APPARATUS FOR CONNECTING CONTINUOUSLY UPPER SLAB CONCRETES OF MULTI-SPAN PREFLEX COMPOSITE BRIDGE AND REPRESTRESSED PREFLEX COMPOSITE BRIDGE BY P.C STEEL WIRE P.C STEEL BAR

摘要

The subject innovation is then hypothesis independently on the steel I-girder with reinforced concrete or the same time PC strand or PC steel bar Beam the simple combination of the join each shift of the free flex beam or leaf Wrist rests free the flex beams of two or more span-span bridge , an upper slab of concrete in as cast-in-place so that each span is continuous, in the prior art, simple beam in each successive coupling points along the structural system to the switching to the continuous beam structural system such that each span a continuous during the construction load after the switching to the continuous beam structural system negative moment that acts on it is generated a tensile stress in the upper concrete slab. In this case typically the upper concrete slab of continuous attachment point is a crack in the concrete severely generated as a structure can not sufficiently resist the tensile stress had a structural problem in that gradual breakage.; In the present design is as shown in Figures 3 to 6 illustrate the drawing, the upper slab of concrete (3) in (continuous beam switching to the structural system old) continuous steel I-beam girders of each pair of simple bobim adjoining at the connection point for placing the after (1) depends on the support fixing portion to the upper flange (8) to pre-arranged for PC strand or PC steel bar (9) to control the initial stress of the upper slab of concrete (3) hameuroseo casting so that each span a continuous all, the tensile stress due to the negative moment of the continuous connection point P, Mr. strand or blood seed bar (9) there are no excessive tensile stresses and cracks resulting therefrom occurs top slab of concrete (3) of continuous connection point to be a burden are not or which are capable of inhibiting cracking within the allowable range is not free-span girder bridges flex synthetic blood, and said strands and f. providing a concrete upper slab continuous coupling device according to the said rod.