抄録
The results of investigation of soil liquefaction and related damage to several structures during the Haicheng earthquake of 1975 (M=7.3) and the Tangshan earthquake of 1976 (M=7.8) in China are described. Extensive soil liquefaction occurred during these two earthquakes especially in the sandy deposits of the Holocene period and in the abandoned old river beds. Numerous bridges, buildings, embankments and others were seriously damaged due to soil liquefaction. The maximum ground acceleration at liquefied sites were estmated 100 gals or more. The maximum epicentral distance Rmax (km) of liquefied sites for these two earthquakes were well represented by the equation ; log10Rmax=0.77M-3.6 in which M is the earthquake magnitude. This equation has been proposed for fourty four Japanese earthquakes in the past. Some discussions were made on the method of evaluation of liquefaction potential using the standard penetration test N-values or the static cone penetration test qc-values.
