化学腐蚀和干湿循环作用下砂岩Ⅰ型断裂韧度及其强度参数相关性的研究
|
摘要
以三峡库区典型的库岸边坡消落带节理砂岩体的实际赋存环境为背景,采用在砂岩中预制Ⅰ型裂隙的方法来模拟节理岩体,根据工程实际设计饱水-风干循环试验方案,研究了浸泡在不同化学溶液中的Ⅰ型裂纹砂岩在干湿循环作用下的力学特性及损伤劣化机理,分析了经不同化学溶液和干湿循环作用后试样的物理力学特性随干湿循环次数的劣化规律。研究结果表明:化学溶液和干湿循环作用后砂岩试样呈现出明显的弱化趋势;试验初期,强碱性溶液下砂岩试样的干湿劣化程度最小,但随着干湿循环次数的增加,强碱性溶液下砂岩试样的干湿劣化程度逐渐加剧,仍小于酸性溶液下的,但大于中性溶液下的。化学干湿循环作用后,砂岩试样各力学特征的损伤劣化程度存在明显的差异,其中断裂韧度KIC的劣化程度较大,抗拉强度居中,而抗压强度最小。化学干湿循环作用后砂岩的断裂韧度与抗压强度、抗拉强度间存在明显的线性关系。砂岩各力学特征的劣化程度与其相应的化学溶液中溶出离子浓度的大小、试样物理参数的劣化程度之间具有某一对应关系,同时,得到砂岩试样物理力学参数与损伤变量和钙镁离子浓度之间统计上的关联关系。并且,可以利用不同化学溶液和干湿循环作用下砂岩试样的裂纹扩展半径来间接说明其力学特征发生损伤的劣化程度。
Taking the actual environment of the hydro-fluctuation belt of a typical bank slope in the Three Gorges Reservoir Region as background,by means of prefabricating mode-Ⅰ cracks in the sandstone speci-mens,one test scheme of drying-wetting cycles is adopted to explore the mechanical characteristics anddamage degradation mechanism of mode-Ⅰ sandstone specimens immersed in different chemical solutions.The variation regularities in the physical and mechanical prosperities were analyzed under the effects ofchemical solutions and drying-wetting cycles. Experimental results show that sandstone specimens have a sig-nificant damage deteriorating trend under effect of chemical solutions and drying-wetting cycles. In the first0~1 drying-wetting cycles, the degradation degree of sandstone specimens immersed in alkaline Na_2 SO_4(pH=12.0) solutions is the smallest,however,its damage degree in Na_2 SO_4(pH=12.0) solutions graduallyincreased with the increasing of F-T cycles,but it is still less than that in the acid Na_2 SO_4(pH=3.0) solu-tion and was greater than that in neutral Na_2 SO_4(p H=7.0) solutions. There is a difference in the damagedeterioration degree of mechanical properties under effect of chemical solution and drying-wetting cycles,that is, the damage deterioration degree of fracture toughness KIC is the greatest, that of compressionstrength is the smallest. Meanwhile,there are obvious linear relationship among fracture toughness KIC,com-pression strength and tensile strength under the effects of different chemical solutions and drying-wetting cy-cles. Meanwhile, there are also obvious consistency relationship among the damage degree of mechanicalproprieties,its damage degree of physical proprieties and the ions concentration dissolved in the correspond-ing chemical solution. Therefore,the correlation relationships among physical and mechanical proprieties ofsandstone,damage variables and the ions concentration of calcium and magnesium are obtained. The crackpropagation radius can be used to indicate the damage deterioration degree of mechanical proprieties under chemical solutions and drying-wetting cycles.
Taking the actual environment of the hydro-fluctuation belt of a typical bank slope in the Three Gorges Reservoir Region as background,by means of prefabricating mode-Ⅰ cracks in the sandstone speci-mens,one test scheme of drying-wetting cycles is adopted to explore the mechanical characteristics anddamage degradation mechanism of mode-Ⅰ sandstone specimens immersed in different chemical solutions.The variation regularities in the physical and mechanical prosperities were analyzed under the effects ofchemical solutions and drying-wetting cycles. Experimental results show that sandstone specimens have a sig-nificant damage deteriorating trend under effect of chemical solutions and drying-wetting cycles. In the first0~1 drying-wetting cycles, the degradation degree of sandstone specimens immersed in alkaline Na_2 SO_4(pH=12.0) solutions is the smallest,however,its damage degree in Na_2 SO_4(pH=12.0) solutions graduallyincreased with the increasing of F-T cycles,but it is still less than that in the acid Na_2 SO_4(pH=3.0) solu-tion and was greater than that in neutral Na_2 SO_4(p H=7.0) solutions. There is a difference in the damagedeterioration degree of mechanical properties under effect of chemical solution and drying-wetting cycles,that is, the damage deterioration degree of fracture toughness KIC is the greatest, that of compressionstrength is the smallest. Meanwhile,there are obvious linear relationship among fracture toughness KIC,com-pression strength and tensile strength under the effects of different chemical solutions and drying-wetting cy-cles. Meanwhile, there are also obvious consistency relationship among the damage degree of mechanicalproprieties,its damage degree of physical proprieties and the ions concentration dissolved in the correspond-ing chemical solution. Therefore,the correlation relationships among physical and mechanical proprieties ofsandstone,damage variables and the ions concentration of calcium and magnesium are obtained. The crackpropagation radius can be used to indicate the damage deterioration degree of mechanical proprieties under chemical solutions and drying-wetting cycles.
