【作者】 于崇；

【导师】 李海波；

【作者基本信息】 中国科学院研究生院（武汉岩土力学研究所） ， 岩土工程， 2010， 博士

【摘要】 随着我国经济的增长,石油资源消费量迅速增加。我国必须建立石油储备体系。出于安全、经济的考虑,有条件的国家和地区都将地下石油储备作为主要的储存方式。对于水封式地下石油储备设计,洞室群围岩稳定性及渗流场分析是两个关键的问题。鉴于此本文依托大连地下石油储备库建设,开展水封式地下石油储备库洞室群围岩稳定性及渗流场分析的研究工作。首先,基于FLAC3D的FISH语言开发平台,利用现场实测地应力结果的回归模型,经过应力变换,直接赋予整个模型单元相应的应力,反演初始地应力场；同时,采用FLAC3D的fl_anisotropic的渗流模型反演库区的初始渗流场,基于随机节理网络模拟技术反应岩体各向异性渗透特征。从而为后续计算提供较合理的初始地应力场和渗流场模型。其次,开展洞室群开挖对库区围岩稳定性和渗流场影响及支护方法分析工作。在水封作用下,针对大连地下石油储备库建设中洞室群的工程特点,考虑应力与渗流的耦合作用实施开挖仿真计算,以获得相应的开挖变形、开挖应力场、开挖塑性区及开挖渗流场。借鉴国外水封效果的评价标准,依据地下水位线和垂直水力坡降的变化评价水封效果。基于点安全系数法,定量的评价洞室群的稳定性。此外,针对大连地下石油储备库建设中可能的局部不良地址情况,依据不同的支护方法进行数值模拟分析,研究不同支护方法下的围岩变形、应力及塑性区情况,评价静力、动力作用下的支护效果。然后,开展储备库洞室群稳定性影响因素分析工作。基于均匀设计,考虑影响洞室群稳定性的岩石力学特性、地应力分布特征、渗透特性、洞跨比等因素,以洞室局部抗剪安全系数即点安全系数作为目标量,建立点安全系数的数理统计模型,分析了各因素对洞室群稳定性的影响规律。再次,开展开挖过程对洞室群围岩稳定性影响分析工作。针对水封式石油储备库洞室内分层开挖和洞室间开挖顺序两方面内容,对比分析各种开挖方法对围岩的应力场、位移场、塑性区的影响,以便选择较优的开挖方案。最后,开展储备库洞室群运营期稳定性分析工作。根据大连地下石油储备库的岩石特性,采用广义开尔文粘弹塑性流变本构模型,模拟在长期荷载作用下了围岩的流变力学行为,分析储油洞室群的长期稳定性。针对储备库建成以后可能遇到的极端天气,由于受季节性雨水补给而造成地下水位的变化,分析库区渗流场的长期特征。此外,分别采用数值分析法和震害调查分析法分析地震荷载作用下地下洞室群围岩稳定性。更多还原

【Abstract】 As China’s economic growth, oil consumption is increasing rapidly. China’s oil storage system must be established. For security, economic considerations, nations and regions which have construction conditions will choose underground oil storage as the main storage means. The rock stability and seepage field analysis are two key issues in the design of water-tight underground oil storge canverns. Facing these problems, the author relies on the the construction project of Da Lian underground oil storge canverns to carry out the research work of rock stability and seepage field analysis.In the first place, based on regression model of site stress test data, directly giving the model element corresponding stress, inversion of initial stress field is completed with the programming language FISH embedded within FLAC3D after stress transformation; meantime, inversion of initial seepage filed is obtained with the model of fl_anisotropic within FLAC3D, anisotropy of permeability is responsed based on joins network simulation technique. The above work provides more reasonable initial stress field and initial seepage filed for posterior calculation.In the next place, the impact of caverns excavation on rock stability and seepage fields are analyzed, immediately, support method analysis. Aim at the engineering characteristics of Da Lian underground oil storge canverns, considering the coupling effect of stress and seepage, the corresponding deformation, stress, plastic zone and seepage are obtained through simulation of excavation. It is to use water level and vertical hydraulic gradient as evaluation criteria of water-tight referring to foreign. Point safety factor method is used to quantificationally evaluate stability of caverns. In addition, Da Lian underground oil storge canverns may have local bad rock mass conditions. Comparing numerical simulation of different support methods, rock deformation, stress and the plastic zone are obtained to assess the static and dynamic support effects.After that, influencing factors of caverns stability are analyzed. Considering rock mechanical properties, stress distribution, permeability properties, the ratio of the width and span and other factors, based on uniform design, statistical model of point safety factor is established. The regularity of the influencing factors are found according to the model.Subsequently, the influence of excavation process on caverns stability are analyzed. On the one hand excavation step, on the other hand excavation sequence. Through comparison of numerical simulation results, it is convenient to select the optimum excavation process.In the end, the operation stability of Da Lian underground oil storge canverns is analyzed. According to rock properties, caverns rheology mechanical behavior is simulated using the generalized Kelvin visco-plastic rheological constitutive model. Considering possible extreme weather, the water supply caused by seasonal changes in groundwater level, the long-term seepage filed is also studied in the operation period. In addition, numerical simulation analysis and Sharma-Judd’s survey analysis methods are used to carry out seismic safety assessment subjected to the earthquake.更多还原