بررسي رفتار ديناميكي سكوهاي ثابت فلزي دريايي در حالت نصب عرشه با روش شناور سازي با استفاده از روش تحليل ديناميكي افزايشي (يادداشت فني)

NONLINEAR DYNAMIC BEHAVIOR OF FLOAT OVER DECK INSTALLED PLATFORMS USING INCREMENTAL DYNAMIC ANALYSIS

Incremental Dynamic Analysis (IDA) is a parametric analysis method that has recently emerged in several different forms to estimate more thoroughly structural performance under seismic loads. It involves subjecting a structural model to one (or more) ground motion record(s), each scaled to multiple levels of intensity, thus producing one (or more) curve(s) of response parameterized versus intensity level. Of great interest in Performance-Based Earthquake Engineering (PBEE) is the accurate estimation of the seismic performance of structures, and in particular, the mean annual frequency (MAF) of exceeding a specified structural demand or a certain limit-state capacity. In this study the behavior of a jacket type offshore platform with different characteristics in its two directions, separately and with 3D modeling considering pile-soil-structure interaction is investigated. By obtaining the IDA curves and summarizing the results, the behavior of the jacket is studied. All analyses are performed using OpenSees software. It is observed that the difference of geometry of jacket in two directions due to employing Float Over Deck (FOD) installation method, does not cause similar behavior in both directions and finally in direction with float over installation design requirement is not satisfied.