Due to changes in ambient temperature, the steel cable tray will expand and contract with heat. The outdoor bridge is greatly affected by temperature. For example, the maximum ambient temperature is 40°C and the minimum temperature is -20°C, then the maximum shrinkage of the cable tray is calculated as follows:
Δt=11.2 ×10-6×60deg(degree)×1000mm
This leads to the conclusion:
When the temperature difference is 60℃, Δι =0.672mm/m
When the temperature difference is 50℃, Δι =0.560mm/m
When the temperature difference is 40℃, Δι =0.448mm/m
In engineering design, expansion joints should be considered for cable trays in straight sections, and the spacing of expansion joints is recommended to be determined as follows:
50m when the temperature difference is 40℃;
40m when the temperature difference is 50℃;
