Catalyst Cracker Unit No. 1 – Inspection, Analysis, and Retrofit Design ConocoPhillips Wood River Refinery | Industry
Juneau Associates, Inc. P.C. was recently selected to perform structural engineering services for Conoco Phillips Catalyst Cracking Unit No. 1 located within the Wood River Refinery in Wood River, Illinois. The Catalyst Cracking Unit No. 1 is a 16-story structure with a total height of 209 feet 3 inches. The ground footprint area of the structure is about 8826 square feet.
Engineering task items were performed by Juneau included the Inspection, Analysis, and the Retrofit of the overall structure:
Inspection Phase
- Prepared structural plans, including plan views, section views, and details for each of the 16 floors of the unit. These plans were based on the original 1940’s as built drawings and on structure plan revisions that were available.
- Inspected and evaluated the overall structure, including field verifying the as-built plans and noting any deviations to the plans, inspecting the primary structural members, inspecting the secondary structural members, and inspecting the decks, rails, and stairs.
- Documented all structural deficiencies noted during the inspection. This documentation was prepared in an overall spreadsheet format, and also prepared utilizing Autocad drawings where the structural members with deficiencies were highlighted and the different structural deficiencies types were shown in different colors.
- Prepared a Summary Report to list our Findings and our Recommendations for repairing the structural deficiencies with the goal of extending the overall life of this structure.
Analysis Phase
- Perform a structural analysis of the steel frame CCU-1 Unit which consists of over 7000 steel beams, columns, diagonal braces, and secondary members. This structural analysis utilized Bentley System’s STAAD.Pro software (V8) based on loadings defined in ASCE-7-2005. These loads included dead loads, live loads, windloads, snow loads, rain loads, ice loads, and seismic loads.
- Prepare a Report with the Analysis results including a General Description of the Structure, the Analysis Results, by structural member, for each load and or loading combination.
- Juneau summarized our finding in the Recommendations Section, which identified those structural members that were overstressed, the load or loading combination that produced the overstress, and whether the member was either a primary member of secondary member. In addition, we recommended whether the structural member should be repaired or replaced, and prioritized this repair or replacement.
Retrofit Design Phase
- Performed the structure design to replace or strengthen both primary and secondary structural members of the CCU-1 Unit that were determined from the Analysis Phase to be overstressed. The overstressed members consisted of 135 primary members and 229 secondary members.
- Prepare Construction Documents for the recommended structural repairs and replacements.
- The design and details for the structural member repairs and replacements were based on the International Building Code – 2006 Edition, and ASCE 07-05.
