Joint structure at end of concrete floor slab of bridge

Abstract

A joint structure at an end of a concrete floor slab of a bridge according to an embodiment of the present invention is configured such that: a lowered step part is formed in an upper part of an expansion gap formed between ends of concrete floor slabs or an expansion gap formed between the end of the concrete floor slab and an abutment; joint layers, each made of an elastic asphalt mixture covered with a covering sheet, are formed in the lowered step part; and a paving material is placed on the joint layer to form a surface layer.

1 . A joint structure at an end of a concrete floor slab of a bridge, wherein
 a lowered step part is formed in an upper part of an expansion gap formed between ends of concrete floor slabs or an expansion gap formed between the end of the concrete floor slab and an abutment,   a single layer structure or a multilayer structure of a joint layer made of an elastic asphalt mixture covered with a covering sheet is formed in the lowered step part, and   a paving material is placed on the joint layer of the single layer structure or an uppermost joint layer of the multilayer structure to form a surface layer.   
     
     
         2 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 1 , wherein
 the asphalt mixture is such an asphalt mixture that a main material including butyl rubber or ethylene-propylene rubber and asphalt is heated and melted into a mixture, and the mixture is used as a binder.   
     
     
         3 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 1 , wherein
 an asphalt mixture which is the same as the asphalt mixture constituting the joint layer is used as the paving material constituting the surface layer.   
     
     
         4 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 1 , wherein
 a surface of the covering sheet serving as an outer surface of the joint layer is an adhesive surface.   
     
     
         5 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 4 , wherein
 the adhesive surface of the covering sheet is formed of such a mixture that a main material including butyl rubber or ethylene-propylene rubber and asphalt is heated and melted.   
     
     
         6 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 1 , wherein
 a covering surface of the covering sheet that covers the asphalt mixture is a rough surface.   
     
     
         7 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 6 , wherein
 the covering surface of the covering sheet is formed of a fiber sheet.   
     
     
         8 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 2 , wherein
 an asphalt mixture which is the same as the asphalt mixture constituting the joint layer is used as the paving material constituting the surface layer.   
     
     
         9 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 2 , wherein
 a surface of the covering sheet serving as an outer surface of the joint layer is an adhesive surface.   
     
     
         10 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 3 , wherein
 a surface of the covering sheet serving as an outer surface of the joint layer is an adhesive surface.   
     
     
         11 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 2 , wherein
 a covering surface of the covering sheet that covers the asphalt mixture is a rough surface.   
     
     
         12 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 3 , wherein
 a covering surface of the covering sheet that covers the asphalt mixture is a rough surface.   
     
     
         13 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 4 , wherein
 a covering surface of the covering sheet that covers the asphalt mixture is a rough surface.   
     
     
         14 . The joint structure at an end of a concrete floor slab of a bridge according to  claim 5 , wherein
 a covering surface of the covering sheet that covers the asphalt mixture is a rough surface.