نوع مقاله : علمی - پژوهشی
نویسندگان
1 استادیار گروه مهندسی ژئوتکنیک و حمل و نقل، دانشکده مهندسی عمران، آب و محیط زیست، دانشگاه شهید بهشتی، تهران، ایران
2 دانش‌آموخته کارشناسی ارشد گروه مهندسی ژئوتکنیک و حمل و نقل، دانشکده مهندسی عمران، آب و محیط زیست، دانشگاه شهید بهشتی، تهران، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The main objective of the present numerical study is to investigate the seismic vulnerability of the caisson-type gravity quay walls with improved backfill soil located on a non-liquefiable dense seabed soil layer. In this regard, the effects of different improvement patterns applied to the liquefiable backfill on the seismic response of the wall are evaluated and compared. For this purpose, the Lagrangian explicit finite difference method and the UBCSAND constitutive model are utilized. First, a basic two-dimensional numerical model of the caisson quay wall is created and its response is validated against the corresponding experimental observations. Afterward, by performing non-linear time history dynamic analysis under the effect of various seismic events with different risk levels, 11 series of probabilistic seismic fragility curves are developed within the performance-based design framework for the caisson quay walls with 10 different backfill improvement patterns and also for the caisson quay wall without improvement. According to the damage probability of the wall with various improvement patterns at different seismic levels as well as the area of the improved zone behind the wall, the effectiveness and efficiency of the proposed improvement patterns on enhancing the seismic performance of the system are evaluated and discussed. The results show that the backfill replacement and modification improve the seismic performance of the wall and reduce its vulnerability in all seismic levels. By applying different backfill improvement patterns, the permanent horizontal displacement at the top of the wall after earthquake decreases on average between 40% and 73% compared to the wall without improvement. The triangle and trapezoidal geometrical patterns with the base at the bottom have the most positive effect on reducing both the horizontal displacement of the wall and the possibility of its seismic damage.
کلیدواژه‌ها [English]
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