下水库大坝爆破施工方案

广东惠州抽水蓄能电站下水库大坝土建工程编号：GDS2（2005）B2-02-017下水库大坝爆破施工方案广东水电二局股份有限公司惠蓄电站下水库大坝土建工程项目部2005年10月广东惠州抽水蓄能电站下水库大坝土建工程下水库大坝爆破施工方案审核：陆岸典校核：罗兆涛编写：何嘉斌目录1.工程概述·············································································12.编制依据·············································································13.爆破技术方案·······································································13.1.总体方案········································································13.2.爆破设计及参数选择·························································23.2.1.光面爆破······································································23.2.2.预裂爆破孔设计·····························································33.2.3.主炮孔设计···································································43.2.4.浅孔小台阶爆破参数·······················································6附图:1、下库主坝爆破开挖设计图(1/3)························XKZB-KA-BP-012、下库主坝爆破开挖设计图（2/3）····················XKZB-KA-BP-022、下库主坝爆破开挖设计图（3/3）····················XKZB-KA-BP-0311.工程概述主坝为全断面碾压砼重力坝，主坝区强风化带较薄，弱风化花岗岩，埋藏较浅；坝基地层岩性为燕山四期中细粒花岗岩，左岸全风化厚4～12.6m；右岸较薄；两岸强风化厚2.4～4.4m；建基面置于弱分化带上限以下2～2.5m，坝基开挖约下7～25m。下水库大坝主体工程石方开挖工程量见下表工程部位工程项目单位工程量主坝石方开挖m369666槽挖石方m39068洞挖石方m33762.编制依据（1）、《广东惠州抽水蓄能电站下水库大坝土建工程技术条款》（2）、《爆破安全规程》GB6722-86（3）、《水工建筑物岩石基础开挖工程施工技术规范》SL47-943.爆破技术方案3.1.总体方案主坝石方开挖量大，开挖工作宽阔，但坝基开挖规格要求高，主要采用液压，配备手风钻进行规格修整的钻孔。根据主坝开挖揭露的石方地面线进行爆破设计，主要采用深孔梯段爆破及预裂爆破技术，确保坝基的开挖质量。主坝坝基石方爆破，边坡面采用光面爆破或预裂爆破。底板面采用预留1m保护层，保护层采用浅孔少药量进行爆破，并预留30cm为人工撬挖层。光面孔及保护层开挖采用手风钻钻孔。预裂孔及主炮孔采用液压钻钻2孔，梯段高度为3m。坝基上游趾槽先进行开槽，然后对边坡保护层进行光面爆破。3.2.爆破设计及参数选择为了确保开挖面平整光滑，减轻对保留岩体的破坏，减少超欠挖，坝基采用光面爆破或预裂爆破。3.2.1.光面爆破（1）钻孔直径mmd42（2）台阶高度mH3（3）超钻深度mm～h5.0)5.15.0(（4）最小抵抗线mmKdW8404220光2515～K，主坝坝基岩石为强风化，取20K。（5）孔距mmmmWa6008407.0)(光光炮孔密集系数8.06.0～m，一般取0.7。