岩盐蠕变特性试验研究及理论分析
发布时间：2018-08-16 11:30
【摘要】：岩盐具有很好的隔水性和密封性,力学性质比较稳定,这使它成为建设地下硐室储库的理想介质。我国目前处于盐腔能源储库大规模建设时期,从不同角度研究岩盐蠕变特性,以及探究盐腔储库在长期运行过程中的稳定性是十分必要的。本文通过室内试验、理论分析及计算机模拟等,从不同角度研究了岩盐在不同外界条件下的蠕变力学性质,探讨了其内在机理。①进行了系统的岩盐压缩试验,并通过声发射设备分析岩盐破坏过程中的声发射现象。通过试验得到了该地区岩盐的基本力学参数,探究了不同应力及不同应变速率条件下岩盐的力学特性。通过压缩试验发现该地区岩盐力学性质稳定,离散性很小,多组重复试验得到的极限强度值基本一致。通过分析岩盐压缩过程中的声发射现象,发现在应力峰值处岩盐破坏时单位时间声发射现象最多;在压缩初期声发射现象往往不明显;应变速率越高,单位时间声发射现象数越高,累计声发射现象数越低;在低应变速率条件下压缩初期甚至不会产生声发射现象。利用分形理论分析声发射现象的关联维数特征,发现岩盐在受压过程中关联维数会先呈现上升趋势,在试件破坏前到达峰值,分析声发射现象的关联维数变化趋势可以得到岩盐破坏的预兆信息。②进行了单轴和三轴岩盐蠕变试验,分析轴压、围压及岩盐结构特点对岩盐蠕变的影响。通过蠕变试验发现由大晶粒组成的岩盐蠕变后容易产生大变形,有很好的延性;当围压一定时,轴向压力越大,完成蠕变三个阶段需要的时间越少,试件寿命缩短,稳态蠕变应变率越大;当轴压一定时,增加围压整体上可能降低蠕变应变速度,甚至导致不会出现加速蠕变阶段。③建立了带损伤的岩盐蠕变本构模型,本构模型很好地模拟了岩盐蠕变的加速阶段,通过Matlab拟合材料参数,由本构模型得到的蠕变曲线与试验结果符合较好。④建立了地下盐腔储库模型,运用FLAC 3D分析盐腔储库在长时间周期运行下的稳定性,分析运行内压对盐腔储库稳定性的影响。在极限内压范围内提高运行内压可以增加盐腔的稳定性;计算了不同运行内压及不同运行时间下腔体的最大流变量和溶腔收缩率,判断了盐腔储库在极限内压条件下运行是否安全;计算了盐腔储库的安全系数;确定了盐腔储库腔体间的安全矿柱宽度。
[Abstract]:Rock salt is an ideal medium for building underground cavern storage because of its good water-proof, sealing and stable mechanical properties. At present, China is in the period of large-scale construction of salt cavern energy storage. It is necessary to study the creep characteristics of rock salt from different angles and explore the stability of salt cavern storage in the long-term operation process. In this paper, the creep mechanical properties of rock salt under different external conditions are studied from different angles by laboratory tests, theoretical analysis and computer simulation. The internal mechanism is discussed. 1. Systematic rock salt compression tests are carried out, and acoustic emission phenomena in the process of rock salt failure are analyzed by acoustic emission equipment. The mechanical properties of rock salt under different stress and strain rate conditions are studied. Compression tests show that the mechanical properties of rock salt in this area are stable and the dispersion is very small. The ultimate strength values obtained by repeated tests are basically the same. AE phenomena per unit time are the most common when rock salt is destroyed at the peak value of force; AE phenomena are not obvious at the initial compression stage; AE phenomena per unit time are higher with the increase of strain rate, and the cumulative AE phenomena are lower; AE phenomena are not even produced at the initial compression stage under the condition of low strain rate. It is found that the correlation dimension of rock salt increases at first during compression and reaches its peak value before failure. The prediction information of rock salt failure can be obtained by analyzing the correlation dimension change trend of acoustic emission. 2. Uniaxial and triaxial rock salt creep tests are carried out to analyze axial compression, confining pressure and rock salt structure. The creep tests show that rock salt with large grains tends to produce large deformation and good ductility after creep; when the confining pressure is constant, the greater the axial pressure, the less time it takes to complete the three creep stages, the shorter the life of the specimen, and the greater the steady-state creep strain rate; when the axial pressure is constant, the confining pressure is increased. The creep strain rate may be reduced or even the accelerated creep stage may not occur. 3. The creep constitutive model of rock salt with damage is established, which simulates the accelerated creep stage of rock salt very well. The creep curves obtained from the constitutive model are in good agreement with the experimental results by fitting the material parameters with MATLAB. The stability of salt chamber under long-term operation is analyzed by FLAC 3D, and the effect of internal pressure on the stability of salt chamber is analyzed. The shrinkage rate of the chamber determines whether the salt chamber is safe under the limit internal pressure, calculates the safety factor of the salt chamber, and determines the safe pillar width between the salt chamber chambers.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD315
