Dear All,

Can we consider the weight of the truck on the underground piping while crossing the road in Caesar s/w? Kindly advise.

Regards

Have a look in standard ALA, there are many books regarding underground calculation.

There are two issues with the weight of the truck:
- stresses in circumferential direction (ovalisation of the pipe). This is not included in CAESAR II because CAESAR II uses beam elements. This check can be done using for example AWWA guidelines.
- stresses in longitudinal direction. Due to the local heavy load the pipe and soil will have more vertical displacement in that area, thus creating extra longitudinal/bending stresses in the pipe. Placing a force in your CAESAR II model can maybe represent this load case. However I have never tried that because most of the time only the AWWA check is done. I know there are exceptions where also the extra longitudinal stress is checked. But I think that is a completely seperate topic.

Loads on Pipe buried under roadways or railroad tracks are covered in AWWA. There are formulas and procedures that calculate the deflection on the pipe and acceptance based on less than 2% deflection. IT CANNOT BE SIMULATED ACCURATELY WITH CAESAR II. Some of the parameters involved include type of fill, depth and width of trench, compaction of trench bed etc.

For oil and gas pipelines, refer to API RP 1102 "STEEL PIPELINES CROSSING RAILROADS AND HIGHWAYS" to check the hoop stress on pipe due to external loads. Sharpen your pencil and prepare your calculator to do your manual checking.

Hi!
What is AWWA shortcut for?
I supposed that is standard, but I couldnt find it.
Thanks all!

American Water Works Association

google it (A.W.W.A not AWWA)or visit www.awwa.org

for underground pipe live load, you can use
1, ALA
2, AISI AWWA M11,
3, PPI (Handbook of Polyethylene pipe of the plastic pipe institute)
4, CEPA equation (Warman Hart and Francini, 2009)
5, CSA S6-10 CHDB (Canadian Highway Bridge Design Code)
6, API RP1102
7, American Association of State Highway and transportation officials design Guide,
each method has their own focus,