WORKING OUT OF CHARACTERISTIC VALUES FOR UNREINFORCED ELASTOMERIC BEARINGS USED IN PRECAST CONSTRUCTION

ERARBEITUNG VON MATERIALKENNWERTEN FUER UNBEWEHRTE ELASTOMER LAGER IM FERTIGTEILBAU

PREVIOUS WORK IN THIS AREA HAS CONCENTRATED ON BRIDGE BEARINGS MADE OF ELASTOMERIC PANELS HAVING STEEL PANELS VULCANIZED INTO THEM. THIS TYPE OF BEARING IS SELDOM USED IN PRECAST REINFORCED CONCRETE CONSTRUCTION BECAUSE OF ITS HIGH COST. AS IN THESE CASES HORIZONTAL DISPLACEMENTS ARE COMPARATIVELY SLIGHT AND THE TORSIONAL ANGLES ARE SMALL, ELASTOMERIC BEARINGS WITH LESS REINFORCEMENT, (SLABS OF CHLOROPRENE POLYMERIZATES) CAN BE USED. FIRST TESTS WITH BEARINGS OF THIS KIND CARRIED OUT AT THE INSTITUTE FOR CONSTRUCTION RESEARCH, TECHNICAL UNIVERSITY OF AACHEN, RESULTED IN THEIR USE IN THE CONSTRUCTION OF THE UNIVERSITY OF BOCHUM (BEARING PLATES BETWEEN PRECAST SUPPORTS). RESEARCH INTO THE PROPERTIES OF ELASTOMERIC MATERIALS FOR BEARINGS IN PRECAST CONSTRUCTION IS URGENTLY NECESSARY FOR THE FURTHER EVALUATION OF ELASTOMERIC BEARINGS, ESPECIALLY AS A BASIS FOR DETERMINING STRESS IN THE LOAD-DISTRIBUTING BEARING LAYER, AND OF THEIR BEHAVIOUR AT INTERFACES. ADEQUATE KNOWLEDGE OF THE DEFORMATION BEHAVIOUR OF UNREINFORCED ELASTOMERIC BEARINGS UNDER SHORT AND LONG TERM TREATMENT CAN CONTRIBUTE TO A SIGNIFICANT RATIONALIZATION OF PRECAST CONSTRUCTION.