The bridges across our nation face serious trouble. Funding for our DOT’s has been labeled as a primary reason for the decline of the nation’s infrastructure. Unfortunately the I-35W tragedy in Minnesota in 2007 has brought attention to the deterioration of the nation’s bridges. The most recent issue of “Better Roads” magazine reports that 10.9% of all bridges are Structurally Deficient. Nationally this means over 61,000 bridges have structural problems. The odds of us driving over these bridges everyday is a certainty. Below are the 2007 results for local area bridges from the Better Bridges 2007 Bridge Inventory Issue.
|State||Total Bridges||Structurally Deficient (SD)||SD%|
The current methods of Bridge Inspection are outdated and inaccurate at best. A typical non-destructive inspection is to remove all asphalt overlay. A chain drag or hammer blow test are performed to sound for voids within the bridge deck and a visual inspection is made to look for cracks and other indications of problems. A destructive test is to core drill samples of the bridge deck to inspect conditions.
- Continue to perform traditional methods of inspecting bridges.
- Perform a bridge deck deterioration map using GPR technology.
- As shown above, traditional methods of inspection are subjective and unreliable and allow for large amounts of human error during inspection. In addition these inspections offer zero quantitative data for comparisons from one year to the next.
- Construction Solutions offers Ground Penetrating Radar technology to assess with quantitative data the condition of the bridge deck. This technology can be used without the costly removal of the asphalt overlay. Quantitative data results can be compared from one year to the next. In addition construction companies that have been contracted to repair bridges can also use GPR to identify specific areas in need of repair. This allows companies to repair specific problem areas. Having specific data showing deterioration severity allows DOT agencies to maximize the repairs for the specific funding allowed.