Skirt-anchor-bolt design

This section outlines the wind design procedures for both of these standards. Wind design is used to determine the forces and moments at each elevation to check if the calculated shell thicknesses are adequate. The overturning moment at tlie base is used to determine all of the anchorage and support details. These details include the number and size of anchor bolts, thickness of skirt, size of legs, and thickness of base plates. 

Dimension a should be kept to a minimum to reduce induced stresses in the skirt, This will provide a more economical design for base plate, chairs, and anchor bolts. 

N = Number of support points Nb = Number of anchor bolts P = Design pressure, PSIG Pt> Pc = Load at top of skirt, tension or compression, Lbs/in... 

Once the thickness of the skirt, t, is determined, the next task is to design the anchor bolts. If the total number of anchor bolts are N, then the load on a single bolt, P, from the consideration of bending about a neutral axis is given by... 

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