Liquefaction, ground deformation and their related damage to structures

This paper introduces an outline of liquefaction, its induced ground deformation and damage to lifeline facilities and foundations of buildings and bridge piles during the 1995 Hyogoken-nambu (Kobe) earthquake. Characteristics of ground displacement andstrain measured by aerial survey are described. Some typical examples of large ground displacements are presented and a casual relationship of damage to buried pipes and foundation piles with the ground displacements is investigated. In addition, the present paper introduces several examples of foundations proved to have resited against the liquefaction and its induced ground displacements during the earthquake. (AU)

Relationship between geomorphological land classification and soil amplification ratio based on JMA strong motion records

The relarionship between the soil amplification ratio and ground conditions was examined using strong motion records measured at 77 Japan Meteorological Agency (JMA) stations over a period of more than 8 years. The amplification ratios for the instrumental JMA intensity, as well as for the peak ground acceleration and velocity, were obtained from the station coefficients of the attenuation relationships. A combined use of geomorphological land classification and subsurface geology was found to yield the best estimate of the amplification ratio. This result suggests that the Digital National Land Information may be conveniently used for the estimation of strong motion distribution over large areas in Japan.(AU)

Ground displacement and strain caused by soil liquefaction during the 1995 Hyogoken-Nambu earthquake

This paper introduces an ouline of liquefaction-induced ground displacements during the 1995 Hyogoken-nambu earthquake, wich were measured by an aerial survey, and describes the characteristics of the ground displacements. It also outlines the ground strain caused by the liquefaction, which were analyzed from the measured ground displacement, and discusses a relationship between the magnitude of the ground strain and the damage rate of buried pipes. (AU)

Effects of liquefaction - induced large ground displacement on earthquake resistance of foundations during the Hyogoken - Nambu earthquake

This paper performances of foundations under a condition of liquefaction - induced ground displacement and investigates the effects of the ground displacements on the earthquake resistance of the foundations. It also introduces some examples of undamaged foundations even when the surrounding ground largely moved horizontally. (AU)

Liquefaction - induced ground deformation and its caused damage during the 1995 Hyogoken-Nanbu earthquake

Liquefaction-induced ground deformations in reclaimed lands generated by the 1995 Hanshin-Awaji earthquake are described. Some typical examples of large ground displacements which were measured by aerial survey are introduced and their caused damage to buried pipes, foundation piles and storage tanks are presented. Characteristics of ground displacements and strains in the filled areas are investigated.(AU)

Ground deformations and their effects on structures in midorigaoka district, Kushiro City, during the Kushiro-Oki earthquake od January 15, 1993

This paper presents yhe ground failuress observed at Midorigaoka during the Kushiro-oki earthquake and examines the relationships within ground deformation patterns, subsurface ground conditions, landform changes, and the perfomance of wood houses and underground utility lines.(AU)

Liquefaction history, 416 - 1990, in Japan

Liquefaction has been known to recur at the same site during successive earthquakes. Maps showing locations of past liquefaction occurrences are very useful to delineate and characterize areas of liquefaction susceptibility for future earthquakes. This paper summarizes historical occurrences of liquefaction during the period 416-1990 in Japan. Maps showing distribution of liquefied sites in these earthquakes are compiled based on documentary study, post-earthquake reconnaissance investigations, and interviews to local residents. Totally 123 earthquakes which induced liquefaction are listed. More than 100 locations where liquefaction recurred at the same site during succesive earthquakes are presented. Furthermore, seismic intensities which generated the liquefaction effects are examined and relationships between the distance from epicenter and energy source to the farthest liquefied sites and an earthquake magnitude are studied, respectively based on data from the earthquakes.(AU)

Liquefaction - induced ground deformations during the 1923 Kanto earthquake

Three case histories of liquefaction-induced ground displacement generated by the 1923 Kanto earthquake are reviewed herein. By re-examining already published damage reports and interviewing local residents, sites of liquefaction-induced ground failure and displacement were identified. The general character and regional extent of these displacement patterns and failures are described, and geomorphological and geotecnical data from displacement sites are examined. Liquefield layers were evaluated by comparing the color and grain size of the vented materials and soil samples taken from bore holes made at each displacement site, and on analytical methods for assessing susceptibility to liquefaction as employed in the Japanese Highway Bridge Code.