This study presents the blasting demolition scheme, the blasting parameters design and the blasting damage control of the 382m long Egret Bay Ribbed slab stone arch bridge in Zhangjiajie City. Considering the larger diameter of 3-5 meters of the pier column and the alignment of intensive steel bars within the bent cap as the main bearing part, the geological drilling rigs equipped with the alloy core drills were used to demolish the reinforced concrete of bent cap in the drilling operation and then replaced by the caterpillar down-the-hole drill to accomplish the subsequent drilling process for the pier column. The employed method can successfully overcome the difficulties which may arise in lateral drilling of the pier column due to the high water level. Deep-hole blasting technology has no impact on the surrounding buildings and the base of downstream hydropower station when v = 1.430cm/s and pm = 0. 013MPa were chosen via safety checking calculation.%介绍了长为382 m的张家界市鹭鸶湾板肋石拱桥的深孔爆破拆除方案、参数设计论证和爆破危害控制措施.针对板肋石拱桥的主要承重部位桥墩立柱直径为3 ～5m且钢筋密集的特点,在桥墩立柱钻孔中,采用地质钻机配套合金岩芯钻头抽取盖梁钢筋混凝土,待穿过盖梁层后,再改用履带式潜孔钻机完成桥墩立柱钻孔,解决了因桥墩盖梁钢筋密集不易钻孔和桥墩立柱高水位无法侧向钻孔的难题.采用深孔爆破技术,经安全校核计算后,v=1.430cm/s,pm=0.013MPa,对周边建(构)筑物和下游水电站基础没有影响.
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