Matrix was the prime civil and structural engineer for replacement of the Evans Avenue Bridge in Colorado Springs, CO. The existing bridge is located at the mouth of Cheyenne Canyon and was load posted due to age-related structural deficiencies. Matrix developed several alternatives and conducted a robust community outreach process to develop a design that could withstand the largest storm event possible while supporting a wider roadway. Due to site constraints, the bridge was designed to pass the 10-year storm event and allow the 100-year storm event to overtop the bridge while remaining in place. Additionally, because the bridge is in the City’s Cheyenne Canyon Park, the project required environmental clearance through the Federal Highway Administration.
The bridge was designed with prestressed, precast concrete slabs that provided the thinnest superstructure depth to increase the hydraulic opening. The precast slabs were set in place utilizing a crane, which allowed for expedited construction to decrease the amount of time the roadway was closed. Additionally, the bridge integrated stone from the old bridge rail. This stone was utilized as a façade for the new concrete barrier to match the old bridge’s aesthetic while providing a safer barrier. The reuse was determined a requirement of the surrounding community during the public engagement process and reduced the cost of materials.