REHABILITATION AND MONITORED PRESTRESSING OF CORRODED TENDONS

The contribution deals with the issue of diagnostics and stressing of prestressing tendons on three bridges of the D1 motorway. In the years 2001-2004 there occurred a significant downturn of construction activity on the stated construction, culminating in 2002 in a complete cessation of construction. On the semi-built bridges constructed in span-by-span technology on support forms, all prestressing reinforcement crossing two to three fields were exposed to weather conditions – snow and rain. The investor commissioned the PROJSTAR PK s.r.o. firm for the elaboration of a diagnostics conception for the technical state of tendons, primarily from the standpoint of the degree of corrosion of the elements, a methodics for stressing and control of tendon tension, and finally a methodics for partial grouting or completely ungrouted tendons [1].