Concrete Enlargements
Capacity added to the member itself, for the structures with nowhere to put a new column.
When the load a structure has to carry goes up, the conventional answer is a new column or a new support frame — and in a garage, a plant or an occupied commercial building that costs parking spaces, headroom or floor area that the owner cannot give up. Section enlargement takes the other route. Additional reinforcing steel is anchored into the existing member, the section is enlarged in concrete or shotcrete, and the member that is already there carries the new load.
Where a new column is not an option
Where traditional support columns would be added but create loss of parking or operational space within a garage or a commercial structure, Delta provides an alternate solution. Enlargement is rarely the whole answer on its own: new distribution ribs tie three or more beams together where load has to be shared, and externally bonded composite systems take the members that need strength rather than stiffness. Delta’s design resources are used to combine them, so the structure gains capacity without the client losing operating space.
Capacity added to the structure that is already there, not to the space around it.
- 01
Column Enlargement
Axial and flexural capacity added to an existing column, with the enlarged section confined and tied back into the original.
- 02
Beam and Joist Enlargement
New distribution ribs and section enlargement to boost the stiffness and capacity of beams and joists.
- 03
Slab Enlargement
Depth and reinforcement added to an elevated or on-grade slab where the span, the load or the use has changed.
- 04
Pedestals and Foundations
Equipment foundation preparation and grouting, metallic base plate, full bed grout, chocks, and anchor bolt repair or replacement.
- 05
Corroded or Distressed Members
Rehabilitate and strengthen to meet or exceed the strength values intended for the original structural member.
- 06
Combined Systems
Enlargement designed alongside near surface mounted FRP bars and externally bonded carbon fiber, as one system.
Where it has been used
The Sky Bridge carrying pedestrian traffic and major utilities over Worth Street to the Charles F. Sammons Cancer Center in Dallas is one of them. Its south end lands on an underground garage that had to stay in continuous use, and the reinforcement could not cost parking spaces or headroom, or force the rerouting of mechanical, electrical and plumbing systems. Analysis showed the beams were short on shear but held reserve flexural capacity that could be enhanced. Concrete distribution ribs were installed to connect three or more beams, section enlargement was used for more capacity, and carbon fiber strengthened the members that did not need additional stiffness. The project was completed on time and on budget, and won ICRI’s Award of Excellence for Repair of Low Rise Structures.
Design and installation
This is done after our design team has worked closely with the project Engineer of Record to find a design build solution to meet their needs. The design is sealed through independent structural engineers, and the work is installed by Delta’s own crews rather than subcontracted labour.
