I don't know if the information I found below is true. . .
Cat path is a linear temporary construction access road erected under and parallel to the main cable during the construction of suspension bridge. It is a scaffold for constructors and a construction platform for the main cable system and even the whole superstructure of suspension bridge.
Catwalk during the construction of suspension bridge
Construction personnel have completed important work such as cable strand traction, cable strand adjustment, saddle shaping, cable tightening, cable clamp and sling installation, box girder hoisting and site connection, main cable winding and protective painting. There is one upstream and one downstream, and the cross section is usually U-shaped, long and narrow with some shaking, so it is called "cat path"
The design principle of catwalk should follow the principles of simple structure, convenient construction, safety, reliability, economy and rationality. The catwalk line shape should be parallel to the no-load line shape of the main cable and keep a certain distance; Minimize the dead weight and wind area; Safe and reliable operation, which can meet the requirements of working face, clearance, strength and stiffness required by mechanical operations such as cable traction and main cable tightening; At the same time, it is required that the installation and disassembly are convenient and fast, and the materials are economical, which is conducive to fire prevention. In addition, the catwalk cannot have additional influence on the tower, anchorage and main cable.
For details, please see: /view/2699 183.htm or
Summary of catwalk design of Peng long-span suspension bridge