Title: 
            A Half-Century of Involvement with Joints and Bearings and Some Lessons Learned
        
        
            Author(s): 
            Stewart C. Watson
        
        
            
                Publication: 
                Symposium Paper
            
            
                Volume: 
                164
            
            
                Issue: 
                
            
            
                Appears on pages(s): 
                1-44
            
            
                Keywords: 
                bridge bearings; bridges (structures); joints (junctions); pavements; sealing; General
            
            
                DOI: 
                10.14359/1588
            
        
        
            Date: 
            11/1/1996
        
        
            Abstract:
            From shortly before the entry of the U. S. in World War II and to the present, the author has been continuously involved in the design, testing, manufacturing, and observation of the performance of joints of all types, from pavements to bridges, and bearings of all types, from the old rockers to elastomeric, pot, disc, and then to earthquake isolation concepts. Starting out with load transfer devices buried in concrete pavement joints for state highways and airfield pavements to field molded sealants and then compression seals, the design trend in pavements has been from longer 100 ft panels (30 m) to relatively short panels of 15 ft (4.5 m). This has greatly simplified the sealing problem, since the distance changes between joint interfaces of shorter length panels obviously are much less in creep-shrink and thermal volume change.     With respect to bridges, the design trend has been reversed, going from relatively short decks of 40 ft (12 m) to longer and longer spans, greatly complicating the sealing problem. It was in this confused design period that the writer worked toward developing sealing and bearing systems for every conceivable type pavement or bridge structure. Some lessons learned during the past 50 or more years are the subject of this paper.