METHOD OF VIBROACOUSTIC TRUSS TESTING Russian patent published in 2019 - IPC G01M7/00 

FIELD: test technology.

SUBSTANCE: invention relates to non-destructive dynamic testing of building structures, in particular to the testing of truss members. Method consists in the excitation in the rod of forced elastic oscillations with varying frequency and registering the frequency of its resonant oscillations. One of the rods of the upper belt of the tested truss is selected as an excitable one, the nodes at the ends of this rod are connected with a rigid coupler of adjustable length, and resonant frequency thereof is re-registered. In the case of a sharp increase in the resonant frequency, the rod is recognized as defective. Then, by transferring and adjusting the length of the tie, the ends of each of the rods of the lower chord and the grid are alternately connected. For each compound, the nature of the change in the resonant frequency of the same excited rod of the upper belt is re-controlled, and in case of a noticeable increase, the corresponding constricted, hard-to-reach rod of the lower belt or lattice is rejected. Then other easily accessible rods of the upper belt and, if necessary, gratings, and for each of them, are selected as excited ones in series, and their bordering difficult-to-reach rods of the lower belt and grating are re-tested.

EFFECT: increased efficiency and reduced complexity of the test.

1 cl, 1 dwg