Morgan County Commission and the City of Decatur
Lee Builders Inc.
RISA-3D, RISAFloor, RISAFoundation
Concrete Frame, Concrete Walls, Elevated Concrete Slabs
The $11 million, 450-bed addition to the Morgan County Jail allows for the consolidation of all correction services under one roof. The new 3-story facility includes 29,000 sq. ft. of space including classrooms, sleeping areas, indoor/outdoor recreation areas and locker rooms. The main structural system for the building is reinforced concrete frames, with concrete shear walls and 2-way concrete floor slabs. Beyond the main structural system the project also presented some interesting challenges. One of the most difficult aspects was the poor soil conditions of the site. As a result, vibro stone columns (otherwise known as aggregate piers) were used to improve soil conditions. Additionally, the need for torsional reinforcement in the perimeter beams was needed due to the applied load created by the masonry and brick walls at the buildings exterior.
"The ability to establish design rules within RISA-3D for different types of structural elements, allowed us to maintain uniformity in beam and form sizes. This saved us time, money and allowed for easy modification of reinforcement when changes occurred."
— Jeff Hillman, PE, SECB
The conventional concrete system was chosen due to the heavy loading conditions, safety considerations and ability for the structural system to remain exposed. RISAFloor was utilized on the project to model, analyze and design the concrete floor slab and concrete floor beams due to its efficiency in modeling and ability to easily make changes. Once the gravity members were designed in RISAFloor, the framing and loads were transferred to RISA-3D for the design of the concrete shear walls and to RISAFoundation for the design of the concrete footing elements. The ability to work seamlessly between the three software’s allowed for integrated project delivery as well as accurate management of changes by the architect.
Images 1-3: Jeff Hillman