Static downbearing reaches the piano soundboard through the bridges; the resulting structural state reflects both broad panel bending and local redistribution around ribs and other stiffness transitions. To examine these two response scales, a three-dimensional linear-static finite-element model of the soundboard-rib-bridge assembly of a UH121 upright piano was built in ANSYS Workbench. The global Z component of the full-string downbearing was mapped onto the bridge regions. Every one of the 438 source load points was transferred, and the source and target Z-resultants were both ？6413.5 N. Maximum total deformation was 1.4251, 1.5045, and 1.4551 mm for the coarse, baseline, and fine meshes, respectively; none differed from the fine-mesh value by more than 3.40%. In the baseline model, Z displacement extended from ？1.5045 to 0.01265 mm. The maximum and minimum principal stresses reached 17.894 and ？22.151 MPa, and the corresponding principal elastic-strain extrema were 1264.4 and ？1420.2 με. The strongest local responses occurred near the bridges, ribs, bridge-rib neighborhoods, and constrained perimeter, rather than at the point of maximum displacement. Electrical strain measurements located a high-response region in a bridge-rib neighborhood, providing qualitative experimental support for the spatial pattern predicted by the model. The soundboard response was consequently characterized by global Z-direction bending superimposed on local load redistribution: the bridges introduced the load, whereas the panel and ribs carried it toward the surrounding structure. This static description can support subsequent assessment of upright-piano soundboards and rib configurations.
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