Energy measurement in the standard penetration test

The standard penetration test, SPT is used in subsurface investigation for routine foundation designs. The routine foundation designs are accomplished by the use of SPT 'N' value. A field measurement system and procedure which measures the energy delivered by a drill rig system were developed and successfully used to study the factors which affect delivered energy. The energy delivered by certain drill rig systems used in engineering practice is indicated. Also, the transmission characteristics of certain hammer/anvil systems are examined. Guidance on the need to measure the actual fall height of the hammer during the standard penetration test is provided.