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A large rocket is installed on a launching table. The total height of the rocket is 100m and average diameter is 8m. To secure the rocket on the launching table it is bolted to the table with 34 bolts. These bolts serve two purposes: 1. Hold the rocket down and resist side wind of up to 70 m/sec. 2. Release the rocket when the total thrust of the engine reaches its maximum value of 1 20MN, which is 1.5 times the weight of the rocket W = 80 MN. To achieve this, the bolts are made from titanium alloy with the following mechanical properties: Young's modulus E =116 GPa; Shear modulus G = 44 GPa; Poisson's ratio = 0.32; Tensile strength ou = 1170MPa; 0.2% yield strength 002 = 1100 MPa. Bolts have a notch on a shank to weaken them and facilitate rupture (see figure below). When rocket engines develop full thrust, bolts rupture at the notch and release the rocket. Bolts are evenly distributed along the circle of diameter D equal to the diameter of the rocket and hold together two flanges - one attached to the rocket, and another is built in the concrete launching table. The total thickness of the flanges is L = 100mm. Flanges are made from stainless steel with the following mechanical properties: -Tensile strength ou = 760 MPa: -Yield strength oy = 415 MPa: -Young's modulus E = 2.15-1011 Pa; -Poisson's ratio = 0.3. It is necessary to design bolts that will rupture and release the rocket when rocket engines develop full thrust, and will resist the side wind of up to 70 m/sec. Follow the procedure outlined below, make necessary assumptions and calculations. H W h = H/2 T D = 8,100.00 D = 8,000.00 Rocket on a launching table Flange section with a bolt Discuss what methods are used to secure a large rocket on a launching table Assess the force that will rupture the bolts during the blastoff Calculate the force per bolt Calculate the cross-sectional area of the bolt shank at the notch and the diameter at the bottom of the notch. Ignore stress concentration at the notch. Select the bolt size of the metric series and make sure that the minor thread diameter d1 is at least 20% greater than the notch diameter.