Evolutionary (pinching Clause Samples

Evolutionary (pinching system‌ The first example of model calibration refers to a PIN-SDOF system of the type in Figure 2 (right). Weight is 100 kN and the yielding force ( F1 ) is equal to 12.25 kN, which corresponds to a strength reduction factor equal to 4 when the mass acceleration is equal to 0.49g; drift at the yielding is equal to 0.76%. {F2 , F3, x2 , x3} the parameters of Figure 2 are equal to {13.8 kNm,1.38 kNm, 0.0175 rad , 0.1 rad}, respectively; the unloading/reloading rules are from [15]. The described Monte Carlo simulation approach was followed to get the Pi , j transition probabilities in one event. Indeed, an illustrative example (realization) of a complete simulated sequence of events, leading the structure to travel from AN conditions to F damage state, is shown in Figure 8. The sequence features about nine-hundreds sampled intensities and ground motions.5 Transition to the IO state occurs during the fourth record while, due to the 749th, 840th and 868th extracted intensities and consequent ground shaking, the SDOF reaches LS, CP and F, damage states, respectively. Total hysteresis after each state transition, is also reported in the picture. In the case of the PIN systems, a total of sixty seismic sequences have been simulated. Given that the structure is in damage state i, the probability the structure moves to a damage state j, (i +1 ≤ j ≤ n) , in one event, Pi, j , is estimated via the ratio of the number of transitions between the states and the number of sampled IM values when the structure was in state i. Then the Pi, j probabilities are used in conjunction with the annual occurrence rate of events at the site to get the annual transition matrix of Equation (8), as per Table 2. Note that, in this case the annual rate of earthquakes is much larger than one, being