Abstract: In order to design an infrastructure of an elevated bridge, first a target ductility factor &mgr;d and target natural period Td for the infrastructure are set in connection with an assumed earthquake motion. Subsequently, a yield seismic coefficient for the target ductility factor &mgr;d and target natural period Td is obtained from a yield seismic coefficient spectrum for the assumed earthquake motion as a design seismic coefficient Kh. On the other hand, a target yield rigidity Kd corresponding to the target natural period Td is obtained. Subsequently, the design seismic coefficient Kh is used to obtain a design horizontal load bearing capacity Hd and a displacement corresponding to the design horizontal load bearing capacity Hd is obtained as a design yield displacement &dgr;d from the target yield rigidity Kd. Subsequently, the design horizontal load bearing capacity Hd is distributed into a horizontal force Hf to be borne by the RC rigid frame and a horizontal force Hb to be borne by the damper-brace.

Abstract: A reinforced concrete frame is seismically reinforced by cutting a main reinforcement bar of a reinforced concrete member so as to shift a failure property of the reinforced concrete member from a shear failure preceding type to a bending failure preceding type.

Abstract: A method for designing a seismic frame. Models of a reinforced concrete rigid frame and a seismic frame structure, respectively, are provided. Based on distances between components and damper load displacement in the seismic frame structure model, a burden (Prc) for the reinforced concrete rigid frame is calculated. A section design of the seismic frame structure is performed according to the elasto-plastic analyses.

Abstract: In order to design an infrastructure of an elevated bridge, first a target ductility factor &mgr;d and target natural period Td for the infrastructure are set in connection with an assumed earthquake motion. Subsequently, a yield seismic coefficient for the target ductility factor &mgr;d and target natural period Td is obtained from a yield seismic coefficient spectrum for the assumed earthquake motion as a design seismic coefficient Kh. On the other hand, a target yield rigidity Kd corresponding to the target natural period Td is obtained. Subsequently, the design seismic coefficient Kh is used to obtain a design horizontal load bearing capacity Hd and a displacement corresponding to the design horizontal load bearing capacity Hd is obtained as a design yield displacement &dgr;d from the target yield rigidity Kd. Subsequently, the design horizontal load bearing capacity Hd is distributed into a horizontal force Hf to be born by the RC rigid frame and a horizontal force Hb to be born by the damper-brace.

Abstract: In order to design an infrastructure of an elevated bridge, first a target ductility factor &mgr;d and target natural period Td for the infrastructure are set in connection with an assumed earthquake motion. Subsequently, a yield seismic coefficient for the target ductility factor &mgr;d and target natural period Td is obtained from a yield seismic coefficient spectrum for the assumed earthquake motion as a design seismic coefficient Kh. On the other hand, a target yield rigidity Kd corresponding to the target natural period Td is obtained. Subsequently, the design seismic coefficient Kh is used to obtain a design horizontal load bearing capacity Hd and a displacement corresponding to the design horizontal load bearing capacity Hd is obtained as a design yield displacement &dgr;d from the target yield rigidity Kd. Subsequently, the design horizontal load bearing capacity Hd is distributed into a horizontal force Hf to be borne by the RC rigid frame and a horizontal force Hb to be borne by the damper-brace.

Abstract: In order to design an infrastructure of an elevated bridge, first a target ductility factor &mgr;d and target natural period Td for the infrastructure are set in connection with an assumed earthquake motion. Subsequently, a yield seismic coefficient for the target ductility factor &mgr;d and target natural period Td is obtained from a yield seismic coefficient spectrum for the assumed earthquake motion as a design seismic coefficient Kh. On the other hand, a target yield rigidity Kd corresponding to the target natural period Td is obtained. Subsequently, the design seismic coefficient Kh is used to obtain a design horizontal load bearing capacity Hd and a displacement corresponding to the design horizontal load bearing capacity Hd is obtained as a design yield displacement &dgr;d from the target yield rigidity Kd. Subsequently, the design horizontal load bearing capacity Hd is distributed into a horizontal force Hf to be borne by the RC rigid frame and a horizontal force Hb to be borne by the damper-brace.

Abstract: In order to design an infrastructure of an elevated bridge, first a target ductility factor &mgr;d and target natural period Td for the infrastructure are set in connection with an assumed earthquake motion. Subsequently, a yield seismic coefficient for the target ductility factor &mgr;d and target natural period Td is obtained from a yield seismic coefficient spectrum for the assumed earthquake motion as a design seismic coefficient Kh. On the other hand, a target yield rigidity Kd corresponding to the target natural period Td is obtained. Subsequently, the design seismic coefficient Kh is used to obtain a design horizontal load bearing capacity Hd and a displacement corresponding to the design horizontal load bearing capacity Hd is obtained as a design yield displacement &dgr;d from the target yield rigidity Kd. Subsequently, the design horizontal load bearing capacity Hd is distributed into a horizontal force Hf to be borne by the RC rigid frame and a horizontal force Hb to be borne by the damper-brace.

Abstract: To provide inexpensively a connector constructed of a steel pipe and bearing a tie function of a ladder-type sleeper for railway tracks, in a connector constructed of a steel pipe 1 used in the ladder-type sleeper for railway tracks integrated with longitudinal beams made of concrete and the connectors constructed of steel pipes 1 by feeding concrete, both end portions of the connector constructed of the steel pipe 1 are flattened in the horizontal direction and a corrosion resistant coating 4 is coated at portions of the connector constructed of the steel pipe 1 exposed to the atmosphere.

Abstract: The present invention comprises longitudinal beams provided on the underside of each of a pair of rails in the longitudinal direction of the rails and multiple connectors which mutually connect these longitudinal beams at designated spacings along the longitudinal direction. Because the ladder-type sleepers of the present invention have a structure wherein longitudinal beams are continuously positioned along the longitudinal direction of the rails, the bending stiffness of the track frame in the longitudinal direction increases, and the ballast pressure is reduced by improving the distribution of the train load. As a result, it is possible to reduce track irregularities resulting from the repeated burden of the train load.

Abstract: A side-wall beam is installed on a base for a guideway for a magnetic levitation vehicle. An elastic body is interposed between the side-wall beam and the base. Then, the side-wall beam is fastened to the base with a tendon on an imaginary line which extends through an intermediate portion of the elastic body in the transverse direction of the side-wall beam and which extends along the longitudinal direction of the side-wall beam. The elastic body is thereby held under compression between the side-wall beam and the base. The side-wall beam is supported on the base through the elastic body, and also fastened to the base, holding the elastic body under compression between the side-wall beam and the base. Reactive forces produced by the compression of the elastic body act to resist forces tending to cause the side-wall beam to fall over. Any displacement of the side-wall beam which may be caused by forces generated when the magnetic levitation vehicle passes can thereby be kept within a predetermined range.