Demolition of a Bridge by Controlled Blasting and the Effect of Precutting Measure

The technology of precutting is an important measure to rise the effect of controlled blasting and improve the rate of result-cost.The blasting scheme,parameters design and the application of safety measure of controlled blasting demolition a bridge in complex environment are introduced.The different blasting results of using precutting measure or no using are compared and analysis.The result indicates:base the disintegrated and smashed effects which are introduced by the dead weight of bridge when the bridge has lost stability.The smashed degree of using precutting measure bridge is up to 80%.The time of using mechanize is low to 3 h.A good results of blasting and economics have been achieved.