Typically, impact hammer selection must consider drivability, testing requirements (assuming the same hammer is used for high strain dynamic testing), and the potential for pile damage, especially where piles are installed into dense or hard strata. Criteria for minimum, preferred and maximum hammer size required for pile installation, testing, and damage mitigation will be reviewed and summarized. Maximum driving stresses and the effect of pile cross section relative dimensions will be discussed. The paper will provide suggested guidelines for a preliminary screening tool for selecting an impact hammer to safely install and test steel pipe and H-piles, and illustrate this through a brief case study. A companion paper will examine in depth a recent case history where an H-pile was damaged during installation and testing, make use of the screening tool and advanced pile driving simulation software to show how the pile damage could have been predicted.
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