Mechanical-Impedance Characteristics at Ends of a Rockdrill Rod

Although lacking the mechanical precision refinements hitherto reported, a conventional rockdrill hammer and drill rod comprise the experimental elements in derivation of mechanical impedance from transient waveforms. With allowance for nonlinearities and other limitations, it is demonstrated that new information is provided on hammer vibration and rock fracture at impact. Also, a single cylinder replaces the two cylinders previously required for this method of impedance determination.