在建坝体中部分浆砌石的控制爆破拆除

某在建大坝部分浆砌石坝体因质量不合格须爆破拆除。保护余留坝体免受爆破影响是此工程的重点,为此,采用了小直径浅孔和微差爆破分层拆除方法,被拆除部分和被保护部分之间预留保护层。爆破施工过程中,利用超声波观测法和压水试验法判断被保护坝体是否受到了爆破震动的影响。根据判断结果,调整爆破参数,以减小爆破震动。文中论述了爆破参数的选择、保护层厚度的确定,同时介绍了安全控制技术、测点布置以及监测结果。

DEMOLITION OF PARTIAL MORTAR RUBBLE IN A DAM UNDER CONSTRUCTION BY CONTROLLED BLASTING

A portion of mortar rubble in a dam under construction is necessary to be demolished by controlled blasting due to its unqualified qualityThe focus of this project is to protect the remained dam body against the effect of demolition blastingFor this reason,a layer by layer demolition method using short holes and millisecond blasting is adopted and the protecting layers between the part to be demolished and the part to be protected are remained in advanceIn the process of blasting implementation,the ultrasonic inspection and pressure water method are used to judge whether the dam body to be protected is subjected to the effect of blastingAccording to the judgment,the blasting parameters are adjusted so as to reduce blasting vibrationIn this paper,the selection of blasting parameters and determination of the thickness of a protecting layer are discussedAt the same time,the safety precautions,measuring point arrangement and monitoring results are presented