PRINCIPLES FOR A PROGRAMME OF TESTS TO STUDY THE NATURAL STRESSES AND DEFORMATIONS IN THE BITUMINOUS DECK SURFACING/ DECK PANEL (ORTHOTROPIC PLATE) COMPOSITE SYSTEM RESULTING FROM THE EFFECTS OF TEMPERATURE

GRUNDLAGEN FUER EIN VERSUCHSPROGRAMM ZUR UNTERSUCHUNG DER EIGENSPANNUNGEN UND VERFORMUNGEN IM VERBUNDSYSTEM BIT. BRUECKENBELAG - FAHRBAHNBLECH (ORTHOTROPE PLATTE) INFOLGE VON TEMPERATUREINFLUESSEN

IT APPEARS TO BE NECESSARY, APART FROM STUDYING THE STRESS ON BRIDGE SURFACINGS AND THE DECK PANEL CAUSED BY TRAFFIC LOADING, TO EXAMINE THE BEHAVIOUR OF THE BONDED SYSTEM IN VARIOUS TEMPERATURES TOGETHER WITH THE EFFECTS OF THE NATURAL STRESSES WHICH OCCUR. LABORATORY TESTS ARE BEING CARRIED OUT ON AS LARGE SAMPLES AS POSSIBLE, FOR EXAMPLE SECTIONS OF ORTHOTROPIC SLABS SEVERAL SQUARE METRES IN AREA. THESE SAMPLES HAVE A STANDARDIZED STRUCTURE, I.E. STRUCTURE AND COMPOSITION CORRESPOND TO SYSTEMS MAINLY USED IN PRACTICE TODAY. THE SAMPLES ARE BEING EXPOSED UNDER CONTROLLED CONDITIONS TO DEFINED TEMPERATURES OVER A FAIRLY LONG PERIOD OF TIME (IN SOME CASES SEVERAL DAYS); DURING THIS TIME MEASUREMENTS ARE BEING MADE OF THE DEFORMATION WHICH OCCURS AT VARIOUS POINTS ON THE STEEL AND ON THE SURFACING. AS WELL AS THIS, ON SAMPLES OF THE SURFACING MATERIALS TO BE EXAMINED UNDER THE SAME TEMPERATURE CONDITIONS BY MEANS OF STATIC LOADING TESTS, THE MODULUS OF ELASTICITY OF THE SURFACING MATERIAL CORRESPONDING TO EACH TEMPERATURE CONDITION COULD BE DETERMINED SO THAT, BY MEANS OF THE DEFORMATIONS MEASURED ON THE SLAB SAMPLES, THE STRESSES WHICH OCCUR THERE AND THEREFORE THE STRESSES IN THE SURFACING COULD BE DETERMINED. PARALLEL TO THIS WORK, MEASUREMENTS ON STRUCTURES ARE ALSO TO BE CARRIED OUT.