This study presented centrifuge modeling for seepage and deformation of slopes and embankments subject to postshaking rainfall and seepage. First series of centrifuge experiments on small-scale slope models under post-shaking rainfall were performed. Shaking-induced cracks on the slope were near its shoulder and the existence of cracks greatly affected slope behavior during the following rainfall, and the rainfall-induced landslide was affected by both rainfall intensity and previous-shaking intensity. Heavy rainfall greatly accelerated the failure of the slope with shakinginduced cracks, resulting in a rapid and massive landslide. Second series of centrifuge experiments on river levee models under post-shaking seepage were performed. Two types of embankment models with different internal structures were set up to examine the effect of internal structure on seismic and seepage behavior. After shaking the embankment model, seepage experiments were carried out by giving a water level. The seismic deformation of embankment during shaking showed the similar tendency as observed in the past damaged cases. The difference in the internal structure caused different behavior in the seismic deformation during shaking and seepage performance after shaking. .

This paper summarises findings of a series of 1-g physical model tests conducted on small-diameter steel pipes buried in compacted partially-saturated, saturated and dry sandy backfill materials of similar grain size distribution and dry density. The main aim of these tests was to measure under carefully controlled laboratory conditions the force that will develop on a rigid pipe buried in different backfills as result of relative vertical upwards or lateral permanent deformation of its surrounding soil, ensuing from rupture of a normal or a strike-slip seismic fault. The presentation focuses on i) exploring how sensitive this reaction force is to matric soil suction, which will develop even in sandy partially-saturated compacted backfills, and ii) documenting the mechanisms through which suction increases the resistance offered by the backfill to relative pipe movements. Analysis of comprehensive data collected during the tests revealed that the failure mechanisms that are formed in partially-saturated backfills during pipe movement features notable differences to the mechanisms that are formed in dry or saturated backfills, where the reaction force on the pipe is grossly lower. Findings of this study have important implications for the analysis of buried steel pipes subjected to fault rupture, even for pipes which backfill has relatively low suction potential.