On May 25-26, University of Illinois at Urbana-Champaign hosted the 2018 National Student Steel Bridge Competition. Every year, more than 200 American Society of Civil Engineers (ASCE) student chapters form steel bridge teams, to prove their school’s engineering excellence and discover how their ability to apply engineering principles to a real-world design project stacks up against their competitors.

    

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 marked Bentley Institute’s 10th anniversary as a national sponsor, providing not only financial support but also free STAAD.Pro software and learning materials to all participating teams (see the 2018 NSSBC sponsorship blog ).

230 teams from the United States, Canada, China and Mexico competed in the 2018 Student Steel Bridge Competitions, held during regional ASCE Student Conferences. 43 qualified for, and 42 competed in, the national finals as 2018 NSSBC Qualifiers.

The teams design and test 1:10 scale model bridges that satisfy stringent requirements in the categories of stiffness, lightness, construction speed, display, efficiency, and economy.

The 2017 NSSBC began on Friday, May 25 with team registration, bridge set up, and display judging. The teams explain their designs, and scrutinize their competitors’ bridges, while mingling with representatives from the sponsors.

    

On Saturday, May 26 the main competition began, with timed construction followed by lateral and vertical load testing and a final weigh station. First, designated builders from each team place 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. 

   

Judges ensured the many rules were observed, as each team raced to construct their bridge as quickly as possible—while attempting to avoid any penalties. One piece at a time, students transfer components of their bridge  to the builders, who used various (and often creative) construction methods.

This year the winner for construction speed was École de Technologie Supérieure, at the lightning-fast speed of 1.85 minutes (followed closely by Lakehead Univeristy, at just 2.45) In 2017 Lafayette College (from Easton, PA) won the construction speed category, with a time of 3.55 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. The students applied a standardized lateral load test, with decking placed at the center of the span and 75 pounds 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.

   

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 rigorous tests are designed to simulate the 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 built by Illinois Institute of Technology, at just 112 pounds. In fact, 5 bridges were under 150 pounds, and another 30 were under 200 lbs.

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 live posts from 2018 NSSBC, please check them out on Facebook!

The winners of the 2018 ASCE/AISC National Student Steel Bridge Competition are:

1st place: Lafayette College

   

2nd place: California Polytechnic State University, San Luis Obispo

   

3rd place: École de Technologie Supérieure

   

You can view full 2018 results at http://www.nssbc.info 

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