卡鲁玛尾水隧洞出口围堰拆除控制爆破技术  

The controlled blasting technology for cofferdam demolition at Karuma tailrace tunnel outfall

作　　者：杨玉银[1] 张艳如 张荣 韩静 张健鹏[1] YANG Yu-yin;ZHANG Yan-ru;ZHANG Rong;HAN Jing;ZHANG Jian-peng(Sinohydro Bureau 5 Co.,Ltd.,Chengdu 610066,China;Jincheng College of Sichuan University,Chengdu 611731,China)

机构地区：[1]中国水利水电第五工程局有限公司,成都610066 [2]四川大学锦城学院,成都611731

出　　处：《工程爆破》2020年第6期76-83,共8页Engineering Blasting

摘　　要：在乌干达卡鲁玛水电站尾水隧洞出口围堰拆除爆破施工中,为了解决围堰爆破作业面与两侧墙贴坡混凝土距离过近,上覆渣体上钻孔难于成孔,水下开挖底板高程难于保证,水下爆破飞石难于控制,非电毫秒雷管脚线长度不足等问题,采取了在距离两侧墙贴坡混凝土一定范围内采用液压破碎锤和反铲挖除,上覆渣体采用下套管钻孔,水下底板开挖增加钻孔超深,每茬炮爆破时前部覆盖上茬炮渣体,平衡围堰上下游水压,采用低段位雷管孔内接长等措施,成功地对围堰实施了拆除爆破。实践表明,在围堰拆除爆破施工中,针对具体施工存在的问题,结合施工现场实际情况,采取合理的处理措施,均能取得较好的爆破效果。During the cofferdam demolition blasting of tailrace tunnel outfall at Karuma Hydro Power Project in Uganda,some measures,including demolition with hydraulic hammer and excavator in a certain range near to the slope structural concrete,drilling with casing on the backfilled material,drilling with over depth for the bottom excavation,covering current blasting with former blasted material in each blasting cycle,balancing the water pressure at the two sides of cofferdam,and extending length of short delay detonator for deep blasting hole etc.,are taken to solve the problems of short distance between blasting position and structural concrete of the two slope walls,difficulty in drilling holes on backfilled material,difficulty in ensuring the bottom elevation during underwater excavation,difficulty in controlling flying stones during under water blasting and the insufficient length of non-electric millisecond detonator wire.With all the measures taken above,the cofferdam is successfully demolished by blasting method.This practice indicates that during the cofferdam demolition with blasting method,for those problems existing in the construction,better blasting result can be achieved by combing site construction situation and taking reasonable treatment measures.

关 键 词：围堰拆除 控制爆破 水下爆破 尾水隧洞出口 

分 类 号：TD235[矿业工程—矿井建设]