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Abstract Elevation amplification effect of blasting vibration is an important study content of vibration propagation law on rock slope. Based on the theoretical analysis of elevation response mechanism on rock slope，numerical simulation of blasting vibration induced by slope excavation and measured data analysis，the blasting vibration elevation amplification effect has been studied. The results indicate that the blasting vibration elevation amplification effect occurs under some conditions and it is affected by factors such as the property of blasting vibration and the slope form. Under the blasting load，when the natural frequencies of different slope benches correspond with the main frequency band of blast load，the“whiplash effects” are caused in rock structures of the slope benches and the vibrations are amplified. While slope form changes rapidly and slope gradient increase，the vibration velocity of higher slope bench may be larger than that of lower slope bench，which generates significant elevation amplification effect of vibration. Under the similar slope form，the vibration velocity at the toe of slope bench decreases with the increase of the elevation and the elevation amplification effect of vibration is not caused. Under the“whiplash effect”，the vibration velocity at the edge of the slope bench is bigger than that at the toe of slope bench on the same elevation；but the stress and strain are smaller. So the vibration velocities at the edge of the slope bench are not appropriate for evaluating the stability of rock slope.
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Received: 04 May 2011
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2011, Vol. 30 
