كليدواژه :
انبار مواد منفجره , بارگذاري انفجار , ديوار برشي , سپرمحافظ بتني , نرم‌افزار ABAQUS
چكيده فارسي :
حملات تروريستي با آسيب رساندن به سازه ها و زيرساخت هاي يك كشور ميتواند صدمات مالي و جاني زيادي را نيز به بار آورد؛ بنابراين توجه به موضوع پدافند غيرعامل در ساخت سازه ها و همچنين طراحي و كنترل اين سازه ها بايد مدنظر قرار گيرد. يكي از مهم‌ترين زيرساخت هاي كشور معادن هستند. در معادن، حساسترين و آسيبپذيرترين محل در حملات تروريستي انبارهاي نگهداري مواد منفجره و چاشني ها و فتيله‌هاي انفجاري هستند. در اين پژوهش انبار نگهداري چاشني هاي الكتريكي با ابعاد 5/6 در 5/3 متر ابتدا در ETABS طراحي و سپس براي بررسي رفتار و ميزان مقابله اين ديوار در برابر بار انفجاري، از برنامه اجزاي محدود ABAQUS استفاده شد. ديوار برشي U شكل، با طول و ارتفاع سه متري انتخاب گرديد. ديوار برشي در چهار حالت: بدون سپر و همراه با سپر محافظ 8، 10 و 15 سانتي‌متري، براي مقابله با بارهاي انفجاري بررسي شد. بارهاي انفجاري در سه فاصله 10، 50 و 100 سانتي‌متري از مركز سپر قرار داده شد. مشخص گرديد كه وجود سپر محافظ بتني ميتواند به شدت ميزان جابجايي ديوار برشي را تا 4/97 درصد، ميزان تنش ديوار برشي را تا 4/56 درصد و ميزان تنش پاي ستون را تا 7/36 درصد كاهش دهد و از ديوار در برابر بارهاي انفجاري محافظت نمايد. نتيجه بررسي نشان داد تركيب ديوار برشي بتني به همراه سپر محافظ، سازه مناسبي براي نگهداري مواد منفجره و چاشنيهاي انفجاري معادن خواهد بود.
چكيده لاتين :
Summary
Terrorist attacks could cause serious destruction and death by damaging to buildings and infrastructures. One of the most vulnerable mine structures are storages containing explosives, detonator caps and Detonation fuse. In this study a 6.5 x 2.5 storage of electrical caps is designed by ETABS firstly. Then its wall is modeled in finite element commercial software ABAQUS in order to investigate its behavior and resistance under blast loads. The U-shaped shear wall type with dimensions of 3x3 meter is chosen for this wall, and the wall is considered in 4 conditions: with 8, 10 and 15 cm protective shield and without protective shield. Blast loads are positioned in 10, 50 and 100cm distance of center of the shield. The results show that in the existence of the shear wall, displacements of the shear wall, shear stress of the wall and stress at the base of the column decreases up to 97.4%, 56.4% and 36.7% respectively. It’s concluded that reinforcement of shear walls with protective shields provides sturdy structures in order to store explosives and detonator caps in mines.
Introduction
If an explosion takes place outside of these detonator caps and detonation fuses, the of the blast wave effect could cause a blast at explosives inside the storage and lead to a great damage. Hence, it’s important to study these effects on this kind of structures. In this study, a 3.5x6.5 storage of electrical cap, whose walls are designed as U-type shear walls protected by concrete shield. In order to investigation behavior of the wall and the effectiveness of the shield against blast loads, a wall with dimensions of 3x3 is modeled in ABAQUS under 4 distinct conditions: with various 8, 10 and 15 cm shield and without shield.
Methodology and Approaches
To design the walls, the software ETABS is used, and finite element commercial software ABAQUS, which has great ability to solve explicit dynamic problems, is employed to simulate the behavior of walls and shields under blast loads.
Results and Conclusions
By protecting the wall against blast loads, Concrete shield was able to reduce the displacement of the wall, stress of the wall and stress at the base of the column up to 97.4%, 56.4 and 36.7 respectively. Besides, it keeps explosives and detonator caps inside the storage safe by degrading the energy of the outside blast wave.
