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Piles and Pile Driving Jackson Tukuafu Brandon Smith • //www.youtube.com/watch? v=aNfDco8eXA8 • http://www.youtube.com/watch? v=o_kqh0aGEwo Safety First Pile Driving Terminology Anchor Pile: pile that is connected to a structure Butt of pile: the fat end of the pile Cushion: spreads out impact of the hammer Cutoff: height you cut your pile after its been driven Downdrag: condition that adds load to the installed pile Driving cap/ helmet: protects top of pile while being driven Embedment: how much is in the ground Overdriving: too much driving damages your piles Penetration: how far it goes in each time you hit it Pile bent: more than one pile driven in a cluster Pile-driving shoe: Metal shoe on bottom end to make it go in better Soldier pile: holds up an excavation Tension pile: holds structure down from being pulled out Pile Hammers Types of Hammers • Drop Hammers • Single-acting steam or compressed air • Double-acting steam or compressed air • Differential-acting steam or compressed air • Diesel • Hydraulic-impact and drivers • Vibratory drivers Hammer selection considerations: 1. Number of piles 2. Character of the soil 3. Location of the project 4. Topography of site 5. Equipment available 6. Pile driving on land or water Pile Hammers • Drop Hammers – Only used in remote areas with less piles – Time of completion is not important – Productivity • 4-8 blows/min – Not suitable for concrete piles Pile Hammers • Double-Acting Hammers – “ram” is driven by compressed air to steam both when rising and when falling – 95-300 blows/min. – Lighter ram and high Pile Hammers*** • Single-Acting Hammers – 40-60 blows/min – Sizes vary 7000- 1,800,000 ft- lb/blow – “Ram” is lifted by steam or compressed air and then dropped Pile Hammers*** • Differential-Acting – Uses the advantages of a single- and double-acting hammers Pile Hammers • Diesel Hammers – Open end • 40-55 blows/min. – Close end • 75-85 blows/min. – Used in cohesive or very dense soils