| 摘要 |
<p>PROBLEM TO BE SOLVED: To approximately estimate the attenuation of strong earthquake motion with respect to distance with small error, by approximately indicating the attenuation concerning spatial diffusion of body wave with a specific equation using the depth of the focus, a distance from the focus to an arbitrary point on the ground surface, and amplitude attenuation of body wave from the focus to the arbitrary point. SOLUTION: Let the depth of focus from the ground surface H, a distance from the focus to arbitrary point on the ground R and distance attenuation of amplitude of body wave from the focus to the arbitrary point D, and the attenuation concerning spatial diffusion of amplitude of the body wave is expressed approximately by D=H<1/2> R<3/2> . This approximation equation gives a large effect in calculating input earthquake motion necessary for constructing various important structures.</p> |
