Foundations for Guyed Towers

It was shown by equation (11-1) that the total soil loading, to be considered in the design of tower foundations, is the sum of Si, the dead load, and S2, the load caused by the overturning or wind moment. There is no overturning moment on guyed towers however, the wind pressure does have an important effect on the foundation, as the soil is required to resist the vertical component of the pull on the guy wires. 

For guyed towers, therefore, equation (11-1) must be revised as follows  

Foundation bolts for guyed towers are required to resist the shearing action of the wind pressure at the base of the tower. It is obvious that ample allowance should be made in the size of the bolts to provide for the initial tension caused by tightening the nuts and for corrosion. 

The shear at the base of the tower, which must be resisted by the bolts, is equal to the horizontal reaction to the wind pressure at that point. This is equal to the difference between the total wind pressure and the reaction at the collar and can be expressed as follows  

Rjj = horizontal wind reaction, or shear, at the base of the tower, lbs. 

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