Issue 70

S.K. Shandiz et alii, Frattura ed Integrità Strutturale, 70 (2024) 24-54; DOI: 10.3221/IGF-ESIS.70.02

: Lagrange multiplier : variance of white noise : Dirac delta function : desired IMF frequency : Hilbert transform function : mass matrix of truck–trailer : damping matrix of truck–trailer : stiffness matrix of truck–trailer

λ   n 

H

T M T C T K

: node displacement : mass matrix of bridge : damping matrix of bridge : stiffness matrix of bridge

d

M

C K

: shape function

N

: interaction force at rear axle of truck : interaction force at front axle of truck

f 1 f 2 t f

: interaction force at trailer axle

f f f 1 2 3 ˆ , ˆ , ˆ

: forces due to inertia of truck–trailer and trailer axles : forces due to moment of rotational inertia of truck–trailer

f f 1 2 ,  

: vertical displacement : acceleration due to gravity

u

g

a b

: crack depth in damaged element

: beam height

b 1 , b 2 , b 3 c 1 ,c 2 ,c t1 c 3 ,c 4 ,c t2 k 1 ,k 2 ,k t1 k 3 ,k 4 ,k t2

: distance between axles

: damping of shock absorber between truck-trailer body and axles

: damping of wheels of truck-trailer

: stiffness of spring between truck-trailer body and axles

: stiffness of wheels of truck-trailer

I

: moment of inertia : mass moment of inertia

I 0

m 0

: mass of truck

m 1 , m 2 , m t1

: mass of axles of truck-trailer

m t0

: mass of trailer

L

: length of bridge span

f (t)

: original signal

E E’

: Elastic Modulus under normal conditions : Elastic Modulus in Plane Strain conditions

v

: Poisson’s ratio

G d (n)

: power spectral density function : stress intensity factors of modes

K I , K II , K III

: force due to weight : force due to inertia

R wk F wk

w ( , ) x t

: beam displacement in modal analysis

0 W 1 W

: strain energy of intact beam : strain energy of cracked beam

j 

: mode shape

j q

: generalized coordinate

: vehicle velocity

v

r(x), r’(x)

: Surface roughness function, derivative of surface roughness function

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