AASHTO HB-17 DIVISION I-A SEC 2-2002 Division I-A Seismic Design - Symbols and Definitions《抗振设计-符号和定义》.pdf

1、Section 2 SYMBOLS AND DEFINITIONS 2.1 NOTATIONS The following symbols and definitions apply to these Specifications: = Vertical spacing of transverse reinforcement (hoops or stirrups) in rectangular reinforced concrete = Acceleration coefficient determined in Article 3.2 (dimensionless) = Area of re

2、inforced concrete column core (in2 or mm2) = Gross area of reinforced concrete column (in2 or mm2) = Area of longitudinal reinforcement in a concrete pile (in.2 or mm2) = Total cross-sectional area of transverse reinforcement (hoops or stirrups) used in rectangular rein- = Total amount of reinforcem

3、ent normal to a construction joint (in2 or mmz) = Loads resulting from buoyancy forces and used in the group load combinations of Equations (6-l), = Coefficient used in steel design to account for boundary conditions (dimensionless) = Elastic seismic response coefficient defined in Article 3.6.1 (di

4、mensionless) = Elastic seismic response coefficient for mode ?m? defined in Article 3.6.2 (dimensionless) = Diameter of a reinforced concrete column (in. or mm) = Loads resulting from dead load and used in the group load combinations of Equations (6-l), (6-2), = Loads resulting from earth pressure a

5、nd used in the group load combinations of Equations (6-l), = Modified foundation seismic forces used in the group load combination of Equations (6-2) and (7-2), = Modified seismic forces used in the group load combination of Equations (6-1) and (7-l), and de- = Specified compressive strength of rein

6、forced concrete (psi or MPa) = Yield strength of reinforcement in reinforced concrete members (psi or MPa) = Yield strength of transverse reinforcement (psi or MPa) = Axial stress in steel design that would be permitted if axial force alone existed (psi or MPa) = Buckling stress for load factor stee

7、l design (psi or MPa) = Euler buckling stress in the plane of bending (psi or MPa) = Euler buckling stress for service load steel design (psi or MPa) = Yield strength of structural steel (psi or MPa) = Acceleration of gravity (in./sec2 or cm/sec2) = Core dimension of a rectangular reinforced concret

8、e column (in. or mm) = Height of a column or pier defined in Articles 5.3,6.3, and 7.3 (ft or m) = Importance Classification given in Article 3.3 (dimensionless) = Total lateral stiffness of bridge as defined in Article 4.3 (lb/in. or kN/m) = Effective length factor used in steel design and given in

9、 Articles 6.5 and 7.5 (dimensionless) = Seismic coefficient used to calculate lateral earth pressures and defined in Articles 6.4.3 and 7.4.3 columns (in. or mm) forced concrete columns (in.2 or mmz) and defined by Equations (6-6), (6-7), (7-6), and (7-7) (6-2), (7-l), and (7-2) (7-l), and (7-2) (6-

10、2), (7-l), and (7-2) and defined in Articles 6.2.2 and 7.2.1 fined in Articles 6.2. l and 7.2. l (dimensionless) 445 446 HIGHWAY BRIDGES 2.1 L N Pe(x Pn Po Q R S S SF SPC T Tm vc Vj “U VU v,(x), v,(x) w(x) W Ph Pn Ps 4) a Y = Length of bridge deck defined in Articles 4.3, 5.3,6.3, and 7.3 (ft or m)

11、= Minimum support length for girders specified in Articles 3.10, 5.3,6.3, and 7.3 (in. or mm) = Intensity of the equivalent static seismic loading applied to represent the primary mode of vibration = Minimum axial load specified in Article 7.2.3 for columns and 7.2.4 for piers (lb or N) = Assumed un

12、iform loading used to calculate the period in Articles 4.3 and 4.4 (forcelunit length) = Vertical force at a support due to longitudinal horizontal seismic loads (lb or N) = Response modification factor specified in Article 3.7 (dimensionless) = Site coefficient specified in Article 3.5.1 (dimension

13、less) = Angle of skew of girder support as defined in Articles 5.3 and 6.3 (degrees) = Loads resulting from stream flow forces and used in the group load combinations of Equations (6-l), = Seismic Performance Category specified in Article 3.4 (dimensionless) = Fundamental period of the bridge determ

14、ined in Articles 4.3 and 4.4 (sec.) = Period of the mth mode of vibration of a bridge (sec.) = Nominal shear strength provided by concrete as specified in Article 7.6.2(C) = Limiting shear force across a construction joint (lb or N) = Shear stress (psi or MPa) = Shear force (lb or N) = Static displa

15、cement profiles resulting from applied loads po and pe, respectively, and used in Articles = Dead weight of the bridge superstructure and tributary substructure per unit length (forcelunit length) = Total dead weight of bridge superstructure and tributary substructure (lb or kN) = The ratio of horiz

16、ontal shear reinforcement area to gross concrete area of a vertical section-Article = The ratio of vertical shear reinforcement area to the gross concrete area of a horizontal section- = Volumetric ratio of spiral reinforcement for a circular column (dimensionless) = Strength reduction factor (dimen

17、sionless) = Coefficient used to calculate the period of the bridge in Article 4.4 (length2) = Coefficient used to calculate the period of the bridge in Article 4.4 (force length) = Coefficient used to calculate the period of the bridge in Article 4.4 (force * length2) in Articles 4.3 and 4.4 (forcelunit length) (6-2), (7-l), and (7-2) 4.3 and 4.4 (in. or mm) 7.6.3 (dimensionless) Article 7.6.3 (dimensionless)