مطالعه آزمایشگاهی دیوارهای خشتی تقویت شده به روش کاشت نزدیک سطح تحت بار جانبی چرخه‌ای

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجو/ دانشکده عمران/دانشگاه یزد

2 عضو هیئت علمی / دانشگاه یزد

چکیده

در سازه‌های بنایی، دیوارهای باربر نقشی مهم و اساسی در عملکرد لرزه‌ای کلی و حفظ یکپارچگی سازه دارند. بنابراین استراتژی های مقاوم ٌ سازی این نوع سازه‌ها عموما شامل مقاوم سازی دیوارها می‌شود. از روش های تقویت دیوارهای بنایی، روش کاشت در نزدیک سطح با استفاده از مصالح فولادی یا کامپوزیتی است. هرچند سازه‌های خشتی نیز جزئی از سازه های بنایی محسوب می‌شوند، ولی تحقیقات کمتری در مورد مقاوم سازی این سازه ها نسبت به سایر انواع سازه‌های بنایی صورت گرفته است. در تحقیق حاضر مقاوم سازی لرزه ای دیوارهای خشتی در برابر بارهای جانبی با استفاده از روش کاشت نزدیک سطح میلگردهای فولادی مورد ارزیابی آزمایشگاهی قرار گرفته است. نمونه های آزمایشگاهی شامل چهار نمونه دیوار خشتی با مقیاس یک سوم به طول یک متر، ارتفاع 800 میلی‌متر و ضخامت 200 میلی‌متر بودند. میلگردهای تقویت یه روش کاشت نزدیک سطح به صورت شبکه متعامد در هر دو طرف نمونه‌های دیوار نصب شدند. نمونه‌ها همزمان تحت تنش فشاری محوری ثابت 0/1 مگاپاسکال و بارگذاری جانبی درون صفحه ای چرخه‌ای افزایش یابنده با کنترل تغییر مکان قرار گرفتند. بر اساس نتایج آزمایش ها، روش کاشت نزدیک سطح میلگرد فولادی با قالب انتهایی تاثیر قابل توجهی در بهبود مقاومت جانبی، سختی جانبی درون صفحه ای و شکل‌پذیری نمونه‌های دیوار خشتی داشت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental investigation on the NSM retrofitted adobe walls under cyclic lateral loading

نویسندگان [English]

  • Hosein Mirabi Banadaki 1
  • reza morshed 2
1 Civil Eng. Dept.,Yazd University
2 Yazd University / member of Scientific Board
چکیده [English]

In masonry structures, load bearing walls play a crucial role in the overall seismic performance and structural integrity. Thus, their retrofitting strategies typically involve retrofitting of their walls. One of the retrofitting technique can be using steel or composite materials in the form of near-surface-mounted (NSM) reinforcement. Despite being considered as masonry structures, there have been fewer investigations on seismic retrofitting of the adobe structures. In the current study, the efficiency of NSM steel rebars in improving the seismic performance of adobe wall is investigated through experimental investigations. The test specimens were comprised of four scaled-down (1/3) adobe walls measuring 1000 mm in length, 800 mm in height, and 200 in thickness. Retrofitting bars, in the form of two perpendicular NSM meshes, were applied on both sides of the walls. The specimens were tested under an incremental in-plane cyclic loading reversals applied simultaneously with a constant axial pre-compression of 0.1 MPa. Based on the obtained experimental results, NSM technique accompanied with the proposed anchorage system had a considerable effect in improving the lateral strength, lateral in-plane stiffness, and ductility of adobe wall specimens.

کلیدواژه‌ها [English]

  • Adobe wall
  • Cyclic loading
  • NSM technique
  • Retrofitting
  • Ductility
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