift the inside and outside forms from one level to the next. A platform anchored to the top of the forms holds a concrete placing boom which automatically lifts when the forms are raised. Workers can store rebar on the formwork, too, close to where ironworkers need it for placement. McHugh is using Doka’s SKE 50 and 100 self-climbing form systems for the shear-wall forms. However, the contractor is lifting the forms to the next level with building cranes instead of hydraulically for this project. The shear walls follow the building’s angle. Doka’s climbing system Xclimb 60 with protection screen system provides perimeter protection and a safe working climate for installing curtain walls and detailing. It also prevents tools and materials from accidentally falling to the ground and provides shelter from the wind at the highest level where concrete is being placed. It can be used to enclose floors for temporary heating.

The Challenge:
Vista Tower’s distinctive geometry presents one of the most challenging aspects, with a series of 19 alternating frustums, in which the towers angle outward nearly 5 ft. 3 in. for 13 floors and then angle inward for the next 13 floors.

The Solution:
To form the building’s core structure, McHugh relies on Doka’s Super Climber SCP system. Doka’s SKE 50 and 100 self-climbing form systems are used for the shear-wall forms. Both systems allow the option of lifting hydraulically or with building cranes. Xclimb with protection screen system provides perimeter protection.