Issue 40

Z. Zhang et alii, Frattura ed Integrità Strutturale, 40 (2017) 149-161; DOI: 10.3221/IGF-ESIS.40.13 155 Figure 5 : Load and temperature monitoring system. a SPA10 b SPA15 c SPA20 d SPA25 Figure 6 : Hysteresis curves of dampers for SPA with different opening ratios. R ESULTS AND DISCUSSION Hysteretic curve and the skeleton hysteresis curve he hysteretic curve for a component or a structure is a very important and comprehensive indicator that could represent the earthquake resistance performance as well as a good judgement for structural elasto-plastic analysis. The hysteretic curves for the four different opening ratios are shown in Fig.6, in which SPwith displacement load as x-axis and bearing capacity as y-axis. As shown in this figure, all the four curves are very full as well as the stiffness degeneration (cyclic softening) occurs due to damage. Also, by comparing the four curves, we could see that the stress concentration is more and more severe while the maximum bearing capacity is becoming smaller as the opening ratio goes larger. The stiffness degeneration of damper with opening ratio of 25% is minimum in the four tests, which is because of -10 -8 -6 -4 -2 0 2 4 6 8 10 -80000 -60000 -40000 -20000 0 20000 40000 60000 80000 Hysteresis curve Bearing curve （ ） Load N （ ） Displacement mm -10 -8 -6 -4 -2 0 2 4 6 8 10 -80000 -60000 -40000 -20000 0 20000 40000 60000 80000 （ ） Load N （ ） Displacement mm Hysteresis curve Bearing curve -10 -8 -6 -4 -2 0 2 4 6 8 10 -80000 -60000 -40000 -20000 0 20000 40000 60000 80000 Hysteresis curve Bearing curve （ ） Load N （ ） Displacement mm -10 -8 -6 -4 -2 0 2 4 6 8 10 -80000 -60000 -40000 -20000 0 20000 40000 60000 80000 Hysteresis curve Bearing curve （ ） Load N （ ） Displacement mm T