NDE Conference on Civil Engineering: The 7th Structural Materials Technology (SMT ): NDE/NDT for Highways and Bridges and the 6th International Symposium on NDT in Civil Engineering (NDT-CE) Conference on Civil Engineering Conference on Civil Engineering, Aug 2006, Sheraton St Louis, MO, United States. pp.357 Conference on Civil Engineering, Aug 2006, Sheraton St Louis, MO, United States. pp.357-, 2006