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Gold Science and Technology >

2021 , Vol. 29 >Issue 6: 834 - 842

DOI: https://doi.org/10.11872/j.issn.1005-2518.2021.06.104

Mining Technology and Mine Management

Study on Mode Ⅰ and Mode Ⅱ Fracture Characteristics of Granite Under Different Thermal Shock Process

  • Xiaodong FAN , 1 ,
  • Xiang LI , 1, 2 ,
  • Ming TAO 1 ,
  • Tubing YIN 1 ,
  • Xibing LI 1
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  • 1. School of Resources and Safety Engineering, Central South University, Changsha 410083, Hunan, China
  • 2. School of Civil Engineering, Sun Yat-sen University, Zhuhai 519082, Guangdong, China

Received date: 2021-07-28

  Revised date: 2021-10-03

  Online published: 2022-03-07

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Highlights

In the high temperature related disasters occurring in rock engineering，the effect of rapid cooling （thermal shock） can’t be ignored.Therefore，the study on mode Ⅰ and mode Ⅱ fracture toughness of granite under different degrees of thermal shock can provide theoretical basis and technical support for the stability analysis of rock engineering after thermal shock disasters.In this experiment，the granite is heated to the target temperature （200 ℃，400 ℃，600 ℃）.According to the characteristics of low freezing point of calcium chloride solution，calcium chloride solution is used as refrigerant，and refrigerants of -20 ℃，20 ℃ and 60 ℃ are obtained by means of freezing and heating respectively，and thermocouple thermometer is used to ensure that the temperature of refrigerating liquid reached the set temperature.Use refrigerants （-20 ℃，20 ℃，60 ℃） for three different cooling rate of the high temperature granite processing，namely the three different levels of thermal shock.The physical properties of the samples are measured before and after heat treatment，including dry density，porosity and P wave velocity.In the end，mode Ⅰ and mode Ⅱ fracture toughness of specimens is tested by Brazilian splitting test.The experimental results show that the dry density and P-wave velocity of heated granite samples decrease with the increase of cooling rate，while the porosity increases with the increase of cooling rate.These phenomena are related to the opening and expansion of pores and micro-cracks caused by thermal shock，that is，more violent thermal shock will cause more serious damage to granite.In addition，with the increase of heating temperature，the sensitivity of the physical properties of heated granite to the temperature change of refrigeration liquid decreases during the cooling process.In terms of fracture toughness，the fracture toughness of granite as a whole decreases significantly with the increase of heating temperature.In addition，at the same high temperature level，the mode Ⅰ and mode Ⅱ fracture toughness of heated granite decreases linearly with the decrease of cooling liquid temperature，which is roughly the same as the change trend of physical properties of granite.The main causes of thermal shock damage are the non-uniform expansion and contraction of minerals inside the rock and the disharmony of deformation caused by the temperature gradient inside and outside the rock.The tensile stress generated by the temperature gradient inside and outside the rock is positively correlated with the temperature difference between granite and refrigerant.

Cite this article

Xiaodong FAN , Xiang LI , Ming TAO , Tubing YIN , Xibing LI . Study on Mode Ⅰ and Mode Ⅱ Fracture Characteristics of Granite Under Different Thermal Shock Process[J]. Gold Science and Technology, 2021 , 29(6) : 834 -842 . DOI: 10.11872/j.issn.1005-2518.2021.06.104

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巴西制定矿业发展规划2050

据BNAmericas网站报道，巴西政府已经启动2050年矿业规划系列研究，为矿业发展提供指南。本周，巴西能矿部矿冶司联合国家行政管理学院（ENAP， National School of Public Administration）举行首次工作会，听取有关方面对2050年全国矿业规划（PNM）的意见。

“该规划将确立巴西矿业2022—2050年发展的指导方针和长期目标，指明方向并提出解决方案，该规划将取代2011年发布的PNM2030”，能矿部在一份新闻稿中表示。

私营企业的一个需求是希望政府制定实现矿业多元化的战略，摆脱目前对铁矿石的过度依赖。“我们需要长期吸引投资开发更多矿业项目，包括铜、镍、锂和钴生产的政策和战略，满足清洁能源发展需求”巴西矿业公司协会会长米格尔·内里（Miguel Nery）表示。

不过，相关方面警告，巴西矿业长期规划也需要制定环境方面的措施，因为全世界的投资者对这方面的担忧与日俱增。“矿业项目一半需要有效的监管机制，要确定矿产品是否采自保护区。没有这些措施，未来项目不可能获得资金”，可持续发展非政府组织埃斯科利亚斯研究所（Instituto Escolhas）项目经理拉里萨·罗德里格斯（Larissa Rodrigues）表示。

http://www.goldsci.ac.cn/article/2021/1005-2518/1005-2518-2021-29-6-834.shtml

References

Publishing order | Descend order by publishing year | Descend order by cited within
Atkinson C， Smelser R E， Sanchez J，1982.Combined mode fracture via the cracked Brazilian disk test［J］.International Journal of Fracture，18（4）：279-291.

Brotóns V， Tomás R， Ivorra S， al et，2013.Temperature influence on the physical and mechanical properties of a porous rock：San Julian’s calcarenite［J］.Engineering Geology，167：117-127.

