砂岩循环冻融损伤的低场核磁共振与声发射概率密度研究
|
摘要
为了研究不同水化环境下的砂岩经多次冻融循环后的损伤情况,将饱和蒸馏水与3%NaCl水溶液的砂岩试样,在冻结温度为-30℃、融化温度30℃的环境下进行循环冻融试验;并同步采集冻融中的声发射信号,每3次冻融循环后进行1次低场核磁分析与光学显微观测,在冻融循环结束后再进行单轴压缩试验。试验结果表明:蒸馏水环境和3%NaCl溶液环境作用下,随着冻融循环次数的增加,砂岩试样的T_2谱向右偏移、T_2谱总面积增加、孔隙度增加、内部显微结构破坏,且3%NaCl溶液冻融组变化更为严重;循环冻融后砂岩的单轴压缩声发射绝对能量概率密度依然满足幂定律分布,但临界指数增加,而3%NaCl循环冻融组的增量更大;每次冻融循环过程中,随着循环次数的增加,声发射概率密度的临界指数表现为先增加后降低,与已有的超声波检测试验结果相一致,而融化过程的临界指数峰值超前于结冻过程,冻融损伤主要是因静压、渗透压破坏以及水化介质对岩石的溶解、侵蚀造成的。本研究将为寒区岩体工程损伤破坏机制和稳定性评价提供一定的参考价值。
To study the damage of sandstone in different hydration environment conditions after repeated freeze-thaw cycles, saturated freezing and thawing experiments were carried out on sandstone samples under the freezing temperature of -30 ℃ and melting temperature of 30 ℃. The acoustic emission(AE) signals were recorded during each freezing-thawing cycle, and the microscopic characteristics of sandstone were investigated by low field nuclear magnetic resonance(NMR) and an optical microscope after every three cycles. The uniaxial compression test was conducted at the end of cycles. The results show that since 3% NaCl solution leads to the internal microstructure destruction, with increasing cycle index, the T_2 spectrum shifts to the right, the total area of T_2 spectrum and the porosity increase. The AE absolute energy probability density of sandstone still meets the power law distribution after freeze-thaw cycle under uniaxial compression, but the critical exponent increases and the increment of 3% NaCl is greater than that of distilled water. In addition, the critical exponent of AE probability density for each freezing and thawing cycle increases first and then decreases with increasing cycle number, which is similar to existing ultrasonic testing results. The peak of critical exponent in thawing process is higher than that in freezing process, which means that thawing process has shorter breaking time and a lower damage degree. The freeze-thaw damage is mainly caused by the static pressure, osmotic pressure destruction and dissolution but also the erosion of rock by hydration medium. This study can provide some references for understanding failure mechanism and stability evaluation of rock engineering in cold regions.
To study the damage of sandstone in different hydration environment conditions after repeated freeze-thaw cycles, saturated freezing and thawing experiments were carried out on sandstone samples under the freezing temperature of -30 ℃ and melting temperature of 30 ℃. The acoustic emission(AE) signals were recorded during each freezing-thawing cycle, and the microscopic characteristics of sandstone were investigated by low field nuclear magnetic resonance(NMR) and an optical microscope after every three cycles. The uniaxial compression test was conducted at the end of cycles. The results show that since 3% NaCl solution leads to the internal microstructure destruction, with increasing cycle index, the T_2 spectrum shifts to the right, the total area of T_2 spectrum and the porosity increase. The AE absolute energy probability density of sandstone still meets the power law distribution after freeze-thaw cycle under uniaxial compression, but the critical exponent increases and the increment of 3% NaCl is greater than that of distilled water. In addition, the critical exponent of AE probability density for each freezing and thawing cycle increases first and then decreases with increasing cycle number, which is similar to existing ultrasonic testing results. The peak of critical exponent in thawing process is higher than that in freezing process, which means that thawing process has shorter breaking time and a lower damage degree. The freeze-thaw damage is mainly caused by the static pressure, osmotic pressure destruction and dissolution but also the erosion of rock by hydration medium. This study can provide some references for understanding failure mechanism and stability evaluation of rock engineering in cold regions.
