Appendix, Image 7 shows lines of equal displacements in the global direction X (Appendix Image 1) for the load case of hydrostatic stress. The load case of self-weight was excluded, because control measurements can only be made after the construction is completed.
One can observe that the dam crest is slightly raised as a result of the hydrostatic stress. This phenomenon can be explained with Poisson's lateral strain, which is caused by horizontal compressive stress from the arching effect.
Appendix, Image 8 shows the shapes of the original and the deformed element meshes. The magnification factor is 1000. This image does not provide quantitative insight, but it helps to better understand the global behaviour of an arch dam.