Upper Wacker Drive Viaduct, Chicago, IL

---

Comprehensive engineering services associated with distress caused to the historic concrete Upper Wacker Drive viaduct structure, across from the Merchandise Mart in downtown Chicago, by construction of the Deep Tunnel system under the Chicago River.  Involved emergency services to prevent the structure from collapsing and responding to over nine inches of differential settlement that occurred when a drop shaft of the deep tunnel system was de-watered overnight.  Included long term monitoring of the structure during the completion of the drop shaft and ultimately design and implementation of repairs to the damaged concrete viaduct service.   Work included cutting the columns that had settled, and subsequent jacking of the structure upward to recover some of the lost deformation.  This was followed by reconstruction of the columns and epoxy injection of numerous cracks in the structure.

---