Isolation of DDC Impact to Sheet Pile Walls by Open Trenches

This paper investigates the effectiveness of open trenches in reducing the deflections of sheet pile walls during deep dynamic compaction (DDC). This investigation included a series of comprehensive parametric studies using a two-dimensional (2D) finite-element (FE) method. Prior to investigation, a new dynamic approach based on the time history of tamper penetration depth was developed to simulate DDC impact, and its reliability and accuracy were verified by field measurements. Then, three open trenches with different cross-section shapes were examined. The dimensional effects of the trenches on reducing wall deflections were analyzed and discussed, and their reduction efficiencies were compared. For the investigated shallow open trenches, increasing trench depth or width can efficiently improve their isolation effects on reducing wall deflections. The cross-section shapes of open trenches do not impose apparent influences. DOI: 10.1061/(ASCE)GT.1943-5606.0000544. (C) 2012 American Society of Civil Engineers.