本文编号：2185854
[Abstract]:Rock salt is an ideal medium for building underground cavern storage because of its good water-proof, sealing and stable mechanical properties. At present, China is in the period of large-scale construction of salt cavern energy storage. It is necessary to study the creep characteristics of rock salt from different angles and explore the stability of salt cavern storage in the long-term operation process. In this paper, the creep mechanical properties of rock salt under different external conditions are studied from different angles by laboratory tests, theoretical analysis and computer simulation. The internal mechanism is discussed. 1. Systematic rock salt compression tests are carried out, and acoustic emission phenomena in the process of rock salt failure are analyzed by acoustic emission equipment. The mechanical properties of rock salt under different stress and strain rate conditions are studied. Compression tests show that the mechanical properties of rock salt in this area are stable and the dispersion is very small. The ultimate strength values obtained by repeated tests are basically the same. AE phenomena per unit time are the most common when rock salt is destroyed at the peak value of force; AE phenomena are not obvious at the initial compression stage; AE phenomena per unit time are higher with the increase of strain rate, and the cumulative AE phenomena are lower; AE phenomena are not even produced at the initial compression stage under the condition of low strain rate. It is found that the correlation dimension of rock salt increases at first during compression and reaches its peak value before failure. The prediction information of rock salt failure can be obtained by analyzing the correlation dimension change trend of acoustic emission. 2. Uniaxial and triaxial rock salt creep tests are carried out to analyze axial compression, confining pressure and rock salt structure. The creep tests show that rock salt with large grains tends to produce large deformation and good ductility after creep; when the confining pressure is constant, the greater the axial pressure, the less time it takes to complete the three creep stages, the shorter the life of the specimen, and the greater the steady-state creep strain rate; when the axial pressure is constant, the confining pressure is increased. The creep strain rate may be reduced or even the accelerated creep stage may not occur. 3. The creep constitutive model of rock salt with damage is established, which simulates the accelerated creep stage of rock salt very well. The creep curves obtained from the constitutive model are in good agreement with the experimental results by fitting the material parameters with MATLAB. The stability of salt chamber under long-term operation is analyzed by FLAC 3D, and the effect of internal pressure on the stability of salt chamber is analyzed. The shrinkage rate of the chamber determines whether the salt chamber is safe under the limit internal pressure, calculates the safety factor of the salt chamber, and determines the safe pillar width between the salt chamber chambers.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD315
【相似文献】
相关期刊论文 前10条
1 余冬梅;虎啸天;付江涛;李光莹;胡夏嵩;;岩盐物理力学性质及其工程稳定性应用现状及其展望[J];盐湖研究;2013年03期
2 魏勇;;浅谈先导井在岩盐定向水平对接井中的应用[J];中国井矿盐;2012年03期
3 宋光福;深埋厚层岩盐全封闭分段开采的可行性[J];中国井矿盐;1994年06期
4 潘海峰;察尔汗盐湖岩盐层渗透性初探[J];化工矿山技术;1995年03期
5 任德能;;对南充蓬莱等地深层岩盐开采问题的探讨[J];井矿盐技术;1983年03期
6 周训发;岩盐开采中几个问题的探讨[J];中国井矿盐;1992年04期
7 潘海峰;察尔汗盐湖岩盐层渗透性的初步研究[J];勘察科学技术;1995年04期
8 邱贤德,邵明康,张兰,姜永东;岩盐流变特性与工程应用研究[J];中国井矿盐;2004年06期
9 周强;柯峰;秦璐;;河南水文一队在濮阳发现岩盐资源43亿吨[J];资源导刊;2010年11期
10 潘海峰;察尔汗盐湖岩盐层渗透性的初步研究[J];军工勘察;1995年03期
相关博士学位论文 前1条
1 汤艳春;考虑岩盐应力与溶解耦合效应的盐腔溶腔机理研究[D];中国科学院研究生院（武汉岩土力学研究所）;2007年
相关硕士学位论文 前6条
1 张天才;岩盐蠕变特性试验研究及理论分析[D];重庆大学;2015年
2 廖f ;使用型盐作为岩盐造腔相似材料实验研究[D];重庆大学;2012年
3 周玉鑫;含夹层岩盐储库渗透性与密闭性研究[D];河北工业大学;2011年
4 赵延林;层状岩盐储库气体渗漏固气耦合模型及储库稳定性研究[D];太原理工大学;2006年
5 赵增欣;含夹层岩盐非线性差异变形解析与储库稳定性研究[D];河北工业大学;2011年
6 刘彦东;察尔汗岩盐路基细观溶蚀试验及其病害防治措施研究[D];兰州理工大学;2014年
，本文编号：2185854
本文链接：https://www.wllwen.com/kejilunwen/kuangye/2185854.html
