Fractures and Acoustic Emission Features of Non-persistent Jointed Rocks Subjected to Freeze–Thaw-Compression Load: Experimental Insights

This paper presents the results of investigations into the effect of freeze–thaw cycling on the failure of fibre-cement boards and on the changes taking place in their structure. Fibre-cement board specimens were subjected to one and ten freeze–thaw cycles and then investigated under three-point bending by means of the acoustic emission method. An artificial neural network was employed to analyse the results yielded by the acoustic emission method. The investigations conclusively proved that freeze–thaw cycling had an effect on the failure of fibre-cement boards, as indicated mainly by the fall in the number of acoustic emission (AE) events recognized as accompanying the breaking of fibres during the three-point bending of the specimens. SEM examinations were carried out to gain better insight into the changes taking place in the structure of the tested boards. Interesting results with significance for building practice were obtained.

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Experimental Study on the Performance Decay of Permeable Asphalt Mixture in Seasonally Frozen Regions under Freeze-Thaw Cycles

Sustainability ◽

10.3390/su12072966 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2966 ◽

Cited By ~ 3

Author(s):

Chao Chai ◽

Yong-Chun Cheng ◽

Yuwei Zhang ◽

Yu Chen ◽

Bing Zhu

Keyword(s):

Acoustic Emission ◽

Asphalt Mixture ◽

Temperature Stability ◽

High Temperature Stability ◽

Air Voids ◽

Particle Loss ◽

Seasonal Freezing ◽

Freeze Thaw ◽

Splitting Test ◽

Air Void

This paper focuses on the freeze-thaw cycles (F-T cycles) resistance of porous asphalt mixture (PAM) with different air voids in order to explore the gradation of the PAM suitable for seasonal freezing regions. Three sets of PAMs with 18%, 21%, and 25% air voids were designed. After 0–20 F-T cycles, the effects of F-T cycles on the performance degradation of three groups of PAMs were studied by performing a low-temperature splitting test with acoustic emission technology, a normal temperature splitting test, a compression test, a Cantabro particle loss test, and a dynamic creep test. The results show that the damage process of PAM caused by multiple F-T cycles could be more clearly defined by acoustic emission parameters. In addition, the larger the air void, the smaller its indirect tensile strength and compression strength, and the worse its particle loss resistance and high-temperature stability, which made the adverse effect of F-T cycles more significant. Therefore, the air void of PAM used in seasonal freezing regions is suggested to be less than 21%.

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Energy dissipation capacity of fibre reinforced concrete under biaxial tension–compression load. Part II: Determination of the fracture process zone with the acoustic emission technique

Cement and Concrete Composites ◽

10.1016/j.cemconcomp.2015.07.003 ◽

2015 ◽

Vol 62 ◽

pp. 187-194 ◽

Cited By ~ 9

Author(s):

Elmar K. Tschegg ◽

Andreas Schneemayer ◽

Ildiko Merta ◽

Klaus A. Rieder

Keyword(s):

Acoustic Emission ◽

Fracture Process ◽

Fracture Process Zone ◽

Biaxial Tension ◽

Process Zone ◽

Fibre Reinforced Concrete ◽

Acoustic Emission Technique ◽

Compression Load ◽

Energy Dissipation Capacity

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Influence of Freeze-Thaw Cycles on Acoustic Emission Characteristics of Granite Samples under Triaxial Compression

Advances in Civil Engineering ◽

10.1155/2021/5571680 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Zhandong Su ◽

Ke Geng ◽

Fubiao Zhou ◽

Jinzhong Sun ◽

Huayan Yu

Keyword(s):

Acoustic Emission ◽

Triaxial Compression ◽

Peak Frequency ◽

Dominant Frequency ◽

P Wave ◽

Cold Regions ◽

Freeze Thaw ◽

Ae Signal ◽

The Stability ◽

Granite Samples

Understanding the acoustic emission (AE) characteristics of rocks that have undergone freeze-thaw cycling is of great significance for the use of AE technology to monitor the stability of rock masses in cold regions. A series of freeze-thaw cycling experiments and triaxial compression AE tests of granite samples were performed. The results show that, with an increasing number of freeze-thaw cycles, the P-wave velocity and peak AE intensity of granite show a substantial downward trend. The AE ringing counts during triaxial compression can be divided into three stages: abrupt period, calm period, and failure period. The overall change of the characteristic AE signal of granite samples that underwent different freeze-thaw cycles is the same. The AE signal during the destruction of granite occurs in clear dual dominant frequency bands. The peak frequency increases with increasing load time, and this trend becomes less clear as the number of freeze-thaw cycles increases. Overall, the peak frequency distribution tends to change from high to low with an increasing number of freeze-thaw cycles. The results provide basic data for rock mass stability monitoring and prediction, which is of great significance for engineering construction and management in cold regions.

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Fracture Damage Properties of SBS-Modified Asphalt Mixtures Reinforced with Basalt Fiber after Freeze-Thaw Cycles Using the Acoustic Emission Approach

Applied Sciences ◽

10.3390/app10093301 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3301 ◽

Cited By ~ 2

Author(s):

Chunyu Liang ◽

Junchen Ma ◽

Peilei Zhou ◽

Guirong Ma ◽

Xin Xu

Keyword(s):

Acoustic Emission ◽

High Temperature ◽

Asphalt Mixture ◽

Basalt Fiber ◽

Load Level ◽

Asphalt Mixtures ◽

Fracture Characteristics ◽

Freeze Thaw ◽

Ae Signal ◽

Fracture Damage

This paper focuses on the fracture damage characteristics of styrene-butadiene-styrene (SBS)-modified SMA-13 specimens with basalt fiber under various freeze-thaw (F-T) cycles. SBS-modified stone mastic asphalt (SMA)-13 specimens with basalt fiber were prepared, first, using the superpave gyratory compaction method. Then, asphalt mixture specimens processed with 0–21 F-T cycles were adopted for the high-temperature compression and low-temperature splitting tests. Meanwhile, the acoustic emission (AE) test was conducted to evaluate the fracture characteristics of the asphalt mixture during loading. The results showed that the AE parameters could effectively reflect the damage fracture characteristics of the asphalt mixture specimen during the high-temperature compression and low-temperature splitting processes. The fracture damage of the asphalt mixture specimens during compression or splitting are classified into three stages based on the variation of the AE signals, i.e., when the load level is below 0.1~0.2 during the first stage and the load level is 0.1–0.9 or 0.2–0.8 during the second stage. The AE signal amplitude and count show clear correlations with the compression and splitting load levels. Meanwhile, the AE signal clarifies the formation, development, and failure of internal damage for the asphalt mixture specimens during the compression and splitting processes. The intensity (value and density) of the AE signal parameters of asphalt mixture decreases with increasing F-T cycles. It is evident that the F-T cycle has a significant adverse effect on the mechanical strength of asphalt mixture, which makes asphalt mixtures more likely to cause early failure.

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