| 摘要 |
A structure, which after construction is mobile and dynamic and connects two points separated by a natural or manmade obstacle, allows permanent crossing of this obstacle. The structure comprises a deformable deck (1) extending between said two points, a set of elements (2, 3), of elongate shape, having three openings (5A, 5Α', 5B), a first opening (5A, 5A') at each end of the elements (2, 3) and an intermediate second opening (5B) positioned between the first two openings (5A, 5A') present at the ends of the elements (2, 3), said openings (5, 5A, 5Α') accepting ball joints used to form hinges (4), each element (2, 3) being made up of a short first part between a first opening (5A) and the intermediate opening (5B) and of a longer second part between the other first opening (5A') and the intermediate opening (5B), the elements (2, 3) being arranged in pairs, with rotational mobility, about a central hinge (4) consisting of a ball in the intermediate openings (5B) of two elements (2, 3). An assembly of a number of pairs of elements (2, 3), which assembly is achieved using balls inserted into the openings (5A, 5A') arranged at the ends of each element (2, 3), is arranged along the deck (1), on one side or on both sides of the deck (1) in a plane substantially perpendicular to the axis of said hinges (4) and allowing relative movement of the elements (2, 3) from a first position towards a second position which movement takes place in said plane perpendicular to the axis of the hinges (4). Drive means (8) are positioned at one or both ends of said structure in order to adjust the length of the deck (1). The structure comprises drive means (8) arranged in such a way that when the means (8) come into action, they drive the assembly of pairs of elements (2, 3), said short parts of the elements (2, 3) being positioned on the upper part of the pairs of elements (2, 3) which are arranged at the ends of the structure while said short parts of the elements (2, 3) are arranged on the lower part of the pairs of elements (2, 3) which are arranged towards the centre of the structure so as to cause the central part of the deck (1) to adopt a dome shape when the means (8) are actuated. |
