Seite - 792 - in Book of Full Papers - Symposium Hydro Engineering

The other frequencies, however, presented well-formed and expected behaviors, comparable to results obtained in test models in Ansys. Thus, the analyzes with variable section are also only done for the frequencies of the second to the fifth mode. For the case of variable cross-section, it is analyzed various relations h/L, being h the height of the base cross-section of the beam (or dam base width in plane strain state) and L the length of the beam (or dam height in plane strain state). The top cross-section height is fixed as half of the base cross-section (Figure 5). Figure 5: Geometric values used in the variable cross-section study. The results for the variable cross-section case are presented in the Figure 6. Figure 6: Parametric results for a cantilever beam with variable cross-section. Comparing the results of variable cross-section with those for constant cross- section, presented in Figure 4, it is observable that the variable cross-section induces higher ratios, i.e. the Timoshenko effects tend to be slightly less present. For the same h / L ratio, the frequency ratios for all modes are higher for a variable cross-section than for the constant cross-section case. 792