Structural Design Alternative
Since the Oklahoma University Children's Medical Office Building is constructed using a two way concrete system, the construction process is extremely long to allow the concrete to cure. This adds additional costs to the project, making the job more expensive. Concrete is a labor intensive material meaning that the installation requires many skilled labors to construct the forms, set the reinforcement, and leveling the concrete. The high amount of labor adds to the overall project costs, making concrete a relatively expensive material. The proposed thesis will be a redesign of the building structure using steel. The gravity system will consist of a composite steel system with composite decking. The lateral system will consist of steel braced frames located at existing shear wall locations. A redesign using steel instead of concrete should reduce construction time resulting in lower costs to the owner. Steel in comparison with concrete is not as labor intensive. Steel does not require the level of skilled labor as concrete does to install unless complicated field welds are used. As part of the proposal, bolted or factory welded connections will be used where ever possible. These connections will be used to speed up the construction process and reduce the costs as field welds become expensive and time consuming due to the skilled labor and precision of the weld.
Cost and Schedule Analysis
Due to the proposed change of material, the first proposed breadth is a detailed cost analysis and schedule impacts of the proposed steel system. Since the material will be changed from concrete to steel, the costs for labor should decrease reducing the overall project costs. The construction time will be decreased due to the material change. The time it takes for the concrete to cure dramatically increases construction times. With using steel as the structural material, these times can be greatly reduced saving money.
Green Roof Addition
The second breadth will be the addition of an extensive green roof. With the addition of the green roof, this will potentially reduce the heat island effect of the building. The green roof also has the potential to clean the air by filtering pollutants such as carbon dioxide. This will potentially reduce the heating and cooling cost of the building. An extensive green roof will be used instead of an intensive green roof due to the lower initial costs, lower maintenance costs, and lower roof loads. Research will be conducted to use local plants to reduce the amount of maintenance. The plants that are typically used for an extensive green roof are hardy perennials that can withstand wind and extreme temperature fluctuations. Sedums are typically used because they are drought resistant and require little maintenance. Other components of the green roof must also be researched to provide a stable area for growing the plants without causing damage to the building such as water leaks. These areas include the growing medium, a filter membrane, a drainage layer, a root barrier, and a waterproofing membrane. The down side of the green roof addition will be higher initial costs and additional loads which will have to be accounted in the load calculations.