Tunnelconstruction

隧道施工

任務(wù)四光面爆破Task4Smoothblasting項目四隧道開挖Project4Tunnelexcavation2知識目標(biāo)通過本任務(wù)的學(xué)習(xí)，學(xué)生應(yīng)掌握隧道光面爆破參數(shù)確定方法；熟悉光面爆破技術(shù)標(biāo)準(zhǔn)，了解光面爆破特點。KnowledgeobjectivesThroughthestudyofthistask,studentsshouldmasterthedeterminationmethodoftunnelsmoothblastingparameters;Befamiliarwiththetechnicalstandardsofsmoothblastingandunderstandthecharacteristicsofsmoothblasting.學(xué)習(xí)目標(biāo)

Learningobjectives3能力目標(biāo)通過本任務(wù)的學(xué)習(xí)，學(xué)生應(yīng)具備選定隧道光面爆破參數(shù)的能力。具有踏實肯干的精神。AbilityobjectivesThroughthestudyofthistask,studentsshouldhavetheabilitytoselecttunnelsmoothblastingparameters.Haveadown-to-earthandwillingspirit.學(xué)習(xí)目標(biāo)

Learningobjectives在隧道爆破施工中，首要的要求是開挖輪廓與尺寸準(zhǔn)確，對圍巖擾動小。所以，周邊眼的爆破效果，反映了整個隧道爆破的成洞質(zhì)量。隧道控制爆破是指光面爆破和預(yù)裂爆破。Intunnelblastingconstruction,theprimaryrequirementisthattheexcavationcontourandsizeareaccurateandthedisturbancetosurroundingrockissmall.Therefore,theblastingeffectofperipheralholesreflectstheholeformingqualityofthewholetunnelblasting.Tunnelcontrolledblastingreferstosmoothblastingandpresplittingblasting.一、光面爆破定義

Ⅰ.Definitionofsmoothblasting通過一系列措施對開挖部位的周邊實行正確的鉆孔和爆破，并使周邊眼最后起爆的爆破方法。Throughaseriesofmeasures,thecorrectdrillingandblastingshallbecarriedoutaroundtheexcavationpart,andtheblastingmethodofmakingthesurroundingholedetonatefinally.二、光面爆破標(biāo)準(zhǔn)

Ⅱ.Smoothblastingstandard2.隧道光面爆破標(biāo)準(zhǔn)開挖輪廓成形規(guī)則，巖面平整;圍巖壁上保存有50%以上的半面炮眼痕跡；無明顯的爆破裂縫;超欠挖符合規(guī)定要求，圍巖壁上無危石等。2.standardforsmoothblastingoftunnelTheexcavationprofileisregularandtherocksurfaceisflat;Therearemorethan50%ofthehalffacegunholesonthewallofthesurroundingrock;Thereisnoobviouscrackinblasting;Overandunderexcavationmeetstherequirements,andthereisnodangerousrockonthewallofsurroundingrock.三、光面爆破參數(shù)

Ⅲ.Parametersofsmoothblasting1.周邊炮眼間距E?？刂浦苓呡喞€，一般取E=（10～18）d例如炮眼直徑為40mm時，則E=300-700mm。完整性的巖石E宜取大值，堅硬和節(jié)理裂隙發(fā)育的巖石E宜取小值；1.PeripheralblastholespacingE.Controltheperipheralcontour,generallye=(10~18)dForexample,whentheholediameteris40mm,e=300-700mm.Therockewithintegrityshouldbetakenasthelargevalue,andtherockewithhardandjointfissuredevelopmentshouldbetakenasthesmallvalue;1.周邊炮眼間距E。也可以按照下表選取，首先判斷圍巖是硬質(zhì)巖還是軟巖，根據(jù)圍巖完整性程度進行選擇。一般周邊眼間距按照5的倍數(shù)進行選擇。1.PeripheralblastholespacingE.Youcanalsoselectaccordingtothefollowingtable,First,judgewhetherthesurroundingrockissoftorhardaccordingtotheintegrityofthesurroundingrock.Generally,theperipheraleyespacingisselectedaccordingtothemultipleof5.三、光面爆破參數(shù)

