GM Pontiac Process Utility Holes Over Press Pit
May 07, 2021
20
| STATEMENT OF PROBLEM Once the press pit steel design was complete, CCC provided the pit framing steel model / 2D drawings to GM to provide to Rotem for their use. Rotem placed approximately 45 openings through the rebar SOD, and provided the 2D process drawing to GM/CCC. This drawing underwent 10 revisions by Rotem. When CCC placed the final (Rev10) 2D drawing of the holes over the framing, it was found that many were hitting the edges of beam flanges and had to be moved by CCC / ok''''d by GM & Rotem. In this instance CCC had to rework process design to work with the facility design, when in fact Rotem should have revised their drawings. Rotem drawing revisions were still being issued at the time that the SOD was preparing for pour, which changed the way the holes were done. Originally the small holes were to be cored and large holes CIP with pipe. Because GM did not know if Rotem would release additional changes, GF/CCC proceeded with coring all of the holes instead of CIP. COURSE OF ACTION CCC and IBI relocated utility holes which clashed with steel and provided final to GM to get back to Rotem. CCC cored all of the holes since it was unknown at the time of slab pour if any of the hole locations would change. LESSON LEARNED 1) If the process designer cannot provide full design before facility, then they need to work their design around the facility design. Once the facility IFC drawing is released, any further re-design that needs to take place due to process design changes should be at added cost. 2) Revisions to process drawings must have a cutoff date. CCC had to scramble to constantly check process drawing revisions against construction drawings, and revisions were ocurring while slab rebar and embeds were being installed by CCC. |
