Pile Load Test of Post-grouting Bored Pile at Beijing Capital International Airport

Abstract

Bottom slime and shaft mudcake are two principal deteriorative factors affecting the mobilization of bearing capacity of slurry bored piles. As an effective later improvement technology, post-grouting can significantly improve bored pile bearing capacity. Based on static load test results of Beijing capital international airport project, vertical bearing properties of post-grouted bored pile have been studied. The analyses reveal that: with pile-toe and pile-shaft post-grouting, the interface between pile and surrounding soil was strengthened and the relative sliding displacement in between was reduced, end resistance of pile was enhanced and could be mobilized at earlier stage with smaller sliding displacement. As a result, the performance of bored pile was improved with increased bearing capacity and reduced settlement.