Abstract: An ice hockey arena having an ice rink surrounded by tiers of spectator seats, wherein said ice rink has a playing surface above a first concrete base having a first width and a first length, a first series of cooling pipes within said first base and an insulation layer between said first base and the ground, the improvement comprising a second concrete base having a second width and a second length above said first base wherein said second width is greater than said first width; and a second series of cooling pipes within said second base. The method allows for the enlargement of a standard NHL ice playing surface to International Ice Hockey Federation width playing surface in a cost-effective manner while maintaining acceptable spectator sight lines.

Abstract: A structure is provided having two opposing nested pairs of outwardly convex roof arches mounted for rotation about a generally horizontal axis. Each pair of nested roof arches can be rotated about its axis from a lowered nested condition to a raised condition where the inner portion of one arch partially overlaps the other arch of the nested pair. In a preferred arrangement the arches extend between supports on diametrically opposing sides of a stadium building, which has an upper opening. The arches in their raised condition cover the stadium opening and in their lowered condition maintain the stadium substantially open to the elements. The turning moment exerted by the arches is sustained through struts by floats within liquid contained in caissons forming a foundation of the structure. The floats are shaped and guided to follow a path within the liquid as the associated arch rotates such as to substantially balance the turning moment of the latter as they move.

Abstract: A structure is provided having two opposing nested pairs of outwardly convex roof arches mounted for rotation about a generally horizontal axis. Each pair of nested roof arches can be rotated about its axis from a lowered nested condition to a raised condition where the inner portion of one arch partially overlaps the other arch of the nested pair. In a preferred arrangemnt the arches extend between supports on diametrically opposing sides of a stadium building, which has an upper opening. The arches in their raised condition cover the stadium opening and in their lowered condition maintain the stadium substantially open to the elements. The turning moment exerted by the arches is sustained through struts by floats within liquid contained in caissons forming a foundation of the structure. The floats are shaped and guided to follow a path within the liquid as the associated arch rotates such as to substantially balance the turning moment of the latter as they move.