引文
[1] HEGGHEIM T,MADLAND M V,et al. A chemical induced enhanced weakening of chalk by seawater[J]. Jour-nal of Petroleum Science and Engineering,2005,46:171-184.
[2] CHEN Y,CAO P,CHEN R. Effect of water-rock interaction on the morphology of a rock surface[J]. Internation-al Journal of Rock Mechanics and Mining Sciences,2010,47(5):816-822.
[3] WU X D. Experimental study on the time-dependent behaviour of Xiangjiaba Sandstone[J]. Applied Mechanicsand Materials,2013,256/259:174-178.
[4] NEGREL P,MILLOT R,ROY S,et al. Lead isotopes in groundwater as an indicator of water-rock interaction(Masheshwaram catchment,Andhra Pradesh,India)[J]. Chemical Geology,2010,274(3):136-148.
[5] FENG X T,CHEN S L,LI S J. Effects of water chemistry on micro cracking and compressive strength of granite[J]. International Journal of Rock Mechanics and Mining Sciences,2001,38(4):557-568.
[6] LI N,ZHU Y M,BO S,et al. A chemical damage model of sandstone in acid solution[J]. International Journalof Rock Mechanics and Mining Sciences,2003,40(2):243-249.
[7] BACKSTROM A,ANTIKAINEN J,BACKERS T,et al. Numerical modelling of uniaxial compressive failure ofgranite with and without saline porewater[J]. International Journal of Rock Mechanics and Mining Sciences,2008,45(7):1126-1142.
[8] FENG X T,DING W X,ZHANG D X. Multi-crack interaction in limestone subject to stress and flow of chemicalsolutions[J]. International Journal of Rock Mechanics and Mining Sciences,2009,46(1):159-171.
[9] YOSHITAKA N,KAZUYA M,NAOKI H,et al. Influence of relative humidity on fracture toughness of rock:Im-plications for subcritical crack growth[J]. International Journal of Solids and Structures,2012,49:2471-2481.
[10] REINHARDT H W,MIELICH O. Fracture toughness of alkali-sensitive rocks in alkaline solution[J]. Interna-tional Journal of Rock Mechanics and Mining Sciences,2014,70:552-558.
[11]韩铁林,师俊平,陈蕴生.砂岩在化学腐蚀和冻融循环共同作用下力学特征劣化的试验研究[J].水利学报,2016,47(5):644-655.
[12]刘杰,李建林,屈建军,等.宜昌砂岩轴压致裂和人工裂纹下的渗流试验研究[J].水利学报,2010,41(12):1461-1468.
[13] HALE P A,SHAKOOR A. A laboratory investigation of the effects of cyclic heating and cooling,wetting and dry-ing,and freezing and thawing on the compressive strength of selected sandstones[J]. Environmental and Engi-neering Geoscience,2003,9(2):117-130.
[14] LIN M L,JENG F S,TSAI L S,et al. Wetting weakening of tertiary sandstones-microscopic mechanism[J]. Environment Geology,2005,48:265-275.
[15] JENG F S,LIN M L,HUANG T H. Wetting deterioration of soft sandstone-microscopic insights[C]//An Interna-tional Conference on Geotechnical and Geological Engineering. Melbourne,2000.
[16]黄维辉.干湿交替作用下砂岩劣化效应研究[D].昆明:昆明理工大学,2014.
[17]姚华彦,朱大勇,周雨新,等.干湿交替作用后砂岩破裂过程实时观测与分析[J].岩土力学,2013,34(2):328-336.
[18]王伟,龚传根,朱鹏辉,等.大理岩干湿循环力学特性试验研究[J].水利学报,2017,48(10):1175-1184.
[19]金伟良,金立兵,延永东,等.海水干湿交替区氯离子对混凝土侵入作用的现场检测和分析[J].水利学报,2009,40(3):364-371.
[20]郭进军,杨梦,陈红莉,等.干湿循环下改性混凝土硫酸盐腐蚀的断裂性能试验研究[J].水利学报,2018,49(4):419-427.
[21]张廷毅,汪自力,郑光和,等.碳化与硫酸盐溶液干湿循环后混凝土断裂韧度[J].水利学报,2016,47(8):1062-1069.
[22]中华人民共和国行业标准编写组. DL/T 5368-2007水电水利工程岩石试验规程[S].北京:中国水利水电出版社,2007.
[23]韩铁林,师俊平,陈蕴生.干湿循环和化学腐蚀共同作用下单裂隙非贯通试样力学特征的试验研究[J].水利学报,2016,47(12):1566-1576.
