RS&H recently picked up the American Council of Engineering Companies (ACEC) Illinois 2019 Engineering Excellence Award for the Chapel Hill Road Bridge rehabilitation project over the Fox River in McHenry County, Illinois. This award recognizes an engineering achievement that demonstrates a high degree of merit, is original and innovative, adds future value to the engineering profession and public perception, has economic and sustainable design considerations, demonstrates complexity, and exceeds owner/client needs.
The Chapel Hill Road Bridge over the Fox River is an eight span steel beam bridge that was constructed in 1938 and was nearing the end of its useful life. The bridge is a landmark in the Village of Johnsburg, and McHenry County was committed to preserving the historic structure.
But preserving the 81-year-old bridge presented several challenges. Due to leaking expansion joints in the bridge deck, two of the seven concrete piers had deteriorated significantly. The two piers, which had been renovated several times over the life of the bridge, had reached the point of being beyond repair.
An Alternative Solution
The bridge rehabilitation concepts proposed by previous studies involved supporting the structure on steel pile support frames installed in the river on either side of the deteriorated piers.
RS&H’s alternative solution avoided all work in the river, instead focusing on the reconstruction of the two deteriorated piers while leaving the bridge open to traffic. This design incorporated temporary steel supports that were anchored to the pier itself.
The creative design proposed and implemented by RS&H and McHenry County resolved a number of key challenges:
It completely eliminated the need for steel piles to be driven in the river.
The piers were reconstructed to the same lines as the existing piers, thereby preserving the historic legacy of this important structure.
The concept avoided work in the river by anchoring the support system directly to the piers, thus streamlining the permitting process, and protecting this important recreational resource.
Benefits on the Balance Sheet
The RS&H solution also proved cost-effective. While McHenry County had programmed $1.9 million for the project, the final cost was just $1.4 million.
RS&H Senior Bridge Group Leader John Ritchie, PE, SE, served as project manager for the RS&H team, which included James Shaw, PE, Joe Klenck, PE, Luke Martin, PE, SE, Arielle Malinowski, PE, and Mallory Weber, PE.