Hi fellow pipe stressers,

I was wondering if I can pick you brain for the below DN150 STD CS piping system which has a portion buried 1.5m underground as shown in the attached pic.
Delta temperature for buried piping is 45 deg C. The lengths of the buried portions are marked up in red. From CII buried module, the VAL calculated is about 15 m.
I modelled the whole system as shown below and had thermal overstress issues on every bends which are expected. However the overstress issue still exists (about 140%) even with large dia bend up to 20D on most bends.
My question is, have I done the correct approach on modelling the whole buried piping as shown below? Is the thermal overstress of over 300% using LR elbows to be expected in such buried piping arrangement? What's the best way to model this buried piping / Or is it acceptable to just model the straight length of 30m (2 x VAL) from AG/UG points? Thanks for any input you may have.

Daprin