الگوهاي شكل مناسب براي سدهاي قوسي درمناطق زلزله‌خيز

Optimum patterns for arch dam shape design in highly seismic zones

طراحي ايمن سازه‌هاي حساسي مانند سدهاي بتني قوسي در كشور فوق‌العاده لرزه‌خيز ما داراي اهميت خاصي است. ازآنجاكه طراحي شكل اين سد‌ها عملكرد سازه‌اي آن‌ها را به شدت تحت تاثير قرار مي‌دهد، در پژوهش، معرفي الگوهاي شكل سد‌هاي قوسي كارآمد در مناطق لرزه‌خيز و شناسايي گرايش‌ها و ويژگي‌هاي حاكم بر شكل اين سد‌ها با توجه به تغييرات شرايط فيزيكي و هندسي ساختگاه به كمك روش‌هاي نوين بهينه‌سازي رياضي شكل سازه مورد نظر قرار گرفته است. روش انجام پژوهش به صورت انجام محاسبات پارامتريك و آماري (رگرسيون خطي) برروي تعداد زيادي نمونه سد قوسي است. به اين طريق كه تعداد زيادي نمونه سد قوسي با شرايط مختلف از نظر ارتفاع، عرض دره، مدول الاستيسيته توده سنگ تكيه‌گاه، توليد شده و عمليات بهينه‌سازي بر روي آنها انجام مي‌گيرد و شكل بهينه نمونه‌هاي سدهاي بتني قوسي به دست مي‌آيند. با بررسي شكل سدهاي موجود در شرايط مختلف ساختگاه، قوانين حاكم بر تغييرات شكل سدهاي بهينه نسبت به تغييرات مشخصات ساختگاه، استخراج مي‌شود. از مهم‌ترين نتايج حاصل از اين پژوهش، مشاهده روند افزايشي متغيرهاي طراحي ضخامت در طره مركزي و در تكيه‌گاهها نسبت به افزايش مدول پي است. اين قوانين مي‌توانند به عنوان رهنمودهايي در هنگام طراحي شكل سدها استفاده شود.

One of the most important issues in arch dam design, is optimum shape design of the dam body in such a way that both safety and economical constraints could be satisfied. The aim of this research is the introduction of some patterns for optimum arch dam shape in seismic zones and the identification of the optimum shape trends in proportion to physical and geometrical parameters of each specific site. Method of research includes parametric and statistical calculations on several arch dam sites samples. Thus optimization procedures are performed on dams with different heights, canyon widths, canyon shape types (V-shape or U-shape), and foundation moduli of deformation. Studying the resulting optimized arch dams shapes, certain trends of design variables is deduced in order to achieve optimum shape of the dam body when site specification changes. These trends are showed in graph forms. Resulting rules can be used as arch dam design guidline. One of the most important results of this study is the increasing trend in the thickness design variables in the central cantilever and abutments with the increase of the foundation modulus of elasticity. These rules can be used as guidelines for dam shape design. One of the most important issues in arch dam design, is optimum shape design of the dam body in such a way that both safety and economical constraints could be satisfied. The aim of this research is the introduction of some patterns for optimum arch dam shape in seismic zones and the identification of the optimum shape trends in proportion to physical and geometrical parameters of each specific site. Method of research includes parametric and statistical calculations on several arch dam sites samples. Thus optimization procedures are performed on dams with different heights, canyon widths, canyon shape types (V-shape or U-shape), and foundation moduli of deformation. Studying the resulting optimized arch dams shapes, certain trends of design variables is deduced in order to achieve optimum shape of the dam body when site specification changes. These trends are showed in graph forms. Resulting rules can be used as arch dam design guidline. One of the most important results of this study is the increasing trend in the thickness design variables in the central cantilever and abutments with the increase of the foundation modulus of elasticity. These rules can be used as guidelines for dam shape design. One of the most important issues in arch dam design, is optimum shape design of the dam body in such a way that both safety and economical constraints could be satisfied. The aim of this research is the introduction of some patterns for optimum arch dam shape in seismic zones and the identification of the optimum shape trends in proportion to physical and geometrical parameters of each specific site.