岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2015年
z1期
3223-3229
,共7页
爆炸力学%立井%坚硬岩石%大直径空孔%直眼掏槽%爆炸应力场%数值模拟
爆炸力學%立井%堅硬巖石%大直徑空孔%直眼掏槽%爆炸應力場%數值模擬
폭작역학%립정%견경암석%대직경공공%직안도조%폭작응력장%수치모의
blasting mechanics%vertical shaft%hard rock%large diameter cavity%parallel cut%blasting stress field%numerical simulation
为提高立井井筒坚硬岩石段掘进施工的爆破效率,设计在两阶同深桶形直眼掏槽中心布置一个直径100 mm的空孔。根据理论计算和工程实践经验选定掏槽爆破参数,一阶掏槽孔圈径1700 mm、间距850 mm,二圈掏槽孔圈径2500 mm、间距650 mm。运用有限元软件LS-DYNA对一阶掏槽孔爆破后的爆炸应力场进行数值模拟分析和爆破参数合理性验证。模拟结果表明:增加的中心大直径空孔能够提高爆炸应力波峰值和延长作用时间,空孔周围岩体中应力波峰值为无空孔时的2.2倍。同时,数值模拟还更直观地表现直眼掏槽时爆炸应力波在空孔处的应力叠加和反射拉伸现象、以及空孔具有的导向作用。在此基础上,进行立井坚硬岩石段掘进深孔爆破现场试验研究,取得在坚固性系数f=12~17的岩石中平均炮眼利用率达91.7%、爆破块度均匀的良好效果。
為提高立井井筒堅硬巖石段掘進施工的爆破效率,設計在兩階同深桶形直眼掏槽中心佈置一箇直徑100 mm的空孔。根據理論計算和工程實踐經驗選定掏槽爆破參數,一階掏槽孔圈徑1700 mm、間距850 mm,二圈掏槽孔圈徑2500 mm、間距650 mm。運用有限元軟件LS-DYNA對一階掏槽孔爆破後的爆炸應力場進行數值模擬分析和爆破參數閤理性驗證。模擬結果錶明:增加的中心大直徑空孔能夠提高爆炸應力波峰值和延長作用時間,空孔週圍巖體中應力波峰值為無空孔時的2.2倍。同時,數值模擬還更直觀地錶現直眼掏槽時爆炸應力波在空孔處的應力疊加和反射拉伸現象、以及空孔具有的導嚮作用。在此基礎上,進行立井堅硬巖石段掘進深孔爆破現場試驗研究,取得在堅固性繫數f=12~17的巖石中平均砲眼利用率達91.7%、爆破塊度均勻的良好效果。
위제고립정정통견경암석단굴진시공적폭파효솔,설계재량계동심통형직안도조중심포치일개직경100 mm적공공。근거이론계산화공정실천경험선정도조폭파삼수,일계도조공권경1700 mm、간거850 mm,이권도조공권경2500 mm、간거650 mm。운용유한원연건LS-DYNA대일계도조공폭파후적폭작응력장진행수치모의분석화폭파삼수합이성험증。모의결과표명:증가적중심대직경공공능구제고폭작응력파봉치화연장작용시간,공공주위암체중응력파봉치위무공공시적2.2배。동시,수치모의환경직관지표현직안도조시폭작응력파재공공처적응력첩가화반사랍신현상、이급공공구유적도향작용。재차기출상,진행립정견경암석단굴진심공폭파현장시험연구,취득재견고성계수f=12~17적암석중평균포안이용솔체91.7%、폭파괴도균균적량호효과。
For improve drilling and blasting excavation efficiency of vertical shaft hard rock section,design a large diameter cavity in center of same deep of two section parallel cut blasting. According to theoretical calculation and practical experience choose cut blasting parameters,circle diameter of the first section cut hole is 1 700 mm and it′s hole space is 850 mm,the second section cut hole circle diameter is 2 500 mm with hole space 650 mm. Finite element software LS-DYNA is used for blasting stress field of first section cut blasting numerical simulation analysis and blasting parameters rationality verification. The numerical simulation results show that large diameter cavity in center can improve stress peak value and extend action time,stress wave of rock around large diameter cavity is 2.2 times than the value of rock without cavity. At the same time,numerical simulation show stress wave superposition and reflection,guiding phenomena during large diameter cavity of parallel cut. Then deep-hole blasting field research for vertical shaft hard rock section is done,obtained good effect of average utilization rate 91.7%,lumpiness uniform in rock stability coefficientf = 12–17.