引文
[1]周科平,李杰林,许玉娟,等.冻融循环条件下岩石核磁共振特性的试验研究[J].岩石力学与工程学报,2012,31(4):731-737.ZHOU Ke-ping,LI Jie-lin,XU Yu-juan,et al.Experimental study of NMR characteristics in rock under freezing and thawing cycles[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(4):731-737.
[2]赵卫东,后藤龙彦,杜文斌.冻结溶解条件下抛石材料劣化机制研究[J].岩土工程学报,2002,24(5):663-666.ZHAO Wei-dong,GOTO TATSUHIKO,DU Wen-bin.Study on deteriorating mechanism of riprap material under freezing and thawing condition[J].Chinese Journal of Geotechnical Engineering,2002,24(5):663-666.
[3]NICHOLSON D T,NICHOLSON F H.Physical deterioration of sedimentary rocks subjected to experimental freeze-thaw weathering[J].Earth Surface Processes and Landforms,2000,25(12):1295-1307.
[4]吴刚,何国梁,张磊,等.大理岩循环冻融试验研究[J].岩石力学与工程学报,2006,25(增刊1):2930-2938.WU Gang,HE Guo-liang,ZHANG Lei,et al.Experimental study on cycles of freeze-thaw of marble[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(Supp.1):2930-2938.
[5]俞缙,傅国锋,陈旭,等.冻融循环后砂岩三轴卸围压力学特性试验研究[J].岩石力学与工程学报,2015,34(10):2001-2009.YU Jin,FU Guo-feng,CHEN Xu,et al.Experimental study on mechanical properties of sandstone after freezing-thawing cycles under triaxial confining pressure unloading[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(10):2001-2009.
[6]张慧梅,杨更社.冻融岩石损伤劣化及力学特性试验研究[J].煤炭学报,2013,38(10):1756-1762.ZHANG Hui-mei,YANG Geng-she.Experimental study of damage deterioration and mechanical properties for freezing-thawing rock[J]Chinese Journal of Coal Society,2013,38(10):1756-1762.
[7]张慧梅,杨更社.冻融与荷载耦合作用下岩石损伤模型的研究[J].岩石力学与工程学报,2010,29(3):471-476.ZHANG Hui-mei,YANG Geng-she.Research on damage model of rock under coupling action of freeze-thaw and load[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(3):471-476.
[8]CAI Y Y,YU J,FU G F,et al.Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydro chemical erosion[J].Journal of Mountain Science,2016,13(11):2053-2068.
[9]杨更社,张全胜,蒲毅彬.冻结温度影响下岩石细观损伤演化CT扫描[J].长安大学学报(自然科学版),2004,24(6):40-42.YANG Geng-she,ZHANG Quan-sheng,PU Yi-bin.CTscanning test of meso damage propagation of rock under different freezing temperatures[J].Journal of Chang’an University(Natural Science),2004,24(6):40-42.
[10]张全胜.冻融条件下岩石细观损伤力学特性研究初探[D].西安:西安科技大学,2003.ZHANG Quan-sheng.The preliminary research on meso damage mechanical characteristics of rock under condition of freezing and thawing[D].Xi’an:Xi’an University of Science and Technology,2003.
[11]DE ARGANDONA R V G,REY A R,CELORIO C,et al.Characterization by computed X-Ray tomography of the evolution of the pore structure of a dolomite rock during freeze-thaw cyclic tests[J].Physics and Chemistry of the Earth,Part A:Solid Earth and Geodesy,1999,24(7):633-637.
[12]刘成禹,何满潮,王树仁,等.花岗岩低温冻融损伤特性的实验研究[J].湖南科技大学学报(自然科学版),2005,20(1):37-40.LIU Cheng-yu,HE Man-chao,WANG Shu-ren,et al.Experimental investigation on freeze-thawing damage characteristics of granite at low temperature[J].Journal of Hunan University of Science and Technology(Natural Science),2005,20(1):37-40.
[13]杨全兵.Na Cl溶液结冰压的影响因素研究[J].建筑材料学报,2005,8(5):495-498.YANG Quan-bing.Factors influencing the pressure of ice formation in NaCl solution[J].Journal of Building Materials,2005,8(5):495-498.
