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11lasting impact%and tttxk Slope Stability Assmvnew for t.'ommwood Quarry in Gitwxl Cbunty« <br /> Historical NYC Vibration Data Plot <br /> l <br /> 10,00 9►5%Curve; ppV=46 6(D/W°-5)'t-1A <br /> 1.00 -- - . _ - _ <br /> • • Camegie <br /> 0. 010 • Can-Ed <br /> a ■ <br /> r Hunter <br /> !; Did <br /> 0-01 <br /> 0.00 <br /> 1.00 10.00 10000 1000.E <br /> Scaled Distance <br /> Figure 3.4—Historical NYC Scaled Distance--M Data from Blasting at Carnegie Veit,the Con-t-Amn Shaft at <br /> 36"' Strom and l" Avenue and foundation blasting at Hunter College at between 38*anti 39" Streets (NOTE: the <br /> 93%etrrve nicams that 95 percent of the time.predicted values will he lower than the value calculated), <br /> When site-specific historical data is not available, the K factor value can be estimated based on <br /> physical neck properties and degree of blast confinement. From the author's past experience, for <br /> blasts in the igneous rock formations at the Cottonwood site, a prediction equation with a ti <br /> factor of 240 can be used to predict vibration intensities (PPV) at various locauons of concern. <br /> With this cautiously high K-factor, predicted levels of vibration will likely be higher than actual <br /> values measured at similar scaled distances. The resulting prediction equation, which is used in <br /> the site-specific evaluations to Section 4 of'this report,is shown Equation 3.3 below. <br /> PPS' = 240(D/ W) l t, Equation 3.3 <br /> 3.6 Human Response to Transient Vibrations <br /> In addition to concerns about vibration damage, under certain conditions, humans and animals <br /> can be startled or annoyed by blast-induced ground vibration, Research has also shown that the <br /> human response to transient vibration--like those caused by blasting•-variety depending on <br /> cxrK)sure time and the intensity of the. motion. Response curves defining how humans respond to <br /> transient vibrations based on these variables are shown in Figure 3.5. <br /> REVEY A%wciatrs, Inc. page It1 April 2004 <br />