Ⅲ.Parametersofsmoothblasting3.隧道光面爆破的主要參數(shù)(2)光面層厚度及炮眼密集系數(shù)。K=E/W<1；K=0.8左右較為適宜W=60~90cm3.Mainparametersoftunnelsmoothblasting(2)Thicknessofsmoothsurfacelayerandblastholedensitycoefficient.K=E/W<1；K=0.8ismoreappropriateW=60~90cm一、光面爆破

Ⅰ.Smoothblasting3.隧道光面爆破的主要參數(shù)(2)光面層厚度及炮眼密集系數(shù)。K=E/W<1；K=0.8左右較為適宜W=60~90cm(3)裝藥量既具有破巖所需的能量，又不造成圍巖的過度破壞。軟巖：40~150g/m硬巖：250~400g/m3.Mainparametersoftunnelsmoothblasting(2)Thicknessofsmoothsurfacelayerandblastholedensitycoefficient.K=E/W<1；K=0.8ismoreappropriateW=60~90cm(3)ChargequantityItnotonlyhastheenergyrequiredtobreaktherock,butalsodoesnotcauseexcessivedamagetothesurroundingrock.Softrock:40~150g/MHardrock:250~400g/M一、光面爆破

Ⅰ.Smoothblasting一、光面爆破

Ⅰ.Smoothblasting4.隧道光面爆破的技術(shù)措施（1）使用低爆速、低猛度、低密度、傳爆性能好、爆炸威力小的炸藥。（2）采用不偶合裝藥結(jié)構(gòu)。（3）嚴(yán)格掌握與周邊眼相鄰的內(nèi)圈炮眼的爆破效果，為周邊眼爆破創(chuàng)造臨空面。（4）周邊眼應(yīng)盡量做到同時起爆。（5）嚴(yán)格控制裝藥集中度(裝藥量)。二、預(yù)裂爆破

Ⅱ.

Presplittingblasting1.定義讓周邊眼最先起爆，沿周邊眼連線形成預(yù)裂面，最后在起爆其他炮眼，進而控制巖體的開挖輪廓。2.區(qū)別：（1）起爆順序不同光面爆破先引爆掏槽眼，然后輔助眼，最后周邊眼。預(yù)裂爆破先引爆周邊眼，然后掏槽眼，最后輔助眼。Lettheperipheralholesdetonatefirst,formaprecracksurfacealongtheconnectinglineoftheperipheralholes,andfinallydetonateotherblastholes,soastocontroltheexcavationcontouroftherockmass.2.Differences:(1)DifferentinitiationsequenceSmoothblastingfirstdetonatesthecuttinghole,thentheauxiliaryhole,andfinallytheperipheralhole.Presplittingblastingfirstdetonatestheperipheralhole,thencutsthehole,andfinallytheauxiliaryhole.二、預(yù)裂爆破

Ⅱ.

Presplittingblasting（2）適用條件不同光面爆破適用圍巖穩(wěn)定性好的硬質(zhì)圍巖；預(yù)裂爆破適用穩(wěn)定性較差軟弱圍巖（3）實施過程爆破技術(shù)較光面爆破更為復(fù)雜。(2)DifferentapplicableconditionsSmoothblastingissuitableforhardsurroundingrockwithgoodstability;Presplittingblastingissuitableforweaksurroundingrockwithpoorstability(3)ImplementationprocessBlastingtechnologyismorecomplexthansmoothblasting.隧道光面爆破參數(shù)選擇好之后，就一定能取得很好的爆破效果呢？當(dāng)然不是了，就如同古人常說的“行百里路半九十”，做任何事愈接近成功愈要認(rèn)真對待。Afterthetunnelsmoothblastingparametersareselected,agoodblastingeffectwillb