Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7559720 | Culvert bundle for stream crossings and flow-through bridge abutments | Calvin D. VanBuskirk | 2009-07-14 |
| 7080956 | Open bottom box culvert | Calvin D. VanBuskirk | 2006-07-25 |
| 6874974 | Reinforced soil arch | Calvin D. VanBuskirk | 2005-04-05 |