Dear all,
In ASME B31.3 PARA 319.2.1D mentioned about Total Strain Displacement that include thermal displacement, reaction displacement and displ due to external load, where all of these should consider together.
My intrepetasion of reaction displacement is Displ. Due to reaction load such as slug load and others. If my intrepetation correct, it mean we can add slug load (F1) with another occ load (ex: wind) so that become:
W+T1+P+F1+WIN1
W+T1+P+F1+WIN2
And so on (for slug load with wind)..
For combination with seismic will be the same only wind and seismic will never occur together.
The problem if I have 14 Slug load to be considered, the load cases will be so many...
Does my intrepetation correct..
In previous project I seperate the load case to analysis slug load alone. Only when I read paragraph 319.2.1d in ASME B31.3 2010 I become not sure.
Can someone throw an opinion on these topic, please, I will appreciate it so much.
Thank you.

Wind, slug and (the inertial component of) seismic load are all force-based rather than strain-based loads. These force-based loads are controlled by system collapse or yield. Strain-based loads are controlled by fatigue.
In my opinion, your interpretation is not correct.

Can somebody elaborate the statement made by Dave with respect to this topic

I agree with Dave. Strain-based loads are created by deflection of the terminal points of the piping system due to externally applied deflections. Slug flow loads are created by the impact of piping fluids.

An analogous situation in terms of everyday things would be opening and closing a door by releasing the latch and imposing a displacement on the doorknob vs. opening the door by running full speed at the center of the door and hitting it with your shoulder.

Strain-based loads cause reversible deflections, slug flow loads don't.

Hello friends,

I think incremental Cyclic Growth due to Repeated Loads failures where loads that do not repeat, act with loads that do repeat, such that progressive plastic deformation (ratcheting) occurs. The actual failure path caused by ratcheting is difficult to visualize. The typical ratcheting model involves an axial, non-repeating stress, with a superimposed repeating bending stress. The combination of a repeated bending stress and non-repeated axial stress produces a plastic deformation in the outer fibers that increases with each application of the bending load.
The Shakedown limit only uses the cyclic repeated loadings. But the ratcheting limits include primary, (non-cyclic) loadings combined with secondary (cyclic) loadings.
So, ASME B31.3 PARA 319.2.1D addresses these considerations and requirements.