Flexible slab construction

The Goal

To build a multi-use residential building with integrated parking
The Broadstone SoBro building features three levels of parking and a podium slab, all of which were to be built from concrete. The parking garage was a flat slab design with 10 foot by 10 foot thickened concrete areas located over each column. To create this required an adaptable slab system that would not disrupt the progress of the works.

The Project

Summary:
The MEVA HN slab system was instrumental in building the new structure quickly thanks to the unique drophead, despite the complex slab design. 

Challenge:
The thickened areas of concrete within the otherwise-flat slabs needed a way to be built while still ensuring on-site efficiency. The project also required a safe working area to be provided around the slab edge for the workers to gain access when pouring the concrete.

The Solution

1. An adaptable slab system
   
   a) Superior flexibility
   The contractor chose to use the MEVA HN system for both the flat slab and thickened slab areas because of the flexibility of the MEVA HN drophead shoring system. This unique feature offered faster erection speeds and easier stripping due to the extra height of the drophead. Adapting the MEVA HN system to support the thickened slab areas was an easy transition by simply adding smaller primary beams and post shores to support the additional weight caused by the thickened area.

   b) Adaptable to different situations
   MEVA HN was also able to provide the working area around the outside of the slab. To achieve this, the primary beams were cantilevered outside of the existing slab edge from the floor below. The cantilever was achieved by securing the MD prop connector to the bottom center of each primary beam, which can then be cantilevered outside of the slab edge. The prop connector also provides an attachment point to secure the post-shore mid-span when supporting the primary beam. 

   In addition, the prop connector provides a point of connection for tying down the primary beam to prevent uplift from the wind when cantilevering the beams outside of the building. Lastly, the MEP aluminum shoring system was used along the slab edge to provide lateral bracing for the cantilevered beams.
    
   

2. Strong shoring solutions for unusual geometry
   Most of the elevated slab was designed to a height of 9 feet, but several areas located on the fourth level featured concrete slabs that extended outside the footprint of the floor below. As a result, shoring had to be erected from the ground up to the fourth level to support the concrete overhang.

   With the height reaching more than 20 feet, the MEVA32 aluminum shoring was selected since the frames are lightweight, easy to erect, and have a high 32-kip load capacity. In addition, the MEVA32 towers were able to be spaced further apart, which reduced the amount of shoring required and saved the contractor money.
    

3. Products which support construction efficiency
   As each floor of the parking garage was completed, the EuMax 350 post shores were installed to act as re-shoring. This helped support the newly poured slabs, while the slab formwork was able to be stripped and re-used on the next floor. Working this way enabled greater efficiency on site, as the next floor could be poured while the floor below continued to gain strength.  

The Outcome

The new Broadstone SoBro building was completed with the help of MEVA solutions. Lithko were so pleased with the efficiency of the system that they partnered with MEVA to supply formwork on additional projects in the area, including the Broadstone Nations and Broadstone One City developments. 

Featured Products

• MEVA HN slab formwork
• MEP shoring system 
• MEVA32 shoring towers

Client:
Lithko Contracting LLC

Developer:
Alliance Residential

Project:
Broadstone SoBro Multi-Use Residential Structure

Location:
Nashville, Tennessee

Engineering:
MEVA Formwork Systems, Inc.