scholarly journals Localized Enhancement of Infrared Radiation Temperature of Rock Compressively Sheared to Fracturing Sliding: Features and Significance

2021 ◽  
Vol 9 ◽  
Author(s):  
Xiangxin Liu ◽  
Lixin Wu ◽  
Yanbo Zhang ◽  
Wenfei Mao
Keyword(s):  
Rock Mass ◽  
Infrared Radiation ◽  
Wave Length ◽  
Regional Scale ◽  
Local Stress ◽  
Radiation Temperature ◽  
Rock Fracturing ◽  
Thermoelastic Effect ◽  
Frictional Sliding ◽  
Tectonic Earthquakes

Previous experiments indicated that infrared radiation temperature (IRT) was applied in monitoring rock stress or rock mass fracturing, and abnormal IRT phenomena preceding rock failure or tectonic earthquakes were frequently reported. However, the characteristics of IRT changing with rock fracturing and frictional sliding are not clear, which leaves much uncertainties of location and pattern identification of stress-produced IRT. In this study, we investigated carefully the localized IRT enhancement of rock compressively sheared to fracturing and sliding (named as CSFS) with marble and granite specimens. Infrared thermogram and visible photos were synchronously observed in the process of rock CSFS experiment. We revealed that localized IRT enhancement was determined by local stress locking, sheared fracturing, and frictional sliding, and the relations between the Kcv of IRT and the shear force are almost linear in wave length 3.7–4.8 μm. In the process of rock CSFS, the detected ΔIRT which resulted from thermoelastic effect is 0.418 K, while the detected ΔIRT resulted from friction effect reaches up to 10.372 K, which is about 25 times to the former. This study is of potential values for infrared detection of rock mass failure in engineering scale and satellite remote sensing of the seismogenic process in the regional scale.

scholarly journals Pathologic analysis on hyperplasia of mammary gland with different syndromes based on infrared radiation temperature of acupoints

2012 ◽  
Vol 32 (3) ◽  
pp. 382-387 ◽  
Author(s):  
Yafang Wang ◽  
Xueyong Shen ◽  
Jian Ying ◽  
Juanjuan Zheng ◽  
Shengfang Hu ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Infrared Radiation ◽  
Radiation Temperature ◽  
Pathologic Analysis

scholarly journals Influence of prefabricated fissure angle on sandstone damage and infrared radiation temperature characteristics

2018 ◽  
Vol 15 (4) ◽  
pp. 1187-1196
Author(s):  
Cheng Fuqi ◽  
Li Zhonghui ◽  
Li Guoai ◽  
Wei Yang ◽  
Yin Shan ◽  
...  
Keyword(s):  
Infrared Radiation ◽  
Radiation Temperature ◽  
Temperature Characteristics

scholarly journals High-energy seismic events in Legnica–Głogów Copper District in light of ASG-EUPOS data

2019 ◽  
Vol 107 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Zbigniew Szczerbowski
Keyword(s):  
Rock Mass ◽  
Regional Scale ◽  
Geophysical Methods ◽  
Geodetic Network ◽  
High Energy ◽  
Tectonic Activity ◽  
Baseline Length ◽  
Seismic Events ◽  
Gnss Data ◽  
Mining Tremors

AbstractSeismic events in the area of Poland are related mostly to copper and coal mining, and they are regarded as the most dangerous natural hazard. Although development of geomechanical modelling as the development of geophysical methods determining seismic hazard are evident, low predictability of the time-effect relationship still remains. Geomechanical models as geophysical data analysis highlight the interaction between parts of rock mass or allow to reconstruct the way of rock mass destruction and to understand the processes that take place in the high-energy tremors.However, the association of larger mining tremors with pre-existing geological features has been reported by many investigators; in geomechanical practice, investigations of rock mass condition concentrate on this problem in the local scale. Therefore, the problem of relations between high-energy seismic events in Legnica–Głogów Copper District (LGCD) and regional scale deformations of terrain surface resulting from possible tectonic activity is discussed in this paper. The GNSS data evaluated from the observations of ASG-EUPOS (Active Geodetic Network – EUPOS) stations in the area of LGCD and in the adjacent areas is analysed in this study. Temporal variation of distances between the stations and evaluated on that base so called apparent strain was combined with the occurrence of high-energy tremors. Consequently, after the examination and analysis of occurrences of mining tremors, it is found that high-energy seismic events and periods of strain accumulation evaluated from GPS/GNSS data have temporal relations. Although the seismic events were triggered by mining, nearly all the events with energy E > 108 J occurred in the periods when the analysed stations’ positions demonstrated a decrease in the baseline length.

scholarly journals Liquid CO2 Phase-Transition Rock Fracturing: A Novel Technology for Safe Rock Excavation

2021 ◽  
Vol 12 (1) ◽  
pp. 68
Author(s):  
Haoyue Sui ◽  
Tianming Su ◽  
Ruilin Hu ◽  
Ke Yang ◽  
Yaxing Cheng
Keyword(s):  
Phase Transition ◽  
Rock Mass ◽  
Processing System ◽  
Field Tests ◽  
Fractal Dimensions ◽  
Dominant Frequency ◽  
Rock Breaking ◽  
Rock Breakage ◽  
Rock Fracturing ◽  
Liquid Co2

In order to determine the applicability of liquid CO2 phase-transition fracturing technology in rock mass excavations, the principles of CO2 phase-transition fracturing were analyzed, and field tests of liquid CO2 phase-transition fracturing were performed. An “Unmanned Aerial Vehicle (UAV) camera shooting + Microstructure Image Processing System (MIPS) analyzing” method was used to acquire the rock mass characteristics. Further, the Hilbert–Huang Transform (HHT) energy analysis principle was adopted to analyze the characteristics of fracturing vibration waves. The experimental results showed that during the process of fracturing, there were both dynamic actions of rock breakage due to excitation stress wave impacts, and quasi-static actions of rock breakage caused by gasification expansion wedges. In semi-infinite spaces, rock-breakage zones can mainly be divided into crushing zones, fracture zones, and vibration zones. At the same time, under ideal fracturing effects and large volumes, the fracturing granularity will be in accordance with the fractal laws. For example, the larger the fractal dimensions, the higher the proportion of small fragments, and vice versa. Moreover, the vibration waves of the liquid CO2 phase-transition fracturing have short durations, fast attenuation, and fewer high-frequency components. The dominant frequency band of energy will range between 0 and 20 Hz. The liquid CO2 phase-transition fracturing technology has been observed to overcome the shortcomings of traditional explosive blasting methods and can be applied to a variety of rock types. It is a safe and efficient method for rock-breaking excavations; therefore, the above technology effectively provides a new method for the follow-up of similar engineering practices.

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