A	cross-section area
d	distance between stay cables
E	Young’s modulus
f	rise of the main cable
h	height of the pylon
I	inertia moment
M	function for bending moment
L b	length of the side span
L m	length of the main span
Ls	length of the suspension part
P	concentrated load on the bridge
q	uniformly distributed load on the bridge
t 1	membrane tension of hangers
t 2	membrane tension of stay cable on main span
t 3	membrane tension of stay cable on side span
w	function for deflection
Δf	elongation of the hanger
π	function for potential energy
θ	inclination angle of the stay cable