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.