Study on the Static and Dynamic Fracturing Properties of Marble after Being Damaged Dynamically

A split Hopkinson pressure bar (SHPB) system was first used to perform the cyclic impact loading tests on notched semicircular bend (NSCB) marble specimens. Then, static and dynamic three-point bending tests were conducted on these dynamically damaged specimens, respectively. In the cyclic impact loading tests, the dynamic elastic modulus decreases gradually as the impact number increases, but dynamic cumulative damage exhibits a growing trend. In the static and dynamic three-point bending tests, when dynamic cumulative damage is less than 0.345, the dynamic fracture toughness values are larger than the static fracture toughness values, but the experimental data exhibit the opposite results when dynamic cumulative damage ranges from 0.345 to 0.369. Through the quantitative analysis of fracture surface morphologies, the roughness and area of the fracture surfaces increase with an increasing dynamic cumulative damage. Under the same dynamic cumulative damage of the specimens, both the roughness and area of the surfaces fractured by static three-point bending are larger than those fractured by dynamic three-point bending.

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Dynamic Responses of Red Sandstone with Fluid-Solid Coupling under Impact Loading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.724-725.1500 ◽

2013 ◽

Vol 724-725 ◽

pp. 1500-1505 ◽

Cited By ~ 4

Author(s):

Hua Lu ◽

Bo Huang ◽

Hua Shuai Zhao ◽

Meng Meng ◽

Ming Liang

Keyword(s):

Dynamic Characteristics ◽

Impact Loading ◽

Split Hopkinson Pressure Bar ◽

Test System ◽

Red Sandstone ◽

Porous Sandstone ◽

Cyclic Impact Loading ◽

Cyclic Impact ◽

The Impact ◽

Coupling Medium

The research object presented in this paper is coupling effect of porous red sandstone which is more frequently encountered. And this paper use the test system of Split Hopkinson Pressure Bar (SHPB) to survey the impact test action of different porosity red sandstone in different coupling medium in order to obtained the dynamic waveform of fluid-solid coupling red sandstone under impact loading using theoretical analysis and laboratory data. The paper analyzes the impact of porosity, coupling medium on the dynamics characteristics of red sandstone. Based on the experiment study of different coupling medium red sandstone under cyclic impact loading, this paper discussed the dynamic characteristics law of porous sandstone under cyclic impact loading and analyzed theoretically the mechanism of coupling medium under cyclic loading. Porosity has a great influence on dynamic performance of red sandstone. Coupling medium has certain influence on the dynamic characteristics of red sandstone. All those conclusions laid a theoretical foundation for practical application.

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Influence of Cyclic Impact Loading and Axial Stress on Dynamic Mechanical Properties of Burst-Prone Coal

Shock and Vibration ◽

10.1155/2021/6649308 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Shuang Gong ◽

Zhen Wang ◽

Lei Zhou ◽

Wen Wang

Keyword(s):

Mechanical Properties ◽

Impact Loading ◽

Coal Sample ◽

Impact Load ◽

Axial Stress ◽

Dynamic Mechanical Properties ◽

Dynamic Mechanical ◽

Cyclic Impact Loading ◽

Cyclic Impact ◽

The Impact

High in-situ stress and frequent dynamic disturbances caused by the mining process in deep coal mines can easily induce dynamic disasters such as coal burst. We conducted laboratory experiments to assess the effects of the axial stress loading and dynamic cyclic impact loading on the dynamic mechanical properties of burst-prone coals by using a modified split Hopkinson pressure bar (SHPB). Comparisons were made using two types of burst-prone and burst-resistant coal samples. The mineral components, organic macerals, and dynamic mechanical features of both burst-prone and burst-resistant coal samples were comparatively analyzed based on the obtained X-ray diffraction (XRD), optical microscope observations, and dynamic compressive stress-strain curves, respectively. The results of the microstructure analysis indicated a larger difference between the minimum and maximum reflectances of vitrinite for burst-prone coal. Compared to the burst-resistant coal samples, the burst-prone coals contained less corpocollinite and fusinite. While applying a high axial static load combined with cyclic impact load, the coal samples showed the characteristics of fatigue damage. The results also demonstrated that preaxial stress affected the burst resistance of coal samples. The greater the preaxial stress was, the less the coal samples could withstand the dynamic cyclic impact load. In comparison to the burst-resistant coal sample, the burst-prone coal sample showed a larger dynamic compressive strength and a lower deformation. They were also more positively capable of the propagation and activation of the coal burst. We believe that the results of the study are conducive to further understanding of the distribution of microcomponents of burst-prone coals. The results are also beneficial for realizing the dynamic mechanical characteristics of burst-prone coals under the impact of cyclic dynamic load.

