Discharge Path Model in Model Test of Lightning Strokes to Tall Mast

The discharge path model is proposed on the basis of the observations on the discharge path in the model test. The model gives satisfactory explanations of the striking probability to the model mast. The model yields the deterministic striking parameter which is independent of the wave shape of the applied impulses but depends only on its polarity for a given set of the mast height and gap spacing. The discharge path model is applied to the estimation of the frequency of the natural lightning strokes to the tall structures and to the estimation of their shielding effects.