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Impacts of Mechanical Equipment at Benson Brothers Quany on Neazby Rock <br />Velocity of Partite Motion or Air Overpressure Plotted <br />with respect to time <br />a I 1 CYrCLE <br />a <br />J <br />m <br />a <br />nad~gmund <br />Noise <br />`o <br />a Peak <br />Amplitude <br />Event Duration <br />TIME <br />~- <br />Figure 3: Idealized Vibration or Air Overpressure Time-Intensity History Plot <br />Particle displacement (in) =Particle velocity / (2 n f) Equation 1.1 <br />Particle acceleration (in/sZ) =Particle velocity (in/s) x 2 ~ f Equation 1.2 <br />Where: rr = 3.14 <br />f=frequency of motion or cycles per second (Hz) <br />Vibration Intensity Predictions <br />It is standard practice to use scaling relationships to predict vibration intensities at various <br />distances. These relationships, based on similitude theory, are used to develop empirical <br />relationships between particle velocity and distance. The scaling relationship between peak- <br />particle-velocity (PPV) and distance (D) is shown below in Equation 1.3. <br />PPV =x(D)„r Equation 1.3 <br />Where: PPV =Peak Particle Velocity (in/s) <br />D =Distance (ft) <br />W =Maximum Charge-weight-per-delay (Ib) <br />K =Rock Energy Transfer Constan[(K-Factor) <br />m =Decay Constant (negative value) <br />Dr =Scaled Distance (ft-Ib-os) <br />REVEY Associates, Inc. Page 4 of 7 February 2006 <br />