نوع مقاله : یادداشت فنی

نویسندگان

• سلیم عزیزی
• فرزین سلماسی
• اکرم عباسپور
• هادی ارونقی

چکیده

برای ایمنی سد در برابر آبشستگی زیر پی و نیروی بالا برنده می‌توان از روش‌هایی مانند تعبیه دیواره سپری در بالادست و پایین‌دست سازه،‏ افزایش طول کف‌بند بتنی سازه و یا احداث سوراخ‌آب در حوضچه آرامش استفاده کرد. در این پژوهش که بر روی سد انحرافی یوسف کند مهاباد انجام شده،‏ با شبیه‌سازی سد در نرم‌افزارSeep/W تأثیر تعداد سوراخ‌ها،‏ موقعیت سوراخ آن‌ها در طول حوضچه آرامش و همچنین طول پرده‌های آب‌بند بر روی زیرفشار و گرادیان هیدرولیکی خروجی در نقاط کلیدی پی زیر سد انحرافی بررسی و پایداری کلی سد بررسی شده است. در بررسی انجام شده دیده شد که احداث دیوار آب‌بند ابتدایی به عمق 8 متر موجب کاهش 63 درصد از نیروی بالا برنده و کاهش 79 درصد از گرادیان خروجی نسبت به حالت بدون آب‌بند می‌شود. همچنین احداث سوراخ‌آب در حوضچه آرامش سبب کاهش 8 درصد از نیروی بالا برنده و کاهش 74 درصد از گرادیان خروجی نسبت به حالت بدون سوراخ‌آب می‌شود.

کلیدواژه‌ها

• گرادیان هیدرولیکی خروجی
• دیوار آب‌بند
• زیرفشار
• سوراخ‌آب
• سد انحرافی

عنوان مقاله [English]

Effect of weep hole on decreasing of uplift pressure in Yusef Kand Mahabad diversion dam

نویسندگان [English]

• Salim Azizi
• Farzin Salmasi
• Akram Abaspour
• Hadi Oronaghi

چکیده [English]

In order to have an economic design to reduce uplift pressure in weighted concrete dams, so many methods have been proposed that the most important include: adding horizontal apron, cutoffs in upstream and downstream of the dam and weep hole installation in downstream or proper place between the two cutoffs. These implementations also reduce the exit gradient. The effects of these parameters are the main subject of this study. This study focuses on Yusef Kand Mahabad diversion dam, by study on the dam and its simulation in Seep/W software, effect of number of weep hole on uplift pressure, proper location of weep holes on stilling basin and also the length of the dam cutoffs. Simulation was studied on uplift pressure and exit hydraulic gradient in key points of diversion dam and the overall stability of the dam. In this study, it was observed that creating primary upstream cutoff with 8 m length decreases uplifting force about 63% and decrease exit gradient 79% than the case without cutoff. Creating a weep hole in the stilling basin decreases uplifting force 8% and decrease exit gradient 74% than the case without weep hole. Results demonstrate that suitable location of weep holes can reduce uplift pressure and so the diversion dam design can be safe and economical.In order to have an economic design to reduce uplift pressure in weighted concrete dams, so many methods have been proposed that the most important include: adding horizontal apron, cutoffs in upstream and downstream of the dam and weep hole installation in downstream or proper place between the two cutoffs. These implementations also reduce the exit gradient. The effects of these parameters are the main subject of this study. This study focuses on Yusef Kand Mahabad diversion dam, by study on the dam and its simulation in Seep/W software, effect of number of weep hole on uplift pressure, proper location of weep holes on stilling basin and also the length of the dam cutoffs. Simulation was studied on uplift pressure and exit hydraulic gradient in key points of diversion dam and the overall stability of the dam. In this study, it was observed that creating primary upstream cutoff with 8 m length decreases uplifting force about 63% and decrease exit gradient 79% than the case without cutoff. Creating a weep hole in the stilling basin decreases uplifting force 8% and decrease exit gradient 74% than the case without weep hole. Results demonstrate that suitable location of weep holes can reduce uplift pressure and so the diversion dam design can be safe and economical.In order to have an economic design to reduce uplift pressure in weighted concrete dams, so many methods have been proposed that the most important include: adding horizontal apron, cutoffs in upstream and downstream of the dam and weep hole installation in downstream or proper place between the two cutoffs. These implementations also reduce the exit gradient. The effects of these parameters are the main subject of this study. This study focuses on Yusef Kand Mahabad diversion dam, by study on the dam and its simulation in Seep/W software, effect of number of weep hole on uplift pressure, proper location of weep holes on stilling basin and also the length of the dam cutoffs. Simulation was studied on uplift pressure and exit hydraulic gradient in key points of diversion dam and the overall stability of the dam. In this study, it was observed that creating primary upstream cutoff with 8 m length decreases uplifting force about 63% and decrease exit gradient 79% than the case without cutoff. Creating a weep hole in the stilling basin decreases uplifting force 8% and decrease exit gradient 74% than the case without weep hole. Results demonstrate that suitable location of weep holes can reduce uplift pressure and so the diversion dam design can be safe and economical.In order to have an economic design to reduce uplift pressure in weighted concrete dams, so many methods have been proposed that the most important include: adding horizontal apron, cutoffs in upstream and downstream of the dam and weep hole installation in downstream or proper place between the two cutoffs. These implementations also reduce the exit gradient. The effects of these parameters are the main subject of this study. This study focuses on Yusef Kand Mahabad diversion dam, by study on the dam and its simulation in Seep/W software, effect of number of weep hole on uplift pressure, proper location of weep holes on stilling basin and also the length of the dam cutoffs. Simulation was studied on uplift pressure and exit hydraulic gradient in key points of diversion dam and the overall stability of the dam. In this study, it was observed that creating primary upstream cutoff with 8 m length decreases uplifting force about 63% and decrease exit gradient 79% than the case without cutoff. Creating a weep hole in the stilling basin decreases uplifting force 8% and decrease exit gradient 74% than the case without weep hole. Results demonstrate that suitable location of weep holes can reduce uplift pressure and so the diversion dam design can be safe and economical.

کلیدواژه‌ها [English]

• Weep hole
• Diversion dam
• Uplift pressure
• Exit hydraulic gradient
• Cutoff wall