Design News for Mechanical and Design Engineers

NEW! NTSB Reports: Construction Materials Contributed to I-35W Bridge Collapse
Minnesota's I-35W bridge collapsed under the weight of tons of sand and construction materials stored at two of the structure’s weakest points, according to reports released Monday by the NTSB. Full Story

UPDATE: Design Flaw Identified in Minnesota Bridge Collapse
A serious error in sizing parts of Minnesota's I-35W bridge may have lead to the deadly collapse last year. Full Story

Fatigue Could Loom Large in Bridge Collapses
Metal fatigue could be a cause in structural failures like the I-35W bridge collapse in Minnesota. The challenge lies in recognizing it. Full Story

Minneapolis Bridge Contract Awarded, Protest from Losing Bidders
The contract for the reconstruction of I-35W in Minneapolis was given to Flatiron-Manson, but two of the losing bidders are protesting the decision.  Full Story

Structurally Deficient Bridges on the National Highway System
View this map to get a look at how many structurally deficient bridges
exist on U.S. highways. View Now 

I-35W Bridge Collapse: Rush to Judgment
There seems to be a rush to judgment to find the flaws that caused the I-35W bridge to collapse in Minneapolis. The new theory—faulty steel gusset plates—strikes Contributing Editor Doug Smock as grasping at straws. Full Story

Focus of I-35W Bridge Collapse: Corroded Steel Bearings
Steel bearings designed to transfer huge longitudinal load shifts will get special focus as a triggering factor in the collapse of the I-35W bridge in Minneapolis Aug. 1. Full Story

UPDATE: Boston’s Longfellow Bridge Has Structural Deficiencies
The Longfellow Bridge in Boston, MA is slated for immediate repair during the state’s 40-day inspection of all bridges following the I-35W bridge collapse in Minnesota earlier this month. Full Story

Minnesota I-35W Bridge Collapse: A Reporter’s Perspective
Instinct took over for these three Minneapolis reporters when the I-35W bridge collapsed into the Mississippi River. Whether at home or still at work, they kicked into high gear and raced to the horrific scene. Full Story

Recovery Efforts Continue in Minneapolis’ I-35W Bridge Collapse
Vehicles and possibly victims could be under the fragments of deck found around the scene of the I-35W bridge collapse as recovery teams and contractors hurry to set up equipment for the removal of tons of concrete and twisted steel. Full Story

Readers Give Their Views on Why I-35W Bridge Collapsed
A few readers have responded to our coverage on the reasons why the I-35W bridge collapsed. What do you think brought the I-35W Bridge down? Post Comments

Recovery Efforts to Begin in I-35W Bridge Collapse
The NTSB has given the go ahead to begin recovery efforts following last Wednesday’s collapse of the I35W bridge in Minneapolis, MN. Cranes, being brought in to remove the portions of the highway collapse, are being put in place as early as today. Full Story

NTSB Use Accident Scene Mapping Team to Determine I-35W Minneapolis Bridge Failure
As the NTSB investigates Minneapolis' I-35W bridge collapse, its "Go Team" will use software to survey the scene and determine the cause of the structure failure. Full Story

University of Minnesota’s I-35 Bridge Fatigue Evaluation: A Closer Look
The collapse of Minneapolis’ I-35W bridge into the Mississippi River has given new visibility to a deck truss fatigue report on the bridge, performed by the University of Minnesota’s Center for Transportation Studies in 2001. Full Story

Structurally Deficient Bridges in the United States
Though the conditions that triggered the catastrophic collapse of I-35W are not yet known, speculation surrounding the rest of the country’s bridges has begun. A look at current bridge ratings gives insight into what “structurally deficient” means, as well as some methods for prevention. Full Story

Minneapolis I-35W Bridge Collapse: A Truss Failure?
The collapse of the I-35W bridge in Minneapolis, MN is the ultimate engineering calamity. DN Calamities expert Myron J. Boyajian shares his analysis of what likely caused the bridge failure. Full Story

I-35 Bridge Collapse: Was Structure or Metal Fatigue to Blame?
Since the devastating collapse of Minneapolis' I-35W bridge into the Mississippi River on August 1, inspectors are scrambling to find concrete reasons for the bridge's failure. When the dust settles, will the bridge structure itself be to blame, or was metal fatigue the true cause of the collapse? Full Story

A Bridge Builder’s View of the I-35W Disaster
Jack Parker, president of 79-year-old bridge builder Reed & Reed, cautions against speculation behind the cause of Minneapolis' I-35W bridge collapse. Full Story

UPDATE: Boston’s Tobin Bridge is Falling to Pieces
A 57-year-old span of bridge in Boston is giving boaters a reason to panic. Over the past two weeks, debris falling from the Tobin Bridge has broken windshields and caused other damages to the boats and vehicles below at the Chelsea Yacht Club. Full Story

Boston's Tobin Bridge: Battered, bent and shaky
Boston's huge Maurice J. Tobin cantilevered truss bridge backs up daily with the city's famously awful bumper-to-bumper traffic. With the horrific Minneapolis I-35 bridge collapse last night, it makes one trapped in traffic on "The Tobin" all the more nervous. Full Story