Centrifugal Model Tests on Settlement Controlling of Piled Embankment in High Speed Railway

The settlement after construction controlling of subgrade is a crucial issue on designing of high speed railway. Based on the experimental study at home and abroad, the centrifuge model test is used to imitate piled embankment in different pile spacing to research and analyze the settlement controlling ability of piled embankment in collapsible loess ground in high speed railway. Then the relationship between pile, lime-soil cushion, soil between piles controlling the settlement are concluded by analyzing the test data. The research results show that untreated ground which can not meet the request on settlement after construction in ballasted track in high speed railway need be reinforced. The total settlement, settlement after construction and settlement ratio of piled embankment get larger with the extending of pile spacing. The settlement of soil is faster and more increasing than settlement of pile, and pile-soil load share ratio get lower and negative skin friction of pile get more increasing.