| 摘要 |
PROBLEM TO BE SOLVED: To provide an expansion joint for a bridge allowing the state of cracks and breakage of a reinforcing steel plate to be surely recognized. SOLUTION: This expansion joint for a bridge is constituted by a compound member formed of rubber material G extending orthogonal to the axis of the bridge and the reinforcing steel plates 1, 2. The whole of the reinforcing steel plates 1, 2 is mostly covered with the rubber material G. A conductive line 4b is laid through a non-conductive layer along the surface pat extending from one end part to the other end part orthogonal to the axis of the bridge of the reinforcing plate 1, whereby when cracks are caused in the reinforcing steel plate 1, the conductive line 4b is cut at the above part so that the occurrence of the cracks in the reinforcing steel plate 1 can be recognized by confirming a resistance change between both ends of the conductive line 4b.
|
