Infrastructure protectionTechnology assesses bridge safety after powerful storms
Hurricanes and heavy rains often cause strong, overflowing river currents that can damage critical infrastructure, such as bridges. For example, after Hurricane Katrina, many National Guard convoys loaded with aid did not drive on bridges for fear the bridges could not support the heavy trucks. To safely transport, they had to use roundabout roads or boats to reach Katrina survivors. Loose or loosening soil is often the culprit in weakening bridge stability. Thus, an instrument that can quickly assess the soil conditions around bridge pillars is a top priority.
Hurricanes and heavy rains often cause strong, overflowing river currents that can damage critical infrastructure, such as bridges. For example, after Hurricane Katrina, many National Guard convoys loaded with aid did not drive on bridges for fear the bridges could not support the heavy trucks. To safely transport, they had to use roundabout roads or boats to reach Katrina survivors.
Loose or loosening soil is often the culprit in weakening bridge stability. Thus, an instrument that can quickly assess the soil conditions around bridge pillars became a top priority for the Department of Homeland Security (DHS) Science and Technology Directorate (S&T), as well as state and local governments.
The result of the project, conducted by DHS S&T’s Coastal Hazards Center of Excellence, is the lightweight but efficient In-situ Erosion Evaluation Probe, also known as Soil Probe. The project has delivered the probe as well as an accompanying standard (coming out this fall) that proves the viability of this technology.
S&T says that the tool, which only needs chargeable batteries to drive the water pump, is made up of a stiff cylinder and a pump that uses the water surrounding the bridge to jet away soil and sink the probe deeper. “After powerful storms come through, being able to quickly assess whether or not key transportation infrastructure can hold heavy trucks that deliver relief aid is vital,” said Eleanore Hajian, the DHS S&T Program Manager responsible for the Soil Probe project.
Departments of Transportation in many states could benefit from this instrument when there is a concern about bridge stability. Transportation and bridge engineers, contractors, even the Federal Emergency Management Agency (FEMA), could do field assessments as needs arise.
What the Soil Probe can do and how it works
The Soil Probe addresses the problem of scour, which is an engineering term describing the erosion of soil around a structure caused by water flow. Scour can make bridge pillars unstable. Usually after powerful storms, strong river currents wash away the soil around pillars and can even deposit new soil. New soil is less dense, so pillars can become unstable and fall when heavy equipment starts rumbling across a bridge.
