High-temperature influence on mechanical properties ofdiorite
High-temperature influence on mechanical properties ofdiorite
复制标题
高温对闪长岩力学性能的影响
DOI：
10.1007/s00603-017-1185-3
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发表时间：
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影响因子：
6.2
通讯作者：
Yan Qin
中科院分区：
文献类型：
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作者：
Tian Hong;Gang Mei;Guo-Sheng Jiang;Yan Qin
了解高温条件下/高温后岩石力学行为对核废料深层地质处置（Sellin and Leupin 2013; Verma et al. 2015）、热干岩（HDR）地热能开采（Brown et al. 2012; Gelet et al. 2012）和地下煤气化（Burton et al. 2006; Otto and Kempka 2015）等项目至关重要，可以为项目的变形、稳定性和安全性分析提供依据。高温会引起造岩矿物的热膨胀、热应力和岩体内的化学反应，从而产生微裂纹，破坏岩石微观结构。因此，岩石在高温条件下的行为可能与常温条件下的行为大不相同。已知岩石强度和变形模量一般随温度升高而降低，特别是超过一定温度后（如Dwivedi et al. 2008; Chen et al. 2012; Singh et al. 2015; Tian et al. 2016; Peng et al. 2016; Ding et al. 2016）。因此，对高温岩石力学的研究具有重要的理论意义和实践意义。花岗岩和闪长岩等花岗质岩石是广泛接受的核废料处置场所，也是HDR储层的主要岩石类型。到目前为止，已经进行了大量的实验研究，对花岗岩在高达1000℃高温下的力学性能进行了研究。Dwivedi等（2008）通过实验和文献综述得出，花岗岩的变形模量、抗拉强度和抗压强度基本随温度的升高而降低。Singh等人（2015）基于应变率为0.05和0.5 mm/min的实时高温单轴压缩测试系统，发现花岗岩的单轴抗压强度（UCS）和弹性模量(E)在200℃以上随温度降低，而Homand-etienne和Houpert（1989）、Chen等人（2012）和Liu和Xu（2014）发现阈值温度为400℃。但在高温处理后的花岗岩试样上进行了测试，结果表明，在400℃以后，随温度的升高而急剧降低。Shao et al.（2015）和Yin et al.（2016）观测到花岗岩的UCS和E随温度升高而降低，温度可达1000℃，闪长岩储量在某些地区可能比花岗岩储量大得多，可以替代花岗岩作为核废料地质处置的寄主岩。它也是一种干热岩石。然而，目前有关闪长岩在高温下的力学行为的研究资料有限。为了进一步了解高温对闪长岩力学性能的影响，我们对闪长岩样品进行了一系列的单轴压缩试验，并将其热处理至1000℃。
Knowledge on rock mechanical behaviors under/after hightemperature conditions is extremely important for projects such as deep geological disposal of nuclear waste (Sellin and Leupin 2013; Verma et al. 2015), hot dry rock (HDR) geothermal energy extraction (Brown et al. 2012; Gelet et al. 2012), and underground coal gasification (Burton et al. 2006; Otto and Kempka 2015), for it can provide a basis for deformation, stability, and safety analyses of the projects. High temperatures can cause thermal expansion of rock-forming minerals, thermal stresses, and chemical reactions in a rock body and thus produces micro-cracks and damages rock microstructures. As a result, rock behaviors exposed to high temperatures may be quite different from those under normal temperature conditions. It has been known that rock strength and deformation modulus generally decrease with increasing temperature, especially beyond a certain temperature (eg, Dwivedi et al. 2008; Chen et al. 2012; Singh et al. 2015; Tian et al. 2016; Peng et al. 2016; Ding et al. 2016). Therefore, research on high-temperature rock mechanics is important and essential in both theory and practice. Granitic rocks such as granite and diorite are a widely acceptable site for nuclear waste disposal and are also main rock types of HDR reservoir. Up to now, a large amount of experimental research has been performed to investigate the mechanical properties of granite exposed to high temperatures up to 1000 C. Dwivedi et al.(2008) presented deformation modulus, tensile, and compressive strength of granites basically decrease with temperature according to their experiments and literature review. Based on a real-time high-temperature uniaxial compression testing system with strain rates of 0.05 and 0.5 mm/min, Singh et al.(2015) found uniaxial compression strength (UCS) and elastic modulus (E) of granite decrease with temperature from 200 C onward, while Homand-etienne and Houpert (1989), Chen et al.(2012) and Liu and Xu (2014) discovered the threshold temperature is 400 C. They found granite UCS changes slightly from room temperature to 400 C, but dramatically decreases with temperature from 400 C onward, by means of testing on granite sample after high-temperature treatment. Shao et al.(2015) and Yin et al.(2016) observed UCS and E of granites decrease with temperature up to 1000 C.Diorite reserves may be much larger than that of granite in some areas and can be a substitute for granite as the host rock of nuclear waste geological disposal. It is also one type of hot dry rocks. However, limited reference related to the mechanical behavior of diorite exposed to high temperatures is available now. To extend our knowledge on high-temperature influences on mechanical properties of diorite, a series of uniaxial compression tests were performed on diorite samples after thermal treatment up to 1000 C.