Date of Award

Fall 2008

Document Type


Degree Name

Doctor of Philosophy (PhD)


Materials and Infrastructure Systems

First Advisor

Erez N. Allouche


Third-party damage to the buried infrastructure like natural gas pipelines, water distribution pipelines and fiber optic cables are estimated at $10 billion annually across the US. Also, the needed investment in upgrading our water and wastewater infrastructure over the next 20 years is estimated by Environmental Protection Agency (EPA) at $400 billion, however, non-destructive condition assessment technologies capable of providing quantifiable data regarding the structural integrity of our buried assets in a cost-effective manner are lacking. Both of these areas were recently identified several U.S. federal agencies as 'critical national need'. In this research ultra wideband (UWB) time-domain radar technology was adopted in the development of sensory systems for the imaging of buried utilities, with focus on two key applications. The first was the development of a sensory system for damage avoidance of buried pipes and conduits during excavations. A sensory system which can be accommodated within common excavator buckets was designed, fabricated and subjected to laboratory and full-scale testing. The sensor is located at the cutting edge (teeth), detecting the presence of buried utilities ahead of the cutting teeth. That information can be used to alert the operator in real-time, thus avoiding damage to the buried utility. The second application focused on a sensory system that is capable of detecting structural defects within the wall of buried structures as well as voids in the soil-envelope encasing the structure. This ultra wideband sensory system is designed to be mounted on the robotic transporter that travels within the pipeline while collecting data around the entire circumference. The proposed approach was validated via 3-D numerical simulation as well as full-scale experimental testing.