为研究酸性环境下砂岩的力学性质以及孔隙结构的变化,对酸液腐蚀后的砂岩进行了单轴压缩试验和孔隙率的计算,探讨了腐蚀时间和酸液浓度对砂岩力学参数和孔隙率的影响。结果表明:酸性溶液对砂岩腐蚀情况显著,浸泡后,砂岩孔隙率增大,电镜扫描图孔隙面积明显增加,且溶液浓度越大,腐蚀时间越长,孔隙体积越大;受酸腐蚀砂岩单轴抗压强度和弹性模量降低显著,试验结束后,pH=1硫酸溶液和pH=3硫酸溶液砂岩单轴抗压强度分别降低31.59%和26.99%,弹性模量分别降低64.46%和62.26%;基于次生孔隙率,构建化学损伤变量,并建立了化学损伤变量同力学参数的关系式;砂岩力学参数的降低与次生孔隙率的变化具有较好的一致性。
Abstract
In the aim of obtaining the changes in mechanical properties and porosity of sandstone in acid environment, we examined the influences of corrosion time and acid concentration on sandstone’s mechanics properties and porosity through uniaxial compression test on acid-corroded sandstone. Results revealed an apparent corrosion effect on sandstone. The porosity of sandstone soaked in acid solution increased, as reflected by an evident expansion of porosity area in SEM images; the volume of porosity is in positive relation with acid concentration and corrosion time. Moreover, the uniaxial compressive strength and elastic modulus of sandstone deteriorated remarkably after acid corrosion. The uniaxial compressive strength of sandstone corroded by pH = 1 sulfuric acid solution and pH = 3 sulfuric acid solution decreased by 31.59% and 26.99%, respectively, and the elastic modulus reduced by 64.46% and 62.26%, respectively. In addition, the relation between chemical damage variable based on secondary porosity and mechanics parameters was established; the deterioration of mechanical parameters of sandstone is consistent with the change of secondary porosity.
关键词
砂岩 /
水岩化学反应 /
孔隙率 /
化学损伤 /
腐蚀机制 /
单轴抗压强度 /
弹性模量
Key words
sandstone /
water-rock chemical reaction /
porosity /
chemical damage /
corrosion mechanism /
uniaxial compressive strength /
elastic modulus
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参考文献
[1] 陈四利,冯夏庭,周 辉.化学腐蚀下砂岩三轴压缩力学效应的试验[J] .东北大学学报, 2003,24(3):292-295.
[2] 陈四利,冯夏庭,周 辉.化学腐蚀下砂岩三轴细观损伤机理及损伤变量分析[J] .岩土力学, 2004,25(9):1363-1367.
[3] 陈四利,冯夏庭,李邵军.岩石单轴抗压强度与破裂特征的化学腐蚀效应[J] .岩石力学与工程学报, 2003,22(4):547-551.
[4] 陈四利,冯夏庭,李邵军.化学腐蚀下三峡花岗岩的破裂特征[J] .岩土力学, 2003,24(5):817-821.
[5] FENG X T, CHEN S L, LI S J. Effects of Water Chemistry on Microcracking and Compressive Strength of Granite[J] . International Journal of Rock Mechanics and Mining Sciences, 2001, 38(4):557-568.
[6] FENG X T, LI S J, CHEN S L. Effect of Water Chemical Corrosion on Strength and Cracking Characteristics of Rock-A Review[J] . Key Engineering Materials, 2004,261(2):1355-1360.
[7] 冯夏庭,丁梧秀.应力-水流-化学耦合下砂岩破裂全过程的细观力学试验[J] .岩石力学与工程学报, 2005,24(9):1465-1473.
[8] 霍润科.酸性环境下砂浆、砂岩材料的受酸腐蚀过程及其基本特性劣化规律的试验研究[D] .西安:西安理工大学, 2006.
[9] 霍润科.酸性环境下岩石及混凝土的耐久性分析[J] .西安建筑科技大学学报, 2007,39(5): 657-660.
[10] 姚华彦.化学溶液及其水压下灰岩破裂过程宏细观力学试验与理论分析[D] .武汉:中国科学院武汉岩土力学研究所, 2008.
[11] 姚华彦,冯夏庭,崔 强.化学侵蚀下硬脆性灰岩变形和强度特性的试验研[J] .岩土力学, 2009,30(2):338-344.
[12] 李 鹏,刘 建,李国和.水化学作用对砂岩抗剪强度特性影响效应研究[J] .岩土力学, 2011,32(2): 380-386.
[13] 许 江,吴 慧,程立朝,等.酸性条件下砂岩剪切破坏特性试验研究[J] .岩石力学与工程学报, 2012, 31(增刊 2): 3898-3903.
[14] 陈有亮,王 朋,张学伟,等.花岗岩在化学溶蚀和冻融循环后的力学性能试验研究[J] .岩土工程学报,2014,36(12): 2227-2235.
[15] 丁梧秀,徐 桃,王鸿毅,等.水化学溶液及冻融耦合作用下灰岩力学特性试验研究[J] .岩石力学与工程学报,2015, 34(5): 979-985.
[16] 牛传星,秦 哲,冯佰研,等.水岩作用下蚀变岩力学性质损伤规律[J] .长江科学院院报, 2016,33(2):75-79.
[17] 闻 名,陈 震,许金余,等.不同含水率红砂岩静动态劈拉试验及细观分析[J] .地下空间与工程学报,2017,13(1):86-92.
[18] 王 伟,李雪浩,朱其志,等.水化学腐蚀对砂板岩力学性能影响的试验研究[J] .岩土力学,2017,38(9):2559-2573.
基金
国家自然科学基金项目(41172237);陕西省教育厅专项基金项目(11JK0947)
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