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Abstract Digital detonator?s delay time is arbitrarily set up according to field requirement and its delay time is very accurate. Digital detonator is one of the most advanced detonators，and is leading the revolution of blasting technology. Several experiments of building tunnels with digital detonator blasting are tried out in Renhechang tunnel of Lanzhou—Chongqing railway，decreasing blasting vibration mechanism with digital detonator is studied. The optimal delay time of blast hole of tunnel is gained；technology of tunnel digital detonator blasting one by one hole is put forward，the blasting vibration is decreased at least 80% in the same blasting advance with detonator blasting with shock-conducting tube，and at least 50% at increasing 25% of blasting advance. Several mixed networks of digital detonator and detonator with shock-conducting tube are tried in order to reduce the blasting cost of tunnel. The optimal joint technology is put forward，the blasting vibration is decreased at least 40% at increasing 25% of blasting advance. The interval between blasting hole delay time greatly affect the result of tunnel blasting，the longer interval between blasting hole delay time result in shorter blasting advance of tunnel and bad fragment，the shorter interval result does not decrease blasting vibration，sometimes increases blasting vibration. The experimental results settle the problem of blasting building railway tunnel in complicated environment，and are also applied to city highway tunnels，the social and economic benefits are acquired. The study result can provide references for tunnel in complicated environment.
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Received: 31 October 2011
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2012, Vol. 31 
