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Underground Pipe Damages and Ground Characteristics.
Shinozuka, M.; Kawakami, H.
National Science Foundation, Washington, DC. Applied Science and Research Applications., June 1977, 17 p.
A method is proposed under the quasi-two-dimensional free field conditions to evaluate the elastic surface strains arising from spatial variability of the soil property (ground predominant frequency) of a surface layer subjected to shear waves incident vertically from below through a semi-infinite firm ground. The variability is described in terms of a random function of the space variable characterized by mean value, variance and correlation distance. Applying the method, the strains are evaluated for the metropolitan Tokyo area on the basis of the local soil conditions, and a reasonable correlation has been established between such strains and the damage statistics collected on the underground water supply pipeline under the 1923 Kanto Earthquake. This investigation is currently being extended so that the free field strains are evaluated not at the free ground surface but at a usual depth for underground water supply pipelines.
Ground motion; Earthquake engineering; Pipelines; Earthquakes; Water pipes; Tokyo (Japan); Soil dynamics; Earth movements; Shear strain; Subsurface structures; Japan; Seismic waves