Single plane or multiple planes use in cable-stayed bridges

Question

Explain the single plane or multiple planes use in cable-stayed bridges?

Answer 1

The necessity of high torsional stiffness of bridge deck is essential to improve proper transverse load distribution for one cable plane to be adopted. It possesses large capacity for load spreading. So, it helps in avoiding major stress deviation in the stay and leads to low fatigue loading of cables.
Three cable planes are usually adopted so as to reduce the transverse bending moment in case of very wide bridge.