引汉济渭工程秦岭输水隧洞初始地应力场特征及反演分析
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摘要
针对秦岭输水隧洞大埋深、高地应力容易引起岩爆、大变形等工程灾害的问题,为预防和减轻地应力分布和变化对施工进程和人员设备安全的不利影响,对秦岭隧洞隧址区典型位置(越岭段、岭南、岭北)分别进行了水压致裂法应力测试,并对无断层段和含断层段进行了三维地应力场反演分析,研究了秦岭隧洞初始地应力场特征及规律。结果表明:秦岭隧洞地应力表现出较强的水平构造应力作用,岭南岭北勘探试验最大主应力为25.4～27.7 MPa,垂直孔测得最大水平主应力方向稳定在近EW向。数值模拟可以较好地反演分析秦岭输水隧洞的地应力分布,无断层段隧洞最大主应力多为10～45 MPa,最小主应力多为0～15 MPa;含断层段隧洞主轴最大水平主应力值较高,变化范围为20.46～71.94 MPa,最高达71.94 MPa。由于断层破碎带的存在,附近区域会出现剧烈的应力变化,断层带以内应力值显著减小,而断层带两侧出现应力集中,局部应力值升高。
Aiming at the problem of that the engineering disasters of rock burst, large deformation, etc. are prone to be caused by the buried depth and high geostress of Qinling Water Conveyance Tunnel, the stress testings on the hydraulic fracturing method are carried out on the typical locations(the Qinling Mountain-Crossing section, the south section of Qinling Mountain and the north section of Qinling Mountain) at the site of the tunnel respectively, and then the 3-D geostress field inverse analyses of the section without fault and the section with fault are made for studying the characteristics and law of the initial geostress field of Qinling Water Conveyance Tunnel. The study result shows that the geostress of Qinling Water Conveyance Tunnel exhibits stronger tectonic stress effect, while the reconnaissance tests made on the south section of Qinling Mountain and the north section of Qinling Mountain show that the maximum horizontal principal stresses is 25.4～27.7 MPa and the direction of the maximum horizontal principal stress stabilizes to EW. The geostress distribution of Qinling Water Conveyance Tunnel can be better inversely analyzed by the numerical simulation concerned; from which most of the maximum principal stresses of the tunnel section without fault are 10～45 MPa and most of the minimum principal stresses are 0～15 MPa, while the values of the maximum horizontal principal stress along the main axis of the tunnel sections with fault are higher with the variation range of 20.46～71.94 MPa and the maximum is up to 71.94 MPa. Due to the existence of fault fracturing zone, strenuous stress variations are to occur at the areas nearby and the stress value inside the fault zones significantly decrease, but stress concentrations occur at both the sides of fault zones with the increase of local stress.
Aiming at the problem of that the engineering disasters of rock burst, large deformation, etc. are prone to be caused by the buried depth and high geostress of Qinling Water Conveyance Tunnel, the stress testings on the hydraulic fracturing method are carried out on the typical locations(the Qinling Mountain-Crossing section, the south section of Qinling Mountain and the north section of Qinling Mountain) at the site of the tunnel respectively, and then the 3-D geostress field inverse analyses of the section without fault and the section with fault are made for studying the characteristics and law of the initial geostress field of Qinling Water Conveyance Tunnel. The study result shows that the geostress of Qinling Water Conveyance Tunnel exhibits stronger tectonic stress effect, while the reconnaissance tests made on the south section of Qinling Mountain and the north section of Qinling Mountain show that the maximum horizontal principal stresses is 25.4～27.7 MPa and the direction of the maximum horizontal principal stress stabilizes to EW. The geostress distribution of Qinling Water Conveyance Tunnel can be better inversely analyzed by the numerical simulation concerned; from which most of the maximum principal stresses of the tunnel section without fault are 10～45 MPa and most of the minimum principal stresses are 0～15 MPa, while the values of the maximum horizontal principal stress along the main axis of the tunnel sections with fault are higher with the variation range of 20.46～71.94 MPa and the maximum is up to 71.94 MPa. Due to the existence of fault fracturing zone, strenuous stress variations are to occur at the areas nearby and the stress value inside the fault zones significantly decrease, but stress concentrations occur at both the sides of fault zones with the increase of local stress.
