The invention seismic for enhancing the fastening force of the road with the structure, having used to secure the expansion joints, etc., which is installed on top of the joint, such as railroad structures and ballast prevent loosening of the bolts due to vibration, pressure, and bolt It relates to an anchor bolt.
A preferred embodiment of the present invention includes a bolt head of the cone being the upper surface is flat and the cross section reduced toward the lower dish-shaped, bolt protruding to the lower portion of the head is composed of a main body, the threads formed on the outer circumferential surface the flat head bolt with .; Consists of a ring-shaped through-hole is formed in the central portion, is formed with a receiving groove corresponding to the bolt head of the flat head bolt in the top surface, the body of the washer and the flat head bolt is inserted into the through-hole configuration; The rubber ring is fitted to the main body of the flat head bolt which is located in the lower portion of the washer; A cylindrical shape that the threads are formed on the hollow form and the inner peripheral surface to the inside, is stepped is formed inside a predetermined height of the hollow is formed to have a lower part wider cross section than the hollow upper portion around the stepped, countersunk in an upper portion of the hollow and the cap nut of the bolt body is coupled to the bolt; Seismic spring top end is caught by the bottom of the hollow of the cap nut so as to take a stepped configuration and; Comprises a; tongued, grooved, rebated bolt is bolted to the bottom of the cap nut.