On May 26-27, Oregon State University (Corvallis, OR) hosted the 2017 National Student Steel Bridge Competition.
Taking a brief break: University of Missouri-Kansas City
This yearly challenge gives students an opportunity to work as part of a real-world design team directly applying engineering principles, and to test their skills in structural design, fabrication, scheduling, and project management. Students really savor the chance to prove their school’s engineering excellence, and this applied learning project gives ample opportunity for their competitive spirit!
Teamwork and project management are essential in this intercollegiate competition, to produce a scale model bridge that satisfies stringent requirements in the categories of stiffness, lightness, construction speed, display, efficiency, and economy.
The Bentley Institute is pleased to continue as a national sponsor for the ninth year, providing not only financial support but also free STAAD.Pro software and learning materials to all participating teams (see the 2017 NSSBC sponsorship blog).
The rules of the Student Steel Bridge Competition change annually, simulating a request for proposal and resulting in a 1:10 scale model of a steel bridge that demonstrates each participating ASCE student chapter’s design and construction plan. The rules are flexible enough to accommodate a range of designs, and to encourage innovation.
This year 227 teams from the United States, Canada, Mexico, China, and India competed in the 2017 Student Steel Bridge Competitions, held during regional ASCE Student Conferences.
43 teams earned an invitation to the national finals, as the 2017 NSSBC Qualifying Teams.
The 2017 NSSBC began on Friday, May 26 with team registration, bridge set up, and display judging. The teams are available to explain their design to others, and answer questions. However, they spend just as much time scrutinizing the details of their competitors’ bridges! Students frequently inspect (and photograph) the details (especially connections) of other teams’ bridges.
On Saturday, May 27 the main competition began, with timed construction followed by lateral and vertical load testing and a final weigh station. First, the designated builders from each team carefully placed each individual tool and component in the staging area. Strategy is essential, to achieve the complimentary goals of having both the fastest build time and the lowest building cost; while more team members increase construction speed, they also result in higher construction costs.
While judges looked on, to ensure the many rules are observed, each team’s builders raced the clock to construct their bridge—while attempting to avoid any penalties. One piece at a time, students ran components of their bridge over to the builders, who scrambled to construct their bridge as quickly as possible. Methods were particularly varied this year!
This year Lafayette College (from Easton, PA) won the construction speed category, with a time of 3.55 minutes (University of Wisconsin, Platteville won in 2016 with a time of 2.62 minutes, but the fastest time in 2015 was 4.00 minutes)!
After the judges evaluated the construction of each bridge, deemed it sound, and recorded the official time (adding any penalties), each team moved their bridge to the first load testing station. There, the students applied a standardized lateral load test. Decking was placed at the center of the span and 75 pounds were added to the decking; a 50 lb. lateral pull was applied at deck level, and the sway must not exceed 1 inch.
Presuming the lateral load test was passed, each bridge then proceeded to the vertical load test. Two sections of decking were added at specified locations (unknown until that day), and three vertical deflection targets were set.
Cal State Northridge and U Texas San Antonio load their bridges
25-pound lengths of steel angle were placed on the bridge--one at a time—with 50 pounds preload added to each decking unit, gradually adding weight to achieve a total load of 2,500 pounds. Sway cannot exceed 1 inch, and deflection cannot be more than 3 inches downward on any target.
These tests are designed to be rigorous, because the rules simulate the same requirements that dictate the design and construction of full-scale bridges, including standards for strength, durability, constructability, usability, functionality, and safety.
The final stop for each bridge was the weigh station. This year’s lightest bridge was California Polytechnic State University, San Luis Obispo, at just 97 pounds. In fact, the top 5 bridges in the lightness category were lighter than last year’s lightest (University of Florida won the category in 2016, at 113 pounds).
Each bridge was ultimately judged on the following categories: display, construction speed, lightness (lowest total weight), stiffness (lowest aggregate deflection), construction economy (lowest construction cost), and structural efficiency.
If you missed our posts about the 2017 NSSBC on Facebook, live from the competition….
The winners of the 2017 ASCE/AISC National Student Steel Bridge Competition are:
1st place: École de Technologie Supérieure
2nd place: Lafayette College
3rd place: California Polytechnic State University, San Luis Obispo
All of the participating teams are to be congratulated for their dedication, hard work, and for jobs well done!
You can read more about the competition at http://www.aisc.org/steelbridge, and view details of the full 2017 results at http://www.nssbc.info/History/2017NSSBCRankings.pdf