Sponsors:

Norfab Steel and Fabrication

Jenco Inc.

Neuco Inc.

Mayorga's Welding

Final Design

The steel bridge design will be competing in the 2013 ASCE PSWC (Pacific Southwest Conference) Student Steel Bridge Competition. This competition gathers students from different universities and challenges them to create a model steel bridge with different constraints. Students are responsible for analyzing serviceability (vertical and lateral loading) of the bridge, testing material properties, fabricating the bridge, improving construction time and cost analysis of the bridge. This competition helps student gain a better understanding of the design process and real world application. The competition will be held at the University of Southern California (USC) on April 4-6, 2013.

Purpose

The River City Development Corporation (RCDC) is asking for a bridge design that will provide direct access across the river to the suburbs.  Accelerated Bridge Construction (ABC) specifies the bridge has to provide clearance for tour boats and should cantilever over a historic billiard parlor.  RCDC specifies a steel bridge design for speed of construction, high strength to weight ratio and high level of recyclable content.  Due to site restrictions on the location, staging area, and the dimensions and weight of equipment, transportation will be limited by small and narrow streets of River City. RCDC has requested a demonstration of the designed bridge by using a 1:10 scaled model. Models will be tested on stability, strength, and serviceability based on vertical and lateral deflections.  Additionally, the bridge will be rated based on durability, constructability, usability, stiffness, construction speed, efficiency, economy and aesthetics by a group of third party engineers.

History

Northern Arizona University has competed in the AISC/ASCE Steel Bridge Competition for the past several years.  The current steel bridge team will analyze the bridges of years past to maximize success in 2013. The 2007 Bridge Team had problems with construction time.  The amount of connections required for that design was high and led to an increased construction time cost.  The 2008 Bridge Team had problems with torsion.  This led to high deflections in the members.

In 2012, NAU’s Steel Bridge Team placed 9th overall.  One of the major issues faced by the 2012 bridge was the donated steel used for fabrication went untested.  The team members assumed the grade of steel instead of testing the steels themselves. This led to excessive deflections in the members.  This year, the bridge team plans to test the steel, minimize connections, and develop adequate footings for the bridge to prevent the same issues from occurring during the 2013 competition.