引文
[1] 景锋,盛谦,张勇慧,等.我国原位地应力测量与地应力场分析研究进展[J].岩土力学,2011,32(增2):51- 58.
[2] 陈菲,何川,邓建辉.高地应力定义及其定性定量判据[J].岩土力学,2015,36(4):971- 980.
[3] 赵前进.玉磨铁路隧道工程地质特征及地质风险分析[J].铁道勘察,2017,43(4):42- 45.
[4] 王金安,李飞.复杂地应力场反演优化算法及研究新进展[J].中国矿业大学学报,2015,44(2):189- 205.
[5] 李勇,汤达祯,许浩,等.鄂尔多斯盆地柳林地区煤储层地应力场特征及其对裂隙的控制作用[J].煤炭学报,2014,39(增1):164- 168.
[6] 邓金根,陈峥嵘,耿亚楠,等.页岩储层地应力预测模型的建立和求解[J].中国石油大学学报(自然科学版),2013,37(6):59- 64.
[7] 王朋.引汉济渭秦岭深埋特长隧洞高地应力与岩爆关系研究[D].成都:西南交通大学,2014.
[8] 张勇慧,魏倩,盛谦,等.大岗山水电站地下厂房区三维地应力场反演分析[J].岩土力学,2011,32(5):1523- 1530.
[9] 裴启涛,李海波,刘亚群,等.复杂地质条件下坝区初始地应力场二次反演分析[J].岩石力学与工程学报,2014,33(增1):2779- 2785.
[10] 周洪福,王春山,聂德新,等.江坪河水电站坝址区初始地应力场三维数值反演分析[J].水利水电科技进展,2016,36(1):82- 85.
[11] 赵辰,肖明,陈俊涛.复杂地质条件下初始地应力场反演分析方法[J].华中科技大学学报(自然科学版),2017,45(8):87- 92.
[12] 赵大洲,丛苹,崔超,等.引汉济渭工程黄三段输水隧洞围岩变形与压力分析[J].水利水电技术,2017,48(8):59- 62,125.
[13] 曾昭友.水压致裂法测试矿井软岩巷道地应力研究[J].煤炭科学技术,2012,40(12):31- 34.
[2] 陈菲,何川,邓建辉.高地应力定义及其定性定量判据[J].岩土力学,2015,36(4):971- 980.
[3] 赵前进.玉磨铁路隧道工程地质特征及地质风险分析[J].铁道勘察,2017,43(4):42- 45.
[4] 王金安,李飞.复杂地应力场反演优化算法及研究新进展[J].中国矿业大学学报,2015,44(2):189- 205.
[5] 李勇,汤达祯,许浩,等.鄂尔多斯盆地柳林地区煤储层地应力场特征及其对裂隙的控制作用[J].煤炭学报,2014,39(增1):164- 168.
[6] 邓金根,陈峥嵘,耿亚楠,等.页岩储层地应力预测模型的建立和求解[J].中国石油大学学报(自然科学版),2013,37(6):59- 64.
[7] 王朋.引汉济渭秦岭深埋特长隧洞高地应力与岩爆关系研究[D].成都:西南交通大学,2014.
[8] 张勇慧,魏倩,盛谦,等.大岗山水电站地下厂房区三维地应力场反演分析[J].岩土力学,2011,32(5):1523- 1530.
[9] 裴启涛,李海波,刘亚群,等.复杂地质条件下坝区初始地应力场二次反演分析[J].岩石力学与工程学报,2014,33(增1):2779- 2785.
[10] 周洪福,王春山,聂德新,等.江坪河水电站坝址区初始地应力场三维数值反演分析[J].水利水电科技进展,2016,36(1):82- 85.
[11] 赵辰,肖明,陈俊涛.复杂地质条件下初始地应力场反演分析方法[J].华中科技大学学报(自然科学版),2017,45(8):87- 92.
[12] 赵大洲,丛苹,崔超,等.引汉济渭工程黄三段输水隧洞围岩变形与压力分析[J].水利水电技术,2017,48(8):59- 62,125.
[13] 曾昭友.水压致裂法测试矿井软岩巷道地应力研究[J].煤炭科学技术,2012,40(12):31- 34.