PROCEDURE OF DIAGNOSTICS OF THE STATE OF ANCHOR BOLT BY THE METHOD OF FREQUENCY RESPONSE

The procedure of diagnostics of the state of anchor bolts has the primary objective estimation of the degree of adhesive damage of anchor bolts and concrete on the basis of identification of parametres of the depth of adhesive damage. The examination is realised on the place of assembly on the basis of appliction of non-destructive method of examination based on the appliction of experimental method of frequency response. The essence of that procedure consists of establishing corelation between the spectral qualities of the examined object (anchor bolt) and the parametres of the depth of the adhesive damage. Along with that, the greater depth of damage corresponds to the lower value of basic natural frequency of anchor bolt and the opposite, the lesser frequency of damage, the higher value of basic natural frequency of anchor bolt. Diagnostics of condition of anchor bolts according to the suggested procedure may be performed in two levels, relative, by comparation of spectral characteristics of more anchor bolts of similar characteristics, for example in the assembly of one machine/plant, or in absolute identification of the degree of adhesive damage of each individual anchor bolt by the parametres of the depth of dhesive damage. For the dignostics of condition at the relative level it is enough to have at one's disposal the results of examination of spectral qualities of anchor bolts by method of frequency response, while for the diagnostics of condition at the absolute level, i.e. the identification of the depth of adhesive damage of each individual anchor bolt, except for the knowledge of the experimentally determined spectral qualities, it is esential to know also basic parmetres of anchor bolts, for example: mass and number of nuts, radius of the longitudinal tree, nd radius of the kernel of anchor bolt, projected free length of anchor bolts, etc. Postupak dijagnostike stanja anker zavrtnjeva ima za primarni cilj procenu stepena adhezionog ostecenja anker zavrtnja i betona na bazi identifikacije parametra dubina adhezionog ostecenja. Ispitivanje se realizuje na mestu ugradnje, na bazi primene nedestruktivne metode ispitivanja koja se temelji na primeni eksperimentalne metode frekventnog odziva. Sustina postupka sastoji se u uspostavijanju korelacije izmedu spektralnih svojstava ispitivanog objekta (anker zavrtnja) i parametra dubina adhezionog ostecenja. Pri tome, vecoj dubini ostecenja odgovara niza vrednost osnovne prirodne ucestalosti anker zavrtnj