METHOD FOR TESTING A PRESTRESSED CONCRETE CONDUIT

摘要

A method is provided for testing prestressed concrete pipe (12). In the method, elastic waves are serially induced at least three different inducing locations along the surface of the conduit. The shear wave (5) component of each induced elastic wave is detected by at least one, and preferably two, acoustic sensors (16) disposed at fixed sensing sites (17) along the conduit (12). The relationship between at least one parameter of each induced shear wave and the distance between each inducing location (15) and the acoustic sensor(s) (16), are correlated and compared with standard correlations to identify structural discontinuities in the conduit (12). In a typical example of the method, elastic waves are induced using a mechanical hammer (18) at multiple inducing sites (15) around a multiplicity of annuli along the length of the conduit. Each annulus is separated from adjoining annuli by 2-4 feet.