23   2020 Prize Bridge Awards
The winners of this year's Prize Bridge Awards span everything from a rugged section of Lake Tahoe's shoreline to a tight Idaho Canyon to a wide stretch of railroad tracks along Chicago's lakefront to a high-profile expressway in Philadelphia's Center City to the Hudson River's massive Tappan Zee.

  • Vine Street Expressway (I-676) Reconstruction Project—18th to 22nd Streets, Philadelphia
  • Anchor Bay Drive, St. Clair County, Mich.
  • Grand Avenue Bridge, Glenwood Springs, Colo.
  • Williams Creek (Shoup) Bridge, Salmon, Idaho
  • Manning Crevice Bridge, Riggins, Idaho
  • Pfeiffer Canyon Bridge, Big Sur, Calif.
  • Governor Mario M. Cuomo Bridge, Westchester/Rockland Counties, N.Y.
  • Broadway Bridge Over The Arkansas River, Little Rock/North Little Rock, Ark.
  • Portageville Bridge Replacement, Portageville, N.Y.
  • Sarah Mildred Long Bridge, Kittery, Maine/Portsmouth, N.H.
  • Bayou Sara Swing Bridge, Mobile County, Ala.
  • Frances Appleton Pedestrian Bridge, Boston
  • 41st Street Pedestrian Bridge, Chicago
  • East Shore Bridge, Lake Tahoe, Nev.
  • Andy Warhol (Seventh Street) Bridge, Pittsburgh
  • Winona Bridge, Winona, Minn.
  • BNSF Wind River Bridge, Skamania County, Wash.
  • I-240 MemFix4, Memphis, Tenn.
  • Liberty Bridge, Pittsburgh

60   Essential and Available
By Geoff Weisenberger
While the COVID-19 pandemic has taken a massive toll in terms of lives, jobs, and industries, the domestic structural steel industry remains vibrant.



16   How Low Can You Go?
By William A. Thornton, PE, PhD
A brief look at the lower bound theorem of limit analysis.

field notes
18   There and Back Again
Interview by Geoff Weisenberger
AISC's next board chair started off as an engineer--just not the type you’d think for the president of a prominent structural steel fabrication company.

business issues
20   Opportunity Knocks
By Bill Issler
Want to attract a new generation of shop labor? Try technology.