The 10 years survey of the Szent István Tisza-bridge at Szolnok (built in 1992) has found an extra deflection of ~7 cm at midspan. In order to investigate the above feature Pont-TERV Engineering Consultants has been charged with a control statical analysis. The multispan continuous beam superstructure consists of a three span right side flood bridge, a three span river bridge and a nine span left side flood bridge. The flood bridges have been constructed by the incremental launching technology, the river bridge by the free cantilever method. The spans are 28,8 + 2x36 + 69 + 120 + 69 + 8x36 + 28,8 m long.

The analysis has been made with the RM2000 program of TDV Austria, invented for the analysis of prestressed concrete bridges. The program is based on a spaceframe FEM program, but contains special modules for the analysis of the cross-sections, the tendon geometry, the prestressing actions and losses and for the time dependent modelling of the creep and shrinkage behaviour.

The number and geometry of the tendons, the prestressing data and the loads has been taken into consideration according to their final (as built) values. The creep and shrinkage process during the construction stages could be handled according to the real consrtuction dates as well. Beyond the calculation of the deflections according to several initial condition, the stresses belonging to the developed strains and the additional later deflections has been also checked.