（6）炮孔长度haHLsin/（7）光面爆破装药量计算mgmgWaKq/15284.06.0300)/(光光光光K值根据下表选取：光面爆破与预裂爆破炸药单耗表岩石名称岩石特征岩石坚固系数f值炮孔松动爆破)/(3mgK松光面爆破)/(3mgK光预裂爆破)/(3mgK预花岗岩风化严重、节理裂隙发育、多组节理交割、裂隙频率大于5条/m4～6370～520150～300300～450风化较轻节理不甚发育7～12430～640180～360360～5403未风化，完整致密12～20530～720210～420420～6303.2.2.预裂爆破孔设计（1）炮孔间距cmD～a75908)127(式中：a—炮孔间距，cm；D—钻孔直径，90mm；7～12—系数，当孔径小时，取大值，孔径大时取小值；当岩石均匀完整时，取大值；岩石破碎时，取小值。（2）不偶合系数在预裂爆破设计中，不藕合系数大于2。dDDd式中：Dd—不偶合系数，坚硬岩石选较小值，松软岩石选大值；D、d—分别为钻孔、药卷直径，cm。mmd32（3）线装药密度根据岩石强度和孔距计算：mgaQx/357100060188.0188.05.0Qx—线装药密度，g/m，以全孔长度计；a—炮孔间距，mm；—岩石极限抗压强度，Kgf/cm2、适用200～1500Kgf/cm24（4）装药结构预裂孔装药结构参数表孔深（m）导爆索长（m）孔底装药上部装药全孔药量（kg）堵塞长度（m）长度（m）用量（kg/m）药量（kg）长度（m）用量（kg/m）药量（kg）360.51.00.51.80.420.751.251.2670.51.00.54.00.52.02.61.2装药结构图3.2.3.主炮孔设计主炮孔为直孔，炮孔直径为90mm，见炮孔布置见图。（1）梯段高度mH3（2）钻孔直径mmD900（3）超钻深度h和钻孔深度L对于垂直深孔W～h)35.015.0(对于倾斜深孔W～h)50.030.0(4.322.03hHLh—超钻深度，m；1W—底盘抵抗线，m；W—倾斜钻孔抵抗线（长柱形药包中心到台阶坡面的垂直距离），m；H—台阶高度m；D—钻孔直径。正常段m节x1Ф32乳化炸药@37.5～43cm(m-2)X37.5～43L1加强段1.8kg,1.4m长14012016040减弱段4节1/2XΦ32乳化炸药@40cm3X405（4）按炮孔孔径倍数确定底盘抵抗线mH～W237.0)9.06.0(1（5）炮孔间距a和排距b的确定①孔距mmWa325.11—m密集系数，通常大于1，取m=1.5。②排距ab886.0≈2.5（5）堵塞长度L21275.0WL≈1.51W—底盘抵抗线台阶爆破单位耗药量q值表岩性f值0.8～23～45681012141620)/(3mkgQ0.40.430.460.50.530.560.60.640.670.7（5）爆破装药量计算①根据地质报告,下水库主坝区强风化带埋藏深，弱风化岩石饱和单轴抗压强度为98Mpa。8.910Rf，选取3/56.0mkgQkgqabHQ6.1235.2356.0②当岩石节理发育的强风化岩石时，取5f，取3/46.0mkgQkgqabHQ35.1035.2346.06（6）装药结构主炮孔装药结构参数表孔深（m）孔底装药中部装药上部装药全孔药量（kg）堵塞长度（m）长度（m）线密度（kg/m）药量（kg）长度（m）线密度（kg/m）药量（kg/m）长度（m）线密度（kg/m）药量（kg）318814.64.612.6261.5812155173.53.2.4.浅孔小台阶爆破参数对局部难以采用液压钻或潜孔钻进行钻孔的部位，拟采用手风钻钻孔。（1）最小抵抗线mH～W2.126.0)0.14.0(（2）孔距mW～a2.12.11)0.20.1(（3）排距ma～b12.18.0)0.18.0(（4）孔深HL▽h=2.2（5）炮孔超深▽h～h)15.01.0(=0.2（6）堵塞长度wl'=1.3（7）炸药单耗3/)8.03.0(mkg～q浅孔小台阶爆破主要参数孔径(mm)台阶高(m)孔深(m)抵抗线(m)孔间距(m)堵塞(m)装药量(m)单耗(m)420.30.60.40.50.50.051.25420.40.60.40.50.50.050.83420.60.90.50.650.80.10.51420.81.10.60.750.90.20.56421.01.40.81.01.00.40.5421.52.01.01.21.20.850.47422.02.61.31.61.31.70.41422.53.21.51.91.52.70.38