S - Kam Ng PhD Dissertation Final.pdf - Digital Repository of CCEE ...

122A literature review by the writers concluded that published information on pile setuplacks detailed dynamic and static field test data as a function of time for both smalldisplacementpiles (i.e., H-piles and open-ended pipe piles) and large-displacement piles(closed-end pipe piles and precast concrete piles). In addition, quality setup data on smalldisplacementpiles is relatively scarce according to the published data of pile setup reportedby Long et al. (1999), Titi and Wathugala (1999), and Komurka et al. (2003). Furthermore,despite the fact that pile setup is influenced by properties of soil surrounding the pile andpore water pressure, the necessary data to quantitatively describe the relationship betweenpile setup and surrounding soil properties and dissipation of pore water pressure is notavailable. This raises a question if the pile setup of small-displacement driven piles issignificant. If this is significant, then its dependency on surrounding soil properties and porewater pressure and its incorporation into the LRFD approach need to be studied. Given that arecent survey of more than 30 State Departments of Transportation (DOTs) conducted byAbdelSalam et al. (2010) revealed that steel H-pile is the most common foundation type usedfor bridges in the United States, the setup investigation reported herein focuses on steel H-pile.3.3. BackgroundOne of the first observations of setup for steel H-piles was reported by Yang (1956)on 58 m long HP 360 × 174 piles embedded in silty clay layers at the Tappen Zee Bridge sitein New York. In this case, the pile resistance based on hammer driving resistancemeasurements increased from 1 blow/0.3m to 8 blows/0.3m after 2 days from the EOD.Similar soil setup observations for various steel H-piles embedded in cohesive soils (seeFigure 3.1) have been reported by Huang (1988) and Lukas & Bushell (1989), and morerecently by Long et al. (2002) and Fellenius (2002). Figure 3.1 summarize the setup found inthe literature for steel H-piles in terms of a resistance ratio defined as the total pile resistanceat any time after the EOD (R t ) divided by the reference total pile resistance at the EOD(R EOD ). The total pile resistances (R t ) were determined either using the measured responsefrom a static load test or based on Pile Driving Analyzer (PDA) measurements in conjunction