Elastomeric expansion seal

Abstract

An expansion joint seal for use in roadways, bridges and the like adapted for use with a pair of elongated, parallel spaced-apart edge members defining a gap therebetween and each of the edge members having a generally C-shaped cavity opening towards said gap. The seal includes mounting beads on each of its longitudinal edges for reception within the aforesaid edge member cavities and a double walled, resilient web construction spanning the aforesaid gap and being attached to the mounting beads. The double walls of the web are disposed in an upper and lower relative relationship to one another and are connected to the mounting beads at correspondingly upper and lower portions thereon. The upper and lower web walls fold downwardly upon movement of the edge members towards one another and corresponding reduction in width of the gap. The upper and lower walls are connected to one another by a pair of downwardly extending struts which cause the upper and lower walls to fold in a desired manner while also providing additional strength to the configuration. The upper wall is surmounted by an inverted, V-shaped crown which folds upwardly away from the downwardly folding upper wall upon compression of the seal. The upwardly folding crown portion thereby functions to eject incompressibles out of the gap and/or to preclude the disposition of incompressibles in the gap.

I claim: 
     
       1. An expansion joint seal for bridging and sealing a gap between a pair of spaced-apart elongated edge members being respectively disposed in a pair of structural slabs to define the gap therebetween, each said edge member having in cross-section a generally C-shaped cavity with a preselected radius of curvature, each said cavity opening towards said gap defined between said edge members wherein each said cavity opening is defined between opposed projecting portions of said respective edge members spaced from each other at a distance less than the maximum dimension within said cavity taken generally parallel to said opening, said seal comprising: a web portion spanning said gap and a mounting bead portion extending along each longitudinal edge of said web portion wherein each of said mounting bead portions is received within said cavity of a corresponding edge member, and each said mounting bead having in cross-section an outer surface portion for matching engagement with said cavity with opposed portions of said mounting bead correspondingly abutting said opposed projecting portions of said edge member whereby relative lateral movement of said mounting bead with respect to said edge member is resisted and, said web portion including upper and lower walls spaced apart from one another to span said gap and being attached along their longitudinal edges to correspondingly upper and lower portions of said mounting bead portions wherein each of said walls includes a longitudinal, downwardly extending fold located substantially along the center line of said gap, said web portion further including a pair of strut members extending between said walls in a downwardly converging relationship with respect to one another for coordinating the movement of said walls during expansion and contraction of said seal, and the upper surface of said upper wall having an inverted V-shaped crown portion joined thereto and located substantially along the center line of said gap whereby the apex of said crown portion is adapted to remain disposed below the upper surface of the structural slabs associated therewith throughout the operational range of said seal.   
     
     
       2. The expansion joint seal is set forth in claim 1 wherein each of said mounting beads is in cross-section of hollow, tubular configuration and includes a spring shaped wall portion extending between said opposed portions of said mounting bead which abut said opposed projecting portions of said edge member. 
     
     
       3. The expansion joint seal as set forth in claim 2 wherein each spring shaped wall portion is of generally S-shaped configuration. 
     
     
       4. The expansion joint seal as set forth in claim 1 wherein said struts are joined to and extend between said walls at corresponding points generally adjacent to the edges of said downwardly extending folds. 
     
     
       5. The expansion joint seal as set forth in claim 4 wherein the edges of said crown portion join said upper wall at points generally coincident with the corresponding points at which said struts join said upper wall. 
     
     
       6. The expansion joint seal is set forth in claim 2 wherein said struts are joined to and extend between said walls at corresponding points generally adjacent to the edges of said downwardly extending folds. 
     
     
       7. The expansion joint seal as set forth in claim 6 wherein the edges of said crown portion join said upper wall at points generally coincident with the corresponding points at which said struts join said upper wall. .Iadd. 8. An expansion joint seal for bridging and sealing a gap between a pair of spaced, elongated joint edge members respectively disposed in a pair of structural slabs to define the gap therebetween, each edge member having a seal-retaining cavity opening toward the gap defined between the edge members, said seal comprising: a web portion spanning the gap and a mounting bead portion extending along each longitudinal edge of said web portion wherein each of said mounting bead portions is received within the cavity of the corresponding edge member, each said mounting bead portion having in cross section an outer surface portion for engagement with said cavity whereby relative lateral movement of said mounting bead portion with respect to the edge member is resisted, said web portion including an upper wall and a lower wall spaced from one another to span the gap and being connected along their longitudinal edges to corresponding upper and lower portions of said mounting bead portions, wherein at least one of said walls includes a longitudinal, downwardly extending fold located substantially along its mid-portion, said web portion further including a pair of strut members extending between said walls in a downwardly converging relationship with respect to one another for coordinating the movement of said walls during expansion and contraction of said seal, the upper surface of said upper wall having a crown portion located substantially along the mid-portion of said upper wall, whereby the top surface of said crown portion is adapted to remain disposed below the upper surface of the structural slabs associated therewith throughout the operational range of said seal. .Iaddend..Iadd. 9. The seal of claim 8 wherein said upper crown portion has an outer surface of generally convex shape. .Iaddend..Iadd. 10. The seal of claim 8 wherein said upper crown portion is defined by upper crown leg portions, each of which has an inner and an outer end, said inner ends being joined together at an obtuse angle to form an inverted, substantially V-shape with the apex of the V directed upwardly. .Iaddend..Iadd. 11. The seal of claim 8 wherein the edges of said crown portion join said upper wall at points generally coincident with the corresponding points at which said struts join said upper wall. .Iaddend..Iadd. 12. The seal of claim 11 wherein said lower wall fold is defined by lower leg portions, each of which has an inner and an outer end, said inner ends being joined together to form a substantially V-shape with the apex of the V directed downwardly. .Iaddend..Iadd. 13. The seal of claim 12 wherein said lower leg portions are so disposed as to define an cute angle therebetween. .Iaddend..Iadd. 14. The seal of claim 12 wherein said lower leg portions are so disposed as to define an obtuse angle therebetween. .Iaddend..Iadd. 15. The seal of claim 12 wherein said upper and said lower walls of said intermediate web portions are substantially parallel. .Iaddend.