After proper research is conducted on optimal trusses, our team began sketching possible designs. This process is to gather the most feasible ideas before moving into simple modeling. The two sketches displayed to the right are examples of the many possible designs for this project's 1:10 scaled prototype bridge.
Preliminary modeling was conducted in Risa2D in order to evaluate the structural efficiency of the main vertical trusses found on the side panels of the bridge. The three truss configurations with the least deflection in the modeling were labeled as Option 1, Option 2, and Option 3.
Our team constructed a decision matrix with these options in mind. This decision matrix had a total of four categories, including: constructability, structural efficiency, economy, and aesthetics. The scoring ranged from 1-10, with ten being the best possible score. The results can be seen below.
The software used to model our steel bridge design was STAAD.Pro 2024. The team used this software to create an analytical model reflecting our chosen member and connection selections. The model followed the constraints set by the American Society of Civil Engineers (ASCE) and the American Institute of Steel Construction (AISC). The load cases were modeled and tested using our bridge design to determine the predicted deflections to ensure there would not be any failures.
The bridge consists of two connections: bolted and welded. These connections have their own separate equations and outcomes, so our team used the American Society of Civil Engineers (ASCE) Steel Manual in order to complete the needed calculations. Our design has redundancy, which allows for less calculations due to the repeated connection types.
The cost of construction after the project was complete was recorded to be ----. The staffing, supplies, materials, subcontracting, and traveling have their costs detailed in the following table:
