What Does
Live Load Mean?
A live load can be defined as those loads that aren't constant unlike dead loads. Live loads exert pressure on the pipe for a moment of time and have less effect on the pipe performance unless the pipe is buried at shallow depth. Live load is contributed by moving traffic on highways, railways and airports or even falling objects. These loads are not constant and change in magnitude and cannot be determined with accuracy.
Trenchlesspedia Explains Live Load
A live load can be determined in two ways. One is by using a standard table that gives the values of vertical loads that are a function of pipe depth and road types, after applying a safety factor that covers the impact effects of the loads. The other is by applying a formula:
Pp = [3Ps / { 2Πc² [1+(d/c)²]2.5 }] Fimpact
Pp – exerted pressure on the pipe
Ps – concentrated load on surface
C – soil height above pipe
d – distance from pipe center to concentrated load on the surface
Fimpact – Impact factor
A pipe that has been buried deep in the soil with good side support and adequate and well compacted backfill will be able to withstand live loads considerably well.