[24]韩铁林,师俊平,陈蕴生,等.化学侵蚀后砂岩力学特性的劣化及其细观结构损伤定量化方法[J].材料研究学报,2015,29(12):921-930.
[25]邓华锋,李建林,孙旭曙,等.水作用下砂岩断裂力学效应试验研究[J].岩石力学与工程学报,2012,31(7):1342-1348.
[2] CHEN Y,CAO P,CHEN R. Effect of water-rock interaction on the morphology of a rock surface[J]. Internation-al Journal of Rock Mechanics and Mining Sciences,2010,47(5):816-822.
[3] WU X D. Experimental study on the time-dependent behaviour of Xiangjiaba Sandstone[J]. Applied Mechanicsand Materials,2013,256/259:174-178.
[4] NEGREL P,MILLOT R,ROY S,et al. Lead isotopes in groundwater as an indicator of water-rock interaction(Masheshwaram catchment,Andhra Pradesh,India)[J]. Chemical Geology,2010,274(3):136-148.
[5] FENG X T,CHEN S L,LI S J. Effects of water chemistry on micro cracking and compressive strength of granite[J]. International Journal of Rock Mechanics and Mining Sciences,2001,38(4):557-568.
[6] LI N,ZHU Y M,BO S,et al. A chemical damage model of sandstone in acid solution[J]. International Journalof Rock Mechanics and Mining Sciences,2003,40(2):243-249.
[7] BACKSTROM A,ANTIKAINEN J,BACKERS T,et al. Numerical modelling of uniaxial compressive failure ofgranite with and without saline porewater[J]. International Journal of Rock Mechanics and Mining Sciences,2008,45(7):1126-1142.
[8] FENG X T,DING W X,ZHANG D X. Multi-crack interaction in limestone subject to stress and flow of chemicalsolutions[J]. International Journal of Rock Mechanics and Mining Sciences,2009,46(1):159-171.
[9] YOSHITAKA N,KAZUYA M,NAOKI H,et al. Influence of relative humidity on fracture toughness of rock:Im-plications for subcritical crack growth[J]. International Journal of Solids and Structures,2012,49:2471-2481.
[10] REINHARDT H W,MIELICH O. Fracture toughness of alkali-sensitive rocks in alkaline solution[J]. Interna-tional Journal of Rock Mechanics and Mining Sciences,2014,70:552-558.
[11]韩铁林,师俊平,陈蕴生.砂岩在化学腐蚀和冻融循环共同作用下力学特征劣化的试验研究[J].水利学报,2016,47(5):644-655.
[12]刘杰,李建林,屈建军,等.宜昌砂岩轴压致裂和人工裂纹下的渗流试验研究[J].水利学报,2010,41(12):1461-1468.
[13] HALE P A,SHAKOOR A. A laboratory investigation of the effects of cyclic heating and cooling,wetting and dry-ing,and freezing and thawing on the compressive strength of selected sandstones[J]. Environmental and Engi-neering Geoscience,2003,9(2):117-130.
[14] LIN M L,JENG F S,TSAI L S,et al. Wetting weakening of tertiary sandstones-microscopic mechanism[J]. Environment Geology,2005,48:265-275.
[15] JENG F S,LIN M L,HUANG T H. Wetting deterioration of soft sandstone-microscopic insights[C]//An Interna-tional Conference on Geotechnical and Geological Engineering. Melbourne,2000.
[16]黄维辉.干湿交替作用下砂岩劣化效应研究[D].昆明:昆明理工大学,2014.
[17]姚华彦,朱大勇,周雨新,等.干湿交替作用后砂岩破裂过程实时观测与分析[J].岩土力学,2013,34(2):328-336.
[18]王伟,龚传根,朱鹏辉,等.大理岩干湿循环力学特性试验研究[J].水利学报,2017,48(10):1175-1184.
[19]金伟良,金立兵,延永东,等.海水干湿交替区氯离子对混凝土侵入作用的现场检测和分析[J].水利学报,2009,40(3):364-371.
[20]郭进军,杨梦,陈红莉,等.干湿循环下改性混凝土硫酸盐腐蚀的断裂性能试验研究[J].水利学报,2018,49(4):419-427.
[21]张廷毅,汪自力,郑光和,等.碳化与硫酸盐溶液干湿循环后混凝土断裂韧度[J].水利学报,2016,47(8):1062-1069.
[22]中华人民共和国行业标准编写组. DL/T 5368-2007水电水利工程岩石试验规程[S].北京:中国水利水电出版社,2007.
[23]韩铁林,师俊平,陈蕴生.干湿循环和化学腐蚀共同作用下单裂隙非贯通试样力学特征的试验研究[J].水利学报,2016,47(12):1566-1576.
[24]韩铁林,师俊平,陈蕴生,等.化学侵蚀后砂岩力学特性的劣化及其细观结构损伤定量化方法[J].材料研究学报,2015,29(12):921-930.
[25]邓华锋,李建林,孙旭曙,等.水作用下砂岩断裂力学效应试验研究[J].岩石力学与工程学报,2012,31(7):1342-1348.