AMG, Inc. was commissioned to help a large soybean crush plant replace an in-ground hexane skim pit during a 14 day shutdown.
AMG decided to use a segmental precast concrete skim pit built in 4 segments, none of which exceeded 9’ in width or more than 100,000 lbs in weight to facilitate shipping. The precast segments were match cast by a B4 certified precast fabricator and shipped to the plant ready for assembly during the shutdown. After the segments were placed in the excavation and aligned, they were drawn together and locked tightly in place by 24 post tensioning strands fed through ducts cast into the segments. Finally, the skim pit was made water tight by pressure injecting urethane foam into the three construction joints between the four segments.
In order to complete the concrete skim pit in nine days, the solution required atypical construction techniques. Because the client was unfamiliar with these techniques, he requested a number of preliminary feasibility, constructability, and construction cost checks to confirm the viability of the approach to his satisfaction before giving approval to proceed.
The first step was to identify specialty subcontractors for each facet of the work.
Once these contractors were identified, a project budget cost was assembled from their provisional quotations based on preliminary sketches of the project. When the feasibility and cost of the project approach were demonstrated to the client’s satisfaction, final construction drawings were prepared.
The project execution came together with only couple of challenges.