Project Owner

F.H. Paschen


Omega III, LLC

Services Provided

Structural Engineering
Demolition Analysis and Procedure


Aurora, IL

Year of Construction


Demolition of IL Tollway Bridge #801, Deerpath Rd over I-88


HBM Engineering Group, LLC was contracted by Omega III, LLC to provide structural engineering services for the demolition of ISTHA Bridge #801, located over I-88 near Batavia, IL. This demolition is part of the reconstruction project led by FH Paschen.

Bridge Data:

  • Length: 240’-4½”
  • Width: 30-4”
  • Number of Spans: 4
  • Skew: 24.6 degrees
  • Number of Beams: 4
  • Slab Thickness: 8 inches


HBM’s Scope:

  • Structural Engineering
  • Demolition Analysis and Procedure

The project involves the demolition of the existing bridge structure, including the superstructure, substructure, and crash walls. The work is divided into two phases.

Phase I – Demolition Procedure:

  1. General: Identify utilities, implement lane closures, and ensure safety.
  2. Parapet Removal (Spans 2 & 3): Use a bridge box with excavators to remove parapet sections systematically.
  3. Deck Removal – Slabbing (Spans 2 & 3): Employ transverse saw-cuts and excavators to lift and remove deck segments.
  4. Deck, Parapet, & Beam Removal – Wrecked-in-Place (Spans 1 & 4): Utilize an excavator with a hammer attachment to demolish parapet and deck, and cut beams. Preserve a minimum of 1’-0” concrete for stability.
  5. Substructure – Abutment & Pier Removal: Demolish abutments and piers with excavators, ensuring proper processing for offsite recycling.

Phase II – Demolition Procedure:

  1. Substructure – Crashwall Removal: Wreck existing crash walls using excavators with hammer attachments. Demolish precast concrete piles below grade.

Equipment List:

  1. 56k Excavator
  2. 87k Excavator
  3. 118k Excavator
  4. 40k Loader
  5. 8k Skid Steer
  6. Grove GMK6350 (on ground)

Structural Analysis: The existing structure was analyzed using Bentley Open Bridge Designer to ensure it can withstand the demolition loads. Calculations considered the live loads of demolition equipment and demonstrated that the bridge capacity is adequate.

All recommendations for phased demolition procedures, safety measures, and equipment specifications are provided to ensure a successful and secure demolition process.