<< Previous | Contents | Next >> |

## Guide for Heat-Straightening of Damaged Steel Bridge Members

### Appendix II: Nomenclature

a,b,c = Dimensional constants

b_{f} = Flange width

b_{s} = Width of stiffening element

C = Temperature in degrees Celsius

c_{d} = Chord length across the yield zone of a curved beam

d = Depth of wide flange beam or primary plate element

d_{s} = Distance between the vee apex edge of the primary plate element and the
stiffening element

d_{v} = Depth of vee in flat plate

E = Modulus of elasticity

f_{a} =
Axial stress in a compression member due to live and dead loads

F_{a} = Stress factor for calculating
plastic rotation in rolled shapes

F_{} = Jacking load factor

F_{s} = Shape factor for calculating
plastic rotation in rolled shapes

F_{y} = Yield stress

_{} = Span length of flexural member

L, L_{r} = Lengths between offsets

L_{u} =
Length of free edge of flange before localized damage

M_{j} = Moment
produced by jacking forces

M_{p} = Plastic
moment capacity of a member

M_{r} = Residual moment

M_{y} = Moment at initial yield

n = Number of single vee heats required to remove a specified amount of damage

P = Axial load in compression member

P_{a} = Total jacking force for an axially loaded member

P_{ec} = Additional jacking force required to cancel eccentric moments due to axial loads

P_{j} = Jacking force

P_{n}, P_{f} = Jacking force on near and far side of locally damaged flange

r = Radius of arbitrary circle on flange bulge

R = Actual radius of curvature

R_{} = Jacking ratio *M _{j} / M _{p}*

R_{y} = Radius of curvature at initial yield

S = Section modulus

T = Heating temperature

t_{w} = Web thickness

V = Width at open end of vee

W = Primary plate element width

y_{o} =
Initial out-of-straightness of compression member

y_{r} = Measured offsets at point r

y_{max} = Distance from centroid to extreme fiber

Z = Plastic section modulus

α = Coefficient of thermal expansion

δ_{f}, δ_{n} = Deflection of locally damaged flange on far and near side, respectively

a = Coefficient of thermal expansion

δ_{max} = Maximum deflection of laterally loaded beam

Δ = Lateral deflection of loaded member

ε = Actual strain

ε_{e} = Elastic strain at open end of vee

ε_{max} = Actual strain at extreme fiber of member

ε_{y} = Strain at initial yield of material

γ = Distribution factor for heated composite beam

μ = Ratio of maximum strain to yield strain, ε_{max}/ε_{y}

φ_{b} = Basic plate rotation factor

φ_{c} = Plastic rotation of composite girder

φ_{d} = Degree of damage

φ_{p} = Plastic rotation resulting from a single vee heat on a plate or rolled shape

θ = Vee angle

θ_{f} = Slope of flange on side away from impact for locally damaged member

θ_{n} = Slope of flange on impact side of locally damaged flange

θ_{w} = Slope of web for beam with local flange damage

<< Previous | Contents | Next >> |