Effect of strain rate on the dynamic compressive mechanical behaviors of rock material subjected to high temperatures

Shi, Liyi; Xu, Jinyu

doi:10.1016/j.mechmat.2014.12.006

Cited by 94 publications

(26 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The combination of all these parameters determines the relationship between mechanical rock properties and temperature, which have been widely investigated (e.g. Hajpál 2002;Zhan and Cai 2007;Zhu et al 2007;Qin et al 2009;Shao et al 2014;Liu and Xu 2015). Exposure of rocks to high temperature results in mineral expansion, thermal reactions and stresses inside the rock body, and thus probably causes significant changes in rock micro-cracks, micro-structure and mineral bonds, which can be indirectly analyzed by changes in porosity, permeability and compressive wave velocity.…”

Section: Discussionmentioning

confidence: 99%

Mechanical Properties of Sandstones Exposed to High Temperature

et al. 2015

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Mechanical Properties of Sandstones Exposed to High Temperature

et al. 2015

View full text Add to dashboard Cite

“…Table 2 shows the elastic modulus of granite specimens at various inclination angles. In this paper, the slope of straight-line section of the stress-strain curve in Figure 5a is taken as its elastic modulus, which corresponds to 40-60% of the peak compression stress [9]. Figure 7 shows the "inclination angles vs elastic modulus" curve.…”

Section: Influence Of Specimen Inclination On Peak Compression Stressmentioning

confidence: 99%

“…In these projects, rock mass frequently experiences temperature in the range of 700-900 • C [5,6]. After such high-temperature treatment, the mechanical properties and fracture behavior of rock masses will dramatically change, which lead to structural instability of underground engineering and then induce major geological disasters [7][8][9][10]. Therefore, it is necessary to study the temperature effect of rock material for thermodynamics engineering and Dai [26] performed a dynamic impact test using a modified Split Hopkinson Pressure Bar (SHPB) system and studied the dynamic mechanical properties and failure characteristic of brittle rocks under combined compression-shear loading.…”

Section: Introductionmentioning

confidence: 99%

Effect of High Temperature and Inclination Angle on Mechanical Properties and Fracture Behavior of Granite at Low Strain Rate

Chen

Mao

2020

Sustainability

View full text Add to dashboard Cite

Comprehensive understanding of the effects of temperature and inclination angle on mechanical properties and fracture modes of rock is essential for the design of rock engineering under complex loads, such as the construction of nuclear waste repository, geothermal energy development and stability assessment of deep pillar. In this paper, a novel inclined uniaxial compression (inclined UCS) test system was introduced to carry out two series of inclined uniaxial compression tests on granite specimens under various inclination angles (0-20 • ) and treated temperatures (25-800 • C) at 5 • inclination. Experimental results revealed that the peak compression stress and elastic modulus gradually decreased, while peak shear stress increased nonlinearly with the increasing inclination angle; the peak compression and shear stress as well as elastic modulus slightly increased from 25 to 200 • C, then gradually decreased onwards with the increasing temperature. The effect of temperature on peak axial strain was the same as that on peak shear displacement. Acoustic emission (AE) results suggested that the relationship between crack initiation stress, inclination angle and treated temperature followed a similar trend as that of the peak compression stress and elastic modulus. Particularly, the crack initiation (CI) stress threshold and shear stress corresponding to CI threshold under 800 • C were only 7.4% of that under 200 • C and revealed a severe heat damage phenomenon, which was consistent with the results of the scanning electron microscopy (SEM) with the appearance of a large number of thermal pores observed only under 800 • C. The failure modes tended to shear failure with the increasing inclination angle, indicating that the shear stress component can accelerate sliding instability of rocks. On the other hand, the failure patterns with different temperatures changed from combined splitting-shear failure (25-400 • C) to single shear failure (600 and 800 • C). The study results can provide an extremely important reference for underground thermal engineering construction under complex loading environment.Sustainability 2020, 12, 1255 2 of 25 design and thermal disaster prevention. Furthermore, in these underground thermal projects, due to the complexity of the stress environment, rocks are often affected by complex loading. Combined compression and shear loading are among the most common forms of rock encounter, such as irregular chamber [11][12][13]. Compared with the pure compressional state, additional shear stress can contribute to the rock failure [14,15]. Once these heat-treated rock masses are exposed to combined compression and shear loading, they may be more prone to instability. Hence, study of the effect of heat treatment on the mechanical and fracture behavior of rock material under combined compression and shear loading is absolutely critical for underground engineering design.The influence of heat treatment on rock properties is mainly reflected on its physical and mechanical properties, microstructure and ...

show abstract

“…The effect of strain rate on the mechanical behavior of various rocks has been widely studied in compression [3,4], tension [5][6][7][8][9], and bending [1,10]. Liang et al [11] studied the effects of loading rate on the fracture characteristics in the quasi-static region of granite rock.…”

Section: Introductionmentioning

confidence: 99%