DESIGN SPECIFICATIONS FOR HIGHWAY BRIDGES - IISEE

14.3 Reinforced Concrete Superstructure
14.3.1 Strength and Displacement Capacity
Ultimate strength and allowable displacement of a concrete superstructure in the
plastic range shall be determined by either experimental results or appropriate
analytical results. These values shall be obtained in terms of limit states of the
superstructure specified in Sections 5.3 and 5.4.
14.3.2 Structural Details
(4) Reinforcements in a concrete superstructure shall be placed by properly selecting
splice structures, and configuration and arrangement of lateral bars, in
consideration of the plastic range estimated in Reinforced Concretemembers.
(5) Bearing supports of a concrete superstructure subjected to horizontal forces
transmitted from bearing shoes and unseating prevention structures shall be
designed in accordance with the provisions in Section 18.2 of Part III Concrete
Structures.
14.4 Ends of Superstructure
14.4.1 Gap between Two Adjacent Girders
(6) In the design of the ends of the superstructure, necessary gap between the ends of
two adjacent girders shall be taken for preventing a collision between two
adjacent superstructures, a superstructure and an abutment, or a superstructure
and the truncated portion of a pier head, when subjected to Level 1 and Level 2
Earthquake Ground Motion. In particular, for seismically-isolated bridges,
sufficient spacing of adjacent girders shall be provided at the ends of
superstructures, in order to ensure the expected effects of seismic isolation.
However, in design of a normal bridge other than seismically-isolated bridges, the
gap between the ends of two adjacent girders can be determined by considering
that the collision does not happen for Level 1 Earthquake Ground Motion, if a
verification confirms that the collision will not affect the sound seismic
performance of the bridge when subjected to Level 2 Earthquake Ground Motion.
74