Cheng Zepeng， Xi Baoping， Yang Xinxin， al et，2021.Experimental study on the evolution of granite permeability under thermal shock［J］. Journal of Taiyuan University of Technology，52（2）：198-203.

Collin M， Rowcliffe D，2000.Analysis and prediction of thermal shock in brittle materials［J］.Acta Materialia，48（8）：1655-1665.

Fowell R，1995.Suggested method for determining mode I fracture toughness using Cracked Chevron Notched Brazilian Disc（CCNBD）specimens［J］.International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abs-tracts，32（1）：57-64.

Franklin J， Vogler U， Szlavin J， al et，1979.Suggested methods for determining water content，porosity，density，absorption and related properties and swelling and slake-durability index properties： Part 1： Suggested methods for determining water content，porosity，density，absorption and related properties［J］.International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts，16（2）：143-151.

Hall K， Thorn C E，2014.Thermal fatigue and thermal shock in bedrock： An attempt to unravel the geomorphic processes and products［J］.Geomorphology，206：1-13.

He Manchao，2010.The Basis of Deep Rock Mechanics［M］.Beijing：Science Press.

He Manchao， Xie Heping， Peng Suping， al et，2005.Study on rock mechanics in deep mining engineering［J］.Chinese Jo-urnal of Rock Mechanics and Engineering，（16）：2803-2813.

Huang Zhenping， Zhang Yi， Wu Weida，2016.Analysis of mechanical and wave properties of heat-treated marble by water cooling［J］.Rock and Soil Mechanics，37（2）：367-375.

Kingery W D，1955.Factors affecting thermal stress sesistance of ceramic materials［J］. Journal of the American Ceramic Society，38（1）：3-15.

Kuruppu M D， Obara Y， Ayatollahi M R， al et，2014.ISRM-Suggested method for determining the mode I static fracture toughness using semi-circular bend specimen［J］.Rock Me-chanics and Rock Engineering，47（1）：267-274.

Li Q， Yin T， Li X， al et，2020.Effects of rapid cooling treatment on heated sandstone：A comparison between water and liquid nitrogen cooling［J］. Bulletin of Engineering Geology and the Environment，79（1）：313-327.

Li X， Li B， Li X， al et，2020.Thermal shock effects on the mechanical behavior of granite exposed to dynamic loading ［J］.Archives of Civil and Mechanical Engineering，20（3）.DOI： 10.1007/s43452-020-00070-w .

Li X， Zhang Z， Chen W， al et，2019.Mode I and mode II granite fractures after distinct thermal shock treatments［J］.Journal of Materials in Civil Engineering，31（4）：6019001.

Liu H， Zhang K， Shao S， al et，2020.Numerical investigation on the cooling-related mechanical properties of heated Australian Strathbogie granite using Discrete Element Method［J］.Engineering Geology，264：105371.

Shen Y， Hou X， Yuan J， al et，2019.Experimental study on temperature change and crack expansion of high temperature granite under different cooling shock treatments［J］.Energies，12（11）：2097.

Tang Shibin， Luo Jiang， Tang Chun’an，2018.Theoretical and numerical study on the cryogenic fracturing in rock［J］.Chinese Journal of Rock Mechanics and Engineering，37（7）：1596-1607.

Wang Jun， Zhao Lei， Qi Jianghao，2016.Experimental studies on the critical velocity for tunnel fire smoke control under blocked and block-free conditions［J］.Journal of Safety and Environment，16（3）：62-68.

Wu X， Huang Z， Zhang S， al et，2019.Damage analysis of high-temperature rocks subjected to LN2 thermal shock［J］.Ro-ck Mechanics and Rock Engineering，52（8）：2585-2603.

Xie Heping，2017.Research framework and anticipated results of deep rock mechanics and mining theory［J］.Engineering Science and Technology，49（2）：1-16.

Xie Heping， Gao Feng， Ju Yang，2015.Research and development of rock mechanics in deep ground engineering［J］.Chinese Journal of Rock Mechanics and Engineering，34（11）：2161-2178.

成泽鹏，郤保平，杨欣欣，等，2021.热冲击作用下花岗岩渗透性演变规律试验研究［J］.太原理工大学学报，52（2）：198-203.

何满潮，2010.深部岩体力学基础 ［M］.北京：科学出版社.

何满潮，谢和平，彭苏萍，等，2005.深部开采岩体力学研究［J］.岩石力学与工程学报，（16）：2803-2813.

黄真萍，张义，吴伟达，2016.遇水冷却的高温大理岩力学与波动特性分析［J］.岩土力学，37（2）： 367-375.

唐世斌，罗江，唐春安，2018.低温诱发岩石破裂的理论与数值模拟研究 ［J］.岩石力学与工程学报，37（7）：1596-1607.

王君，赵蕾，齐江浩，2016.阻塞效应下隧道火灾临界风速的模型试验研究［J］.安全与环境学报，16（3）：62-68.

谢和平，2017.“深部岩体力学与开采理论”研究构想与预期成果展望［J］.工程科学与技术，49（2）：1-16.

谢和平，高峰，鞠杨，2015.深部岩体力学研究与探索［J］.岩石力学与工程学报，34（11）：2161-2178.

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