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Bridge expansion and contraction problems

Jul 23, 2015

Due to changes in ambient temperature, steel cable tray for expansion and contraction of the phenomenon. Outdoor bridge temperature environment and a maximum temperature of 40 degrees Celsius, the lowest temperature is-20 degrees, the maximum shrinkage of cable tray evaluated according to the following formula:

Δ t=11.2x10-6x60deg (degrees) x1000mm

In conclusion:

Temperature at 60 ℃, δ ι =0.672mm/m

When the temperature is 50 c, δ ι =0.560mm/m

When the temperature is 40 c, δ ι =0.448mm/m

Straight segments to cable trays should be taken into account in the design of expansion joints, expansion joint spacing recommendations the following determination:

When the temperature is 40 degrees 50m;

When the temperature is 50 c for 40m;

When the temperature at 60 ℃, 40m.