Page - 1096 - in Book of Full Papers - Symposium Hydro Engineering

Despite the use of these triggers, an additional type of trigger will be defined to detect short time variations with more accuracy. Based on the fact that automated measurements are recorded each two hours, the hypothesis that between two consecutive measurements (at time i and time i-2h) small variations are expected can be considered adequate. In fact, the use of 3 as criteria regarding two consecutive automated measurements showed to be adequate, based on the records of manual and automated measurements, (this type of trigger is represented with the black colour in Fig. 7). Fig. 6 Synoptic example: Uplift pressures and discharges measured in the Baixo Sabor dam Fig. 7 Triggers used for the assessment of the uplift pressure measured in the piezometer PZ14 (126.6m) The final results for each trigger are presented in Table 4. 1096