Experimental study on mechanical properties and damage degradation mechanism of calcareous sandstone subjected to freeze-thaw cycles
HAN Tie-lin1, 2, CHEN Yun-sheng1, 2, SHI Jun-ping1, LI Zhi-hui1
1. School of Civil Engineering and Architecture, Xi'an University of Technology, Xi'an 710048, China; 2. Institute of Geotechnical Engineering, Xi'an University of Technology, Xi'an 710048, China
Abstract:The damage degradation mechanism and physical and mechanical properties of sandstone under the coupling effect of chemical solution and freeze-thaw cycles are studied through laboratory tests. The sandstone specimens soaked in different chemical solutions are studied by freeze-thaw cycle tests. The physical and mechanical properties of sandstone specimens due to different freeze-thaw cycles are measured at the same time. The results show that the damage deterioration mode of sandstone specimens is different under the coupling effect of chemical solution and freeze-thaw cycles. There are two main modes of sandstone deterioration, i.e., the grain spalling and scaling mode, and the fracturing mode. The damage degradation degree of the physical and mechanical characteristics of sandstone due to freeze-thaw cycles is the largest in strong acidic conditions (pH = 3.0), and that in strong alkaline environment(pH=12.0)comes the second, that is, it has a certain degree of mitigation in the neutral to weakly alkaline environment, but the degradation still increases with the increase of cycling times continuously. The greater the concentration of Na2SO4 solution, the larger the reduction rate of freeze-thaw coefficient. The damage degradation degree of sandstone subjected to freeze-thaw cycles is the largest in 0.01 mol/L Na2SO4 pH=9.0 than that in 0.01 mol/L NaHCO3 pH=9.0. The freeze-thaw damage of sandstone is closely related to water chemical environment. The chemical solutions have certain chemical etching effect on sandstone, and the coupling effect together with freeze-thaw cycles can give mutual effect on the degradation and damage of sandstone.
韩铁林,陈蕴生,师俊平,李智慧. 冻融循环下钙质砂岩力学特性及其损伤劣化机制的试验研究[J]. 岩土工程学报, 2016, 38(10): 1802-1812.
HAN Tie-lin, CHEN Yun-sheng, SHI Jun-ping, LI Zhi-hui. Experimental study on mechanical properties and damage degradation mechanism of calcareous sandstone subjected to freeze-thaw cycles. Chinese J. Geot. Eng., 2016, 38(10): 1802-1812.
[1] KOSTROMITINOV, NIKOLENKO K N, NIKITIN S D. Testing the strength of frozen rocks on samples of various forms (In Russian). Increasing the effectiveness of mining industry in Yakutia[J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1974, 12(2): 32-37. [2] MCGREEVY J P. Rock moisture content and frost weathering under natural and experimental conditions:a comparative discussion[J]. Arctic and Alpine Research, 1985, 17(3): 337-346. [3] HALL B. The breakdown of rock due to freezing:a theoretical mode[C]// Proceeding of the 4th International Conference on Permafrost. Washington D C, 1983. [4] NICHOLSON H, DAWN T, NICHOLSON F. Physical deterioration of sedimentary rocks subjected to experimental freezing thawing weathering[J]. Earth Surface Processes and Landforms, 2000, 25(12): 1295-1308. [5] MUTLUTÜRK M, ALTINDAG R, TÜRK G. A decay function model for the integrity loss of rock when subjected to recurrent cycles of freezing-thawing and heating cooling[J]. International Journal of Rock Mechanics & Mining Sciences, 2004, 41: 237-244. [6] TAN X J, CHEN W Z, YANG J P, et al. Laboratory investigations on the mechanical properties degradation of granite under freeze-thaw cycles[J]. Cold Regions Science and Technology, 2011, 68: 130-138. [7] 方 云, 乔 梁, 陈 星, 等. 云冈石窟砂岩循环冻融试验研究[J]. 岩土力学, 2014, 35(9): 2433-2442. (FANG Yun, QIAO Liang, CHEN Xing, et al. Experimental study of freezing-thawing cycles on sandstone in Yungang grottos[J]. Rock and Soil Mechanics, 2014, 35(9): 2433-2442. (in Chinese)) [8] 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): 2226-2235. (CHEN You-liang, WANG Peng,ZHANG Xuewei, et al. Experimental research on mechanical properties of granite in chemical dissolution under freeze-thaw cycles[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(12): 2226-2235. (in Chinese)) [9] 苏 伟. 冻融循环对岩石物理力学性质及边坡稳定性影响的研究[D]. 长沙: 长沙矿山研究院, 2012. (SU Wei. Study on physical and mechanical properties of rocks and slope stability under freeze-thaw cycle[D]. Changsha: Changsha Institute of Mining Research, 2012. (in Chinese)) [10] 俞 缙, 傅国锋, 陈 旭, 等. 冻融循环作用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 sandstone after freezing-thawing cycles under triaxial confining pressure unloading[J]. Chinese Journal of rock mechanics and Engineering, 2015, 34(10): 2001-2009. (in Chinese)) [11] ALTINDAG R, ALYILDIZ I S, ONARGAN T. Mechanical property degradation of ignimbrite subjected to recurrent freeze-thaw cycles[J]. International Journal of Rock Mechanics & Mining Sciences, 2004, 41: 1023-1028. [12] TAN Xian-jun, CHEN Wei-zhong, YANG Jian-ping, et al. Laboratory investigations on the mechanical properties degradation of granite under freeze-thaw cycles[J]. Cold Regions Science and Technology, 2011, 68(3): 130-138. [13] PAKR C, SYNN J H, SHIN D S. Experimental study on the thermal characteristics of rock at low temperatures[J]. International Journal of Rock Mechanics & Mining Science, 2004, 41(S1): 81-86. [14] 李新平, 路亚妮, 王仰君. 冻融荷载耦合作用下单裂隙岩体损伤模型研究[J]. 岩石力学与工程学报, 2013, 32(11): 2307-2315. (LI Xin-ping, LU Ya-ni, WENG Yang-jun. Research on damage model of single jointed rock masses under coupling action of freeze-thaw and loading[J]. Chinese Journal of rock mechanics and Engineering, 2013, 32(11): 2307-2315. (in Chinese)) [15] 刘 华, 牛富俊, 徐志英, 等. 循环冻融条件下安山岩和花岗岩的物理力学特性试验研究[J]. 冰川冻土, 2011, 33(3): 557-563. (LIU Hua, NIU Fu-jun, XU Zhi-ying, et al. Acoustic experimental study of two of rock from the Tibetan Plateau under the condition of freeze-cycles[J]. Journal of Claciology and Ceocryology, 2011, 33(3): 557-563. (in Chinese)) [16] FENER M, INCE I. Effects of the freeze-thaw (F-T) cycle on the andesitic rocks (Sille-Kony/Turkey) used in construction building[J]. Journal of African Earth Sciences, 2015, 109: 96-106.