[14]肖立志.核磁共振成像测井与岩石核磁共振及其应用[M].北京:科学出版社,1998:1-26.XIAO Li-zhi.NMR imaging logging principles and applications[M].Beijing:Science Press,1998:1-26.
[15]肖立志.岩石核磁共振研究进展及其应用测井技术[J].测井技术,1996,20(1):27-31.XIAO Li-zhi.Recent development on nuclear magnetic resonance in rock samples and its application[J].Well Logging Technology,1996,20(1):27-31.
[16]SALJE E K H,DAHMEN K A.Crackling noise in disordered materials[J].Condensed Matter Physics,2014,5:233-254.
[17]蒋翔,钱昆,王小书,等.基于声发射与NMR的超临界CO2对砂岩力学特性影响研究[J].岩土力学,2018,39(4):1355-1361.JIANG Xiang,QIAN Kun,WANG Xiao-shu,et al.Effect of supercritical CO2 on mechanical properties of sandstone using acoustic emission and NMR[J].Rock and Soil Mechanics,2018,39(4):1355-1361.
[18]KUN F,VARGA I,LENNARTZ-SASSINEK S,et al.Approach to failure in porous granular materials under compression[J].Physical Review E,2013,88(6):062207.
[19]KUN F,VARGA I,LENNARTZ-SASSINEK S,et al.Rupture cascades in a discrete element model of a porous sedimentary rock[J].Physical Review Letters,2014,112(6):065501.
[20]BARóJ,CORRAL A,ILLA X,et al.Statistical similarity between the compression of a porous material and earthquakes[J].Physical Review Letters,2013,110(8):088702.
[21]SETHNA J P,DAHMEN K A,MYERS C R.Crackling noise[J].Nature,2001,410:242-250.
[22]霍润,王强,闫计瑞,等.基于超声波检测的砂岩冻融循环破坏过程[J].沈阳建筑大学学报(自然科学版),2016,32(1):17-24.HUO Run,WANG Qiang,YAN Ji-rui,et al.Study on the failure mechanism of sandstone under freeze-thaw cycles based on the ultrasonic test[J].Journal of Shenyang Jianzhu University(Natural Science),2016,32(1):17-24.
[2]赵卫东,后藤龙彦,杜文斌.冻结溶解条件下抛石材料劣化机制研究[J].岩土工程学报,2002,24(5):663-666.ZHAO Wei-dong,GOTO TATSUHIKO,DU Wen-bin.Study on deteriorating mechanism of riprap material under freezing and thawing condition[J].Chinese Journal of Geotechnical Engineering,2002,24(5):663-666.
[3]NICHOLSON D T,NICHOLSON F H.Physical deterioration of sedimentary rocks subjected to experimental freeze-thaw weathering[J].Earth Surface Processes and Landforms,2000,25(12):1295-1307.
[4]吴刚,何国梁,张磊,等.大理岩循环冻融试验研究[J].岩石力学与工程学报,2006,25(增刊1):2930-2938.WU Gang,HE Guo-liang,ZHANG Lei,et al.Experimental study on cycles of freeze-thaw of marble[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(Supp.1):2930-2938.
[5]俞缙,傅国锋,陈旭,等.冻融循环后砂岩三轴卸围压力学特性试验研究[J].岩石力学与工程学报,2015,34(10):2001-2009.YU Jin,FU Guo-feng,CHEN Xu,et al.Experimental study on mechanical properties of sandstone after freezing-thawing cycles under triaxial confining pressure unloading[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(10):2001-2009.
[6]张慧梅,杨更社.冻融岩石损伤劣化及力学特性试验研究[J].煤炭学报,2013,38(10):1756-1762.ZHANG Hui-mei,YANG Geng-she.Experimental study of damage deterioration and mechanical properties for freezing-thawing rock[J]Chinese Journal of Coal Society,2013,38(10):1756-1762.
[7]张慧梅,杨更社.冻融与荷载耦合作用下岩石损伤模型的研究[J].岩石力学与工程学报,2010,29(3):471-476.ZHANG Hui-mei,YANG Geng-she.Research on damage model of rock under coupling action of freeze-thaw and load[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(3):471-476.
