Richard Giessel is the state quality assurance engineer at Alaska DOT & Public Facilities.
What’s your background and area of expertise?
I have been a professional civil engineer in Alaska since 1981, but my interest in science and engineering began 15-20 years earlier with a subscription to Popular Mechanics and participation in science fairs. In high school, I was president of the Science Research Club. We ground a 12.5-inch diameter mirror for a refractor telescope that was so big we needed to design and build an observatory building to house it. I had completed mechanical and architectural drawing classes, so it was natural for me to design the structure and get the required approvals for construction. My role then evolved to construction superintendent and chief block layer. Completing the observatory building with my science club teammates was the highlight of my senior year in high school. My experience placing concrete footings and a slab, mixing mortar and laying block led to an interest in materials engineering that has never gone away, even though I have done significant work in hydraulics/hydrology and structural design over the last 40 years.
What’s your role with Alaska DOT?
As State Quality Assurance Engineer, my responsibilities are very broad yet with the common theme of improving quality and eliminating defects in the roads, bridges, ferry terminals, airfields and buildings designed, built and maintained under the authority of DOT & PF. I also am advocating for increased use of intelligent construction technologies through grants and shadow projects that provide continuous full coverage compaction mapping of soils, aggregates and asphalt mixtures.
What are some unique or noteworthy projects that used precast concrete?
My first major project after obtaining my civil engineering degree from the University of Michigan was hydraulic design of the wastewater collection and treatment facility for the Trail Lakes Fish Hatchery in Moose Pass, Alaska. This was Alaska’s first central salmon hatchery. It was designed to both enhance current salmon populations and restore natural salmon runs to other streams. A central hatchery collecting eggs and milt from multiple stream populations faces the danger of introducing viral pathogens into the entire population and any fishery downstream. In this case, the downstream fishery was the Kenai River, famous for its runs of king, red and silver salmon. A very interesting challenge was sterilizing up to 4,000 gallons per minute (gpm) of wastewater with the technology available in the 1979-80 time frame. How we solved that challenge is covered in a paper that I presented at a conference in 1981.
What benefits did precast concrete offer on that project?
For Trail Lakes Hatchery, we designed modules of precast concrete raceways to rear the fry. The modules allowed us to keep the populations isolated so an introduced virus from one egg take area would not wipe out the entire hatchery population. Precast raceways made installation of baffles and plumbing very efficient and consistent during construction. The precast raceway is still functioning well today after 40 years of production of approximately 35 million salmon fry per year.
How do you see the role of precast changing in the future?
Ultra-High-Performance Concrete (UHPC) will greatly improve the durability of many precast products in the future, especially elements with severe exposure like bridges in marine or freeze-thaw environments. UHPC has a compressive strength of 21-30 ksi and tensile strength of 3-5 ksi, so it could eliminate the need for shear reinforcing in many structural elements. The high strength, ductility and durability will allow significant reductions in the amount of concrete used, conserving raw materials. I’m very happy that my oldest son, Peter Giessel, P.E., S.E., is on ACI Committee 239, Ultra-High-Performance Concrete. It is rewarding to pass the torch to the next generation!