نوع مقاله : یادداشت فنی
نویسندگان
1 گروه مهندسی عمران، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران
2 گروه مهندسی مکانیک، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران.
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The arch is a fundamental and aesthetic component of Iranian architecture, integral to the stability and beauty of buildings since ancient times. Modern domes often cover large spaces without internal supports, with their shape playing a vital role in handling gravitational and lateral loads. Domes can also be subjected to shock loads from events like earthquakes, impacting their structural integrity. This study explores the mechanical and impact properties of concrete domes reinforced with steel fibers. While most previous research has focused on the impact effects on concrete slabs, this study shifts the focus to concrete domes. It examines how different percentages of steel fibers (0, 0.5, 1, and 1.5) and varying dome thicknesses (50, 75, and 100 mm) affect impact resistance. Steel fibers enhance the compressive strength, crack control, and overall durability of concrete. The research involved compressive, tensile, and bending strength tests, as well as an impact test using a 10 kg steel weight dropped from a height of 3260 mm. Abaqus software was employed to compare numerical simulations with laboratory results, using models from Popovich for compression and Shima for tensile behavior. The impact test assessed three key parameters: the number of impacts to create the first effective crack, the number of impacts until dome failure, and the energy absorbed by the dome. Findings revealed that steel fibers significantly improve the impact resistance and energy absorption of concrete domes. A 100 mm thick dome with 0.5% steel fibers absorbed 33% more energy than a 50 mm dome without fibers. When the fiber content was increased to 1% and 1.5%, energy absorption rose by 60% and 78%, respectively. Similarly, increasing the dome thickness to 75 mm with 0.5% fibers resulted in a 67% increase in energy absorption compared to the control sample without fibers. For domes with 1% and 1.5% fibers, energy absorption increased by 80% and 82%, respectively. The study concluded that both the addition of steel fibers and increased dome thickness substantially enhance the impact resistance of concrete domes. The most significant improvements were observed in domes with a 100 mm thickness, where the number of impacts required to cause damage increased by 68% and 64% compared to 50 mm and 75 mm thick domes with 1.5% fiber content. This highlights the crucial role of both fiber reinforcement and thickness in improving dome resilience against impacts.
کلیدواژهها [English]
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