[8]CAI Y Y,YU J,FU G F,et al.Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydro chemical erosion[J].Journal of Mountain Science,2016,13(11):2053-2068.
[9]杨更社,张全胜,蒲毅彬.冻结温度影响下岩石细观损伤演化CT扫描[J].长安大学学报(自然科学版),2004,24(6):40-42.YANG Geng-she,ZHANG Quan-sheng,PU Yi-bin.CTscanning test of meso damage propagation of rock under different freezing temperatures[J].Journal of Chang’an University(Natural Science),2004,24(6):40-42.
[10]张全胜.冻融条件下岩石细观损伤力学特性研究初探[D].西安:西安科技大学,2003.ZHANG Quan-sheng.The preliminary research on meso damage mechanical characteristics of rock under condition of freezing and thawing[D].Xi’an:Xi’an University of Science and Technology,2003.
[11]DE ARGANDONA R V G,REY A R,CELORIO C,et al.Characterization by computed X-Ray tomography of the evolution of the pore structure of a dolomite rock during freeze-thaw cyclic tests[J].Physics and Chemistry of the Earth,Part A:Solid Earth and Geodesy,1999,24(7):633-637.
[12]刘成禹,何满潮,王树仁,等.花岗岩低温冻融损伤特性的实验研究[J].湖南科技大学学报(自然科学版),2005,20(1):37-40.LIU Cheng-yu,HE Man-chao,WANG Shu-ren,et al.Experimental investigation on freeze-thawing damage characteristics of granite at low temperature[J].Journal of Hunan University of Science and Technology(Natural Science),2005,20(1):37-40.
[13]杨全兵.Na Cl溶液结冰压的影响因素研究[J].建筑材料学报,2005,8(5):495-498.YANG Quan-bing.Factors influencing the pressure of ice formation in NaCl solution[J].Journal of Building Materials,2005,8(5):495-498.
[14]肖立志.核磁共振成像测井与岩石核磁共振及其应用[M].北京:科学出版社,1998:1-26.XIAO Li-zhi.NMR imaging logging principles and applications[M].Beijing:Science Press,1998:1-26.
[15]肖立志.岩石核磁共振研究进展及其应用测井技术[J].测井技术,1996,20(1):27-31.XIAO Li-zhi.Recent development on nuclear magnetic resonance in rock samples and its application[J].Well Logging Technology,1996,20(1):27-31.
[16]SALJE E K H,DAHMEN K A.Crackling noise in disordered materials[J].Condensed Matter Physics,2014,5:233-254.
[17]蒋翔,钱昆,王小书,等.基于声发射与NMR的超临界CO2对砂岩力学特性影响研究[J].岩土力学,2018,39(4):1355-1361.JIANG Xiang,QIAN Kun,WANG Xiao-shu,et al.Effect of supercritical CO2 on mechanical properties of sandstone using acoustic emission and NMR[J].Rock and Soil Mechanics,2018,39(4):1355-1361.
[18]KUN F,VARGA I,LENNARTZ-SASSINEK S,et al.Approach to failure in porous granular materials under compression[J].Physical Review E,2013,88(6):062207.
[19]KUN F,VARGA I,LENNARTZ-SASSINEK S,et al.Rupture cascades in a discrete element model of a porous sedimentary rock[J].Physical Review Letters,2014,112(6):065501.
[20]BARóJ,CORRAL A,ILLA X,et al.Statistical similarity between the compression of a porous material and earthquakes[J].Physical Review Letters,2013,110(8):088702.
[21]SETHNA J P,DAHMEN K A,MYERS C R.Crackling noise[J].Nature,2001,410:242-250.
[22]霍润,王强,闫计瑞,等.基于超声波检测的砂岩冻融循环破坏过程[J].沈阳建筑大学学报(自然科学版),2016,32(1):17-24.HUO Run,WANG Qiang,YAN Ji-rui,et al.Study on the failure mechanism of sandstone under freeze-thaw cycles based on the ultrasonic test[J].Journal of Shenyang Jianzhu University(Natural Science),2016,32(1):17-24.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |