风火山多年冻土隧道施工爆破技术研究
|
摘要
风火山多年冻土隧道是青藏铁路的重点工程,隧道施工中对多年冻土的保护是一项关键技术。施工爆破对冻土的影响主要有两个方面:一是爆破造成围岩损伤,使围岩产生裂隙或使原有裂隙进一步扩展甚至贯通;二是炸药爆炸后产生高温、高压的爆生气体,巨大的热能影响冻土的热平衡关系。为了减小施工爆破对冻土的影响,根据理论分析及现场试验,研究相应的爆破方案,提出在明洞段采用预裂爆破,洞身段采用光面爆破,洞身段IV级围岩采取全断面开挖、V级围岩采用正台阶开挖的合理爆破方案,并优化爆破参数,提出在隧道掘进中对围岩最大爆破振动速度控制在5～10cm/s为宜。为解决施工热扰动问题,采用NaCl盐水炮泥封堵炮孔来达到降温防尘的目的。研究结果表明,水介质对爆生气体的降温效果为55%,而NaCl盐水介质对爆生气体的降温效果高达70%,降温效果十分显著。
The Fenghuoshan Tunnel is an important project in Qinghai—Tibet Railway.How to protect permafrost during tunnelling construction is one of key technologies.There are two kinds of influences on permafrost because of the blasting construction:(1) firstly,blasting results in the damage of the surrounding rock,producing cranny in surrounding rock or making existed cracks spreading even connecting;(2) secondly,the explosion produces gas with high temperature and high pressure,tremendous heat energy influences the heat balance of permafrost.To minimize the effects on permafrost during explosion construction,the research on relevant explosion scheme is conducted based on the theoretical analysis and in-situ test.Presplitting blasting is adopted in the hollow segment;and smooth blasting is adopted in the tunnel body segment.The whole section excavation is considered in the tunnel body segment with surrounding rock grade IV;and the face step excavation is adopted for the tunnel body segment with surrounding rock grade V.Explosion parameters were optimized finally.The maximal explosion vibration velocity in the surrounding rock is controlled at 5–10 cm/s.To solve the heat disturbance problem,brine mud is adopted to block up explosion holes for cool and dustproof.The research result indicated the explosion gaseous cool effect when the brine mud medium was adopted reached 70% compared with 55% when the water mud medium was adopted,so the gaseous cool effect was significant.
The Fenghuoshan Tunnel is an important project in Qinghai—Tibet Railway.How to protect permafrost during tunnelling construction is one of key technologies.There are two kinds of influences on permafrost because of the blasting construction:(1) firstly,blasting results in the damage of the surrounding rock,producing cranny in surrounding rock or making existed cracks spreading even connecting;(2) secondly,the explosion produces gas with high temperature and high pressure,tremendous heat energy influences the heat balance of permafrost.To minimize the effects on permafrost during explosion construction,the research on relevant explosion scheme is conducted based on the theoretical analysis and in-situ test.Presplitting blasting is adopted in the hollow segment;and smooth blasting is adopted in the tunnel body segment.The whole section excavation is considered in the tunnel body segment with surrounding rock grade IV;and the face step excavation is adopted for the tunnel body segment with surrounding rock grade V.Explosion parameters were optimized finally.The maximal explosion vibration velocity in the surrounding rock is controlled at 5–10 cm/s.To solve the heat disturbance problem,brine mud is adopted to block up explosion holes for cool and dustproof.The research result indicated the explosion gaseous cool effect when the brine mud medium was adopted reached 70% compared with 55% when the water mud medium was adopted,so the gaseous cool effect was significant.
引文
[1]徐敩祖，王家澄，张立新.冻土物理学[M].北京:科学出版社,2001.(Xu Xiaozu,Wang Jiacheng,Zhang Lixin.Frozen SoilPhysics[M].Beijing:Science Press,2001.(in Chinese))
[2]沈忠言,张家懿.冻结粉土的动强度特性及其破坏准则[J].冰川冻土,1997,19(2):141–148.(Shen Zhongyan,Zhang Jiayi.Dynamic strength charateristics and failure criterion of frozen silt[J].Journal of Glaciology and Geocryology,1997,19(2):141–148.(inChinese))
[3]张招祥,余群.冻土切削力学特性的试验和理论分析[J].冰川冻土,1994,16(2):104–112.(Zhang Zhaoxiang,Yu Qun.The frozensoil cuts test of the mechanics characteristic and theory analysis[J].Journal of Glaciology and Geocryology,1994,16(2):104–112.(inChinese))
