武康铁路二线襄胡段工程Ⅳ标段
路基石方控制爆破
施工方案
中铁六局北京铁建公司武康线项目经理部
二○○五年十月
目 录
1、工程概况 ··················································································································· 2 2、爆破施工方案设计 ··································································································· 2 2.1 工程特点 ·················································································································· 2 2.2 设计原则 ·················································································································· 3 2.3 爆破设计 ·················································································································· 3 2.3.1 爆破方案 ··············································································································· 3 2.3.2 爆破参数设计 ······································································································· 3 2.3.3 药量计算 ··············································································································· 4 3、施工工艺 ··················································································································· 5 3.1 不同情况下的开挖方法 ·························································································· 5 3.1.1 爆破顺序 ··············································································································· 5 3.1.2 开挖顺序安排 ······································································································· 5 3.2 施工准备 ·················································································································· 6 3.3 钻孔 ·························································································································· 6 3.4 装药与堵塞 ·············································································································· 6 3.4.1 装药 ······················································································································· 7 3.4.2 堵塞 ······················································································································· 7 3.5 起爆网络 ·················································································································· 7 4、安全与防护 ··············································································································· 8 4.1 爆破防护 ·················································································································· 8 4.1.1 覆盖防护 ··············································································································· 8 4.1.2 全封闭钢管排架防护体系 ··················································································· 8 4.2 安全措施 ·················································································································· 9 4.2.1 施工安全措施 ······································································································· 9 4.2.2安全组织措施 ········································································································ 9
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路基石方控制爆破施工方案
1、工程概况
本段路基DzK77+260~DzK108+280既有线路堑扩宽石方爆破开挖工程，该段路基开挖岩体为粉质粘土、石英云母片岩。石方爆破开挖段地形条件复杂，山坡陡，周围环境极其复杂，下部紧邻既有线电化铁路，距接触网最近距离小于2.0m，部分地段陡坡脚下为既有桥墩，见图1。
2m 爆 破 区
图1 周围环境示意图
2、爆破施工方案设计 2．1 工程特点
（1） 周围环境极其复杂，部分地段上有高压电线，中部紧贴电气线，下部紧邻既有电化铁路线，施工技术难度大。
（2） 武康线运输繁忙，不可能开天窗爆破施工，要求爆破必须保证既有线运营安全。
（3） 工期紧，爆破方量大。
（4） 施工环境差，工作面少，施工场地狭窄，给爆破开挖增加了很大困难。 （5） 为了保证既有线安全，防止飞石、滚石危及既有线行车安全，要求防护措
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施坚固安全。 2．2 设计原则
根据地形地质条件，结合工程特点，设计原则如下：
（1） 不能采用一般爆破方法进行爆破施工，必须采用石方控制爆破进行施工。 （2） 为保证边坡稳定，边坡采用预裂爆破技术施工，采用从上到下、从两端向中间、从里向外进行浅孔台阶控制爆破设计施工。
（3） 根据爆破安全规定，在电化铁路扩堑施工中，采用非电毫秒导爆雷管微差起爆网络施工。
（4） 整个爆破地点不允许有扬起物，装药后必须用钢丝网上覆砂袋覆盖。 （5） 整个爆破过程需用时间见下表：
装药 30min
2.3 爆破设计 2.3.1 爆破方案选择
（1） 爆破方案：
为确保爆破施工安全，减少对既有线行车的干扰，根据地形地质条件与周围环境特点，总体选择多循环、小规模浅孔控制爆破开挖方案。石方开挖施工采取自两端沿线路纵向逐层对向推进，外侧（靠近既有线侧）预留1.0～2.0m厚隔墙，先内侧拉槽，后外侧薄层剥离，自上而下的爆破方法。人工清碴集堆，机械倒运清除。
（2） 施工程序
施工准备→平整钻孔场地→搭建防护排架→钻孔爆破→爆碴清运。 2.3.2 爆破参数设计
（1） 爆破参数选择（见表1）
爆破参数表 表1
爆破 类型 一般浅孔 控制爆破 台阶 高度 H(m) 2~3 底板 抵抗线 W1 (m) 1.2~1.5 0.8~1.0 孔距 a(m) 1.0~1.2 0.8~1.0 排距 b(m) 0.8~1.0 0.6~0.8 孔深 L(m) 2.5~3.5 1.2~1.5 超钻 深度 h(m) 0.5~0.8 0.3 单位 用药量 k(kg/m3) 0.3~0.35 0.2 备注 适于拉槽部分 隔墙 3
覆盖物 20min 起爆 10min 清场 60min 严格浅孔 1~1.5