Columbia subject headings:
Dams--Testing--Congresses.
Foundations--Testing--Congresses.
Nondestructive testing--Congresses.
Harvard subject headings:
Princeton subject headings:
Bridges--Foundations and Piers--Testing--Congresses.
Dams--Foundations--Testing--Congresses.
Ground penetrating radar--Congresses.
Nondestructive testing--Congresses.
Seismic refraction method--Congresses.