This thread started out advising the readers the pipe had (underlying?) "guides" in the vicinity of an arrangement of off-setting bends, and the figure later supplied appeared to depict the problematic guides were underground. A later comment of the OP stated an apparent different or concurrent function of the supports i.e. to "limit the settling" of the pipeline in "muskeg".
In any case, pipe have of course been supported on intervals for hundreds of years, more commonly aboveground, but also in many cases over the years in unstable soil masses as well. However, the pipe, as well as contact points and the support itself, must be sufficiently strong to take the loads imposed (as well as stiff enough to prevent objectionable deformation). High localized stresses and/or deformation can occur at supports when thin or weak pipes are supported at relatively unyielding, flat supports (i.e. where the contact area may be near infinitely/VERY small) and particularly underground.
I believe all manners of ground and pipeline behaviors, in addition to vertical settlement of the soil and pipe mass (or flotation, if e.g. a line lighter in bulk density than that of the OP is strapped down in liquefaction incidents) of the pipe and soil mass, can contribute to localized loads/reactions. Examples of perhaps further complicating behaviors would be the effects of e.g. at least slight Bourdon (extension) movements of the piping due to thrust at bends near the supports, as well as thermal expansion/contraction etc. In the case of the figure configuration, it would appear even slight thermal expansion and outward and downward thrust forces due to internal pressure would (pivot the riser to a some longer vertical elevation difference and) perhaps press the pipe barrel even more tightly against the nearest support plate as the upbend at the bottom tried to move downward? [Also, what is the span of the piping both between the supports or guides as well as outside of the two supports depicted, that were to "limit the settling" in the muskeg, is there any traffic over the area, and could/do ice lenses form over the line between same and the surface in the winter?]
I think some background of and reference to pipe on supports and research involving same, particularly to calculate maximum localized stress once reaction loads are defined, can be found in many past threads, e.g.