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The Influence of H, W, H/E, H 3/E 2, Structure and Chemical Composition on the Resistance of Ti–B–(N), Mo–B–(N), Cr–B–(N), and Zr–B–(N) Coatings to Cyclic Impact Loading

Protection of Metals and Physical Chemistry of Surfaces ◽

10.1134/s2070205120060143 ◽

2020 ◽

Vol 56 (6) ◽

pp. 1190-1200

Author(s):

Ph. V. Kiryukhantsev-Korneev ◽

A. D. Sytchenko

Keyword(s):

Chemical Composition ◽

Impact Loading ◽

Cyclic Impact Loading ◽

Cyclic Impact

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Dynamic Properties of Thermally Treated Granite Subjected to Cyclic Impact Loading

Rock Mechanics and Rock Engineering ◽

10.1007/s00603-018-1606-y ◽

2018 ◽

Vol 52 (4) ◽

pp. 991-1010 ◽

Cited By ~ 20

Author(s):

Pin Wang ◽

Tubing Yin ◽

Xibing Li ◽

Shuaishuai Zhang ◽

Lv Bai

Keyword(s):

Impact Loading ◽

Dynamic Properties ◽

Cyclic Impact Loading ◽

Cyclic Impact ◽

Thermally Treated

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Dynamic Behavior of PET FRP and Its Preliminary Application in Impact Strengthening of Concrete Columns

Applied Sciences ◽

10.3390/app9234987 ◽

2019 ◽

Vol 9 (23) ◽

pp. 4987 ◽

Cited By ~ 5

Author(s):

Yu-Lei Bai ◽

Zhi-Wei Yan ◽

Togay Ozbakkaloglu ◽

Jian-Guo Dai ◽

Jun-Feng Jia ◽

...

Keyword(s):

Impact Loading ◽

Split Hopkinson Pressure Bar ◽

Concrete Columns ◽

Fiber Bundles ◽

Hopkinson Pressure Bar ◽

Strain Property ◽

Frp Composites ◽

Drop Weight ◽

The Impact ◽

Rupture Strain

Polyethylene terephthalate (PET) fiber has attracted significant attention for reinforced concrete (RC) structure rehabilitation due to its large rupture strain (LRS; more than 7%) characteristic and recyclability from waste plastic bottles. This study presents a dynamic tensile test of PET fiber bundles performed using a drop-weight impact system. Results showed that the tensile strength and the elastic modulus of the PET fiber bundles increased, whereas the failure strain and the toughness decreased with the increasing strain rate from 1/600 to 160 s−1. In addition, the performance of concrete confined with the PET fiber-reinforced polymer (FRP) under impact loading was investigated based on a 75 mm-diameter split Hopkinson pressure bar (SHPB) device and a drop-weight apparatus. For the SHPB test, owing to the large rupture strain property of PET FRP, the PET FRP-confined concrete exhibited significantly better performance under impact loading compared to its counterpart confined with carbon FRPs (CFRPs). During the drop-weight test, the confinement of the PET FRP composites to the concrete columns as external jackets not only improved the peak impact force, but also prolonged the impact process.

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Endurance of 55S2 steel under cyclic-impact loading in the presence of liquid media

Strength of Materials ◽

10.1007/bf00762325 ◽

1973 ◽

Vol 5 (5) ◽

pp. 621-624

Author(s):

V. V. Ermolaev ◽

A. V. Morzhakov ◽

A. V. Topkaev

Keyword(s):

Impact Loading ◽

Liquid Media ◽

Cyclic Impact Loading ◽

Cyclic Impact

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Fracture Toughness and Cracking Behaviour of SCC Compared to VC

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.577-578.205 ◽

2013 ◽

Vol 577-578 ◽

pp. 205-208

Author(s):

Sara Korte ◽

Veerle Boel ◽

Wouter de Corte ◽

Geert de Schutter

Keyword(s):

Fracture Toughness ◽

Fracture Process ◽

Critical Value ◽

Fracture Parameter ◽

Self Compacting Concrete ◽

Bending Tests ◽

Three Point Bending ◽

Notched Specimens ◽

Subsequent Determination

Vibrated concrete (VC) and self-compacting concrete (SCC) have a substantially different composition, resulting in dissimilar mechanical properties regarding cracking behaviour. The critical value of the mode I stress-intensity factor KICis an appropriate fracture parameter for evaluating fracture toughness and can be obtained from three-point bending tests (3PBT) on small, notched specimens. Subsequent determination of the energy release rate thus allows to examine the crack propagation and fracture process of both concrete types. This paper describes the results of such 3PBTs on samples, made from VC and SCC. Evaluation of the cracking behaviour, derived from these results, reveals remarkable differences.

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