INVESTIGATION OF STRUCTURAL ADHESIVES

THIS PROJECT IS DESIGNED TO FURNISH FHWA WITH A NUMBER OF IMPORTANT PRODUCTS IN PREPARATION FOR ACCELERATED LIFE TESTING (ALT) OF A LARGE SCALE MODEL JOINT AND A LONG TERM FULL SCALE BEAM TEST TO VERIFY THE ALT. THE MOST IMPORTANT PRODUCT IS A PROCEDURE FOR INTRODUCING DESIRED MOISTURE LEVELS INTO LARGE AREA BONDS IN A RELATIVELY SHORT TIME. A SECOND PRODUCT IS THE ALT PLAN WHICH ACCOUNTS FOR THE BEHAVIOR OF INDIVIDUAL ADHESIVE MATERIALS. A THIRD PRODUCT IS A MODEL JOINT DESIGN. FINALLY, THREE ADHESIVES WILL BE CHARACTERIZED TO OBTAIN THE BEHAVIORAL PARAMENTERS NEEDED TOSET ALT EXPOSURE LIMITS. ONE OF THE ADHESIVES IS A TRI FORMULATION FOR WHICH FHWA WILL ACQUIRE LIMITED RIGHTS. IF THE PROJECT IS SUCCESSFUL THROUGH PHASE II, THE AUTHORS ANTICIPATE THAT THERE WILL BE INTEREST IN DEMONSTRATION PROJECTS FOR BOTH NEW CONSTRUCTION AND REPAIR APPLICATIONS FOR BONDED STRUCTURES. INITIALLY, THE BONDED STURCTURES MAYNOT BE PRIMARY LOAD BEARING MEMBERS, UNLESS ADHESIVES ARE USED TO AUGMENT BOLTS FOR SPECIAL APPLICATIONS. NEW ADHESIVES WHICH HAVE GREATER ENVIRONMENTAL RESISTANCE WOULD REDUCE THE NUMBER OF BOLTS.