Retractable roof for stadium structure

A roof assembly according to claim -0 wherein said dampening means comprise:

• a platform upon which said pivot mounts and said actuating means are mounted;
• lateral translating means attached to the base of said platform for supporting said platform and for allowing said platform to move laterally in a generally horizontal plane;
• and
• at least one platform damping means acting between the platform and a foundation of the structure for controlling horizontal movement of the platform,
• whereby the lateral movement of said platform may be controlled in response to earthquake loads.

A structure comprising:

• a first pair of nested outwardly convex arches comprising a first arch and a second arch spaced from said first arch said first and second arches mounted for rotation about a first generally horizontal axis;
• and
• a second pair of nested outwardly convex arches comprising a third and a fourth arch spaced from said third arch, said third and fourth arches mounted for rotation, about a second generally horizontal axis parallel to said first axis, between raised and lowered conditions and each having an arcuate cross-section in a vertical plane normal to said first and second axes, said first and second arches and said third and fourth arches in their respective lowered conditions being in a nested pair configuration and in their respective raised conditions being in a configuration with the inner potion of said first arch partially overlapping the outer portion of said second arch and the inner portion of said third arch partially overlapping the outer portion of said fourth arch, said arches extending between opposing sides of an area said first and second arches and said third and fourth arches being rotatable in opposite directions between an open position in which each is in its respective lowered condition and a closed position in which each is in its respective raised condition, the inner edges of said second and fourth arches engaging in said closed position;
• a building structure within said area, said area being covered when said arches are rotated to said closed position and said area being uncovered when said arches are rotated to said open position;
• at least two struts having upper and lower ends, the upper ends pivotally connected to said first and third arches at a distance from said axis, the weight of said arches generating a variable turning moment about said axis dependent upon the stage of transition between the raised and lowered conditions;
• coordinating means coupled to said first and second arches and to said third and fourth arches for rotating said second arch as said first arch rotates and for rotating said fourth arch as said third arch rotates, said second and fourth arches rotating at a second angular velocity which differs from the first angular velocity of rotation of said first and third arches;
• a body of liquid adjacent the lower ends of each strut;
• float means, connected to the lower end of each strut, for applying a buoyant force to said arches through said strut opposite said turning moment when said float means is at least partially immersed in said body of liquid;
• guide means for constraining each said float means to follow a path within said liquid as said arches rotate, such that the total buoyant force, applied by said at least one strut to the arches, substantially counterbalances said variable turning moment throughout the transition of the arches between its raised and lowered conditions;
• and rotating means for rotating said arch panel between said raised and lowered conditions;
• and
• at least two double-acting double rod hydraulic cylinders mounted upon third supports and connected to said first and third arches at a distance from said axis.