Abstract
This study aims to propose a new predictor of the vibration level of blasting vibrations. The level must be measured by a vibration level meter that satisfies JIS (JIS C1510). We first researched the response characteristics of the level meter, and developed a computer program which could simulate those characteristics. Using the program. we investigated the effect of the delay on the level. In the investigation, we assumed that the delay blasting was made up of a series of single shot blasting with a time delay. Intermitted sine waves were used as idealized delay blasting waves as well as observed waves.
On the assumption that frequency is more than 8Hz, and time delay (Ti) is longer than duration time we proposed a new practical predictor for the vibration level as a function of Ti and peak particle velocity (PPV).The PPV is easily estimated from the well known predictor.