[4]李斌,郑夕健.河面冰破碎比功的研究[J].沈阳建筑工程学院学报,1995,11(3):225–228.(Li Bin,Zheng Xijian.The acting researchfor ratio of ice crash on river surface[J].Journal of ShenyangArchitectural and Civil Engineering Institute,1995,11(3):225–228.(in Chinese))
[5]马芹永.冻土爆破漏斗及冻土爆破性的模型试验研究[J].煤炭学报,1997,22(3):288–293.(Ma Qinyong.Model test of explosioncrater and blastability of frozen soil[J].Journal of China CoalSociety,1997,22(3):288–293.(in Chinese))
[6]宗琦,马芹永.冻土光面爆破参数模型试验研究[J].冰川冻土,1998,20(1):60–63.(Zong Qi,Ma Qinyong.Experimental study onparameters of frozen soil smooth blasting[J].Journal of Glaciologyand Geocryology,1998,20(1):60–63.(in Chinese))
[7]刘清泉.爆破工程师手册[M].北京:煤炭工业出版社,1992.(LiuQingquan.Blasting Engineer′s Manual[M].Beijing:China CoalIndustry Publishing House,1992.(in Chinese))
[8]张雪亮,黄树棠.爆破地震效应[M].北京:地震出版社,1981.(Zhang Xueliang,Huang Shutang.Earthquake Effects Caused byBlasting[M].Beijing:Earthquake Press,1981.(in Chinese))
[9]中华人民共和国国家标准编写组.爆破安全规程(GB6722–86)[S].北京:冶金工业出版社,1986.(The National Standards CompilationGroup of People′s Republic of China.Safety Regulations for BlastingPractices(GB6722–86)[S].Beijing:China Metallurgical IndustryPress,1986.(in Chinese))
[10]顾毅成,冯叔瑜.高原冻土地区路堑爆破开挖施工的基本原则[J].中国铁道科学,2001,22(6):95–99.(Gu Yicheng,Feng Shuyu.Basic principles of railway-trench excavation by blasting in plateaufrost soil zone[J].China Railway Science,2001,22(6):95–99.(inChinese))
[11]杨年华.冻土爆破的实践与认识[J].铁道工程学报,2000,68(4):95–97.(Yang Nianhua.Practices and understandings on blasting offrozen ground[J].Journal of Railway Engineering Society,2000,68(4):95–97.(in Chinese))
[12]齐康平,胡种新.青藏铁路昆仑山隧道综合施工技术[J].现代隧道技术,2003,40(4):41–45.(Qi Kangping,Hu Zhongxin.Generalconstruction technology of Kunlunshan tunnel on Qinghai—TibetRailway[J].Modern Tunnelling Technology,2003,40(4):41–45.(inChinese))
[2]沈忠言,张家懿.冻结粉土的动强度特性及其破坏准则[J].冰川冻土,1997,19(2):141–148.(Shen Zhongyan,Zhang Jiayi.Dynamic strength charateristics and failure criterion of frozen silt[J].Journal of Glaciology and Geocryology,1997,19(2):141–148.(inChinese))
[3]张招祥,余群.冻土切削力学特性的试验和理论分析[J].冰川冻土,1994,16(2):104–112.(Zhang Zhaoxiang,Yu Qun.The frozensoil cuts test of the mechanics characteristic and theory analysis[J].Journal of Glaciology and Geocryology,1994,16(2):104–112.(inChinese))
[4]李斌,郑夕健.河面冰破碎比功的研究[J].沈阳建筑工程学院学报,1995,11(3):225–228.(Li Bin,Zheng Xijian.The acting researchfor ratio of ice crash on river surface[J].Journal of ShenyangArchitectural and Civil Engineering Institute,1995,11(3):225–228.(in Chinese))
[5]马芹永.冻土爆破漏斗及冻土爆破性的模型试验研究[J].煤炭学报,1997,22(3):288–293.(Ma Qinyong.Model test of explosioncrater and blastability of frozen soil[J].Journal of China CoalSociety,1997,22(3):288–293.(in Chinese))
[6]宗琦,马芹永.冻土光面爆破参数模型试验研究[J].冰川冻土,1998,20(1):60–63.(Zong Qi,Ma Qinyong.Experimental study onparameters of frozen soil smooth blasting[J].Journal of Glaciologyand Geocryology,1998,20(1):60–63.(in Chinese))
[7]刘清泉.爆破工程师手册[M].北京:煤炭工业出版社,1992.(LiuQingquan.Blasting Engineer′s Manual[M].Beijing:China CoalIndustry Publishing House,1992.(in Chinese))
[8]张雪亮,黄树棠.爆破地震效应[M].北京:地震出版社,1981.(Zhang Xueliang,Huang Shutang.Earthquake Effects Caused byBlasting[M].Beijing:Earthquake Press,1981.(in Chinese))
[9]中华人民共和国国家标准编写组.爆破安全规程(GB6722–86)[S].北京:冶金工业出版社,1986.(The National Standards CompilationGroup of People′s Republic of China.Safety Regulations for BlastingPractices(GB6722–86)[S].Beijing:China Metallurgical IndustryPress,1986.(in Chinese))
[10]顾毅成,冯叔瑜.高原冻土地区路堑爆破开挖施工的基本原则[J].中国铁道科学,2001,22(6):95–99.(Gu Yicheng,Feng Shuyu.Basic principles of railway-trench excavation by blasting in plateaufrost soil zone[J].China Railway Science,2001,22(6):95–99.(inChinese))
[11]杨年华.冻土爆破的实践与认识[J].铁道工程学报,2000,68(4):95–97.(Yang Nianhua.Practices and understandings on blasting offrozen ground[J].Journal of Railway Engineering Society,2000,68(4):95–97.(in Chinese))
[12]齐康平,胡种新.青藏铁路昆仑山隧道综合施工技术[J].现代隧道技术,2003,40(4):41–45.(Qi Kangping,Hu Zhongxin.Generalconstruction technology of Kunlunshan tunnel on Qinghai—TibetRailway[J].Modern Tunnelling Technology,2003,40(4):41–45.(inChinese))
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心