3D mesoscopic modelling on the dynamic properties of coral aggregate concrete under direct tension

This paper presents the results of an experimental study to investigate dynamic properties of polypropylene fiber-reinforced concrete beams with lightweight expanded shale (ES) and tire-derived aggregates (TDA). The mixture design followed past experiences in combining ES and TDA to enhance toughness and energy absorption in flexural behavior. The new mixture also contained 2% fiber by volume to improve such properties further. Experiments included compressive testing on cylindrical specimens as well as flexural testing on rectangular specimens to verify mechanical properties of fiber-reinforced tire-derived lightweight aggregate concrete (FRTDLWAC) subject to static loading. The results of these experiments confirmed reduction of mechanical strength due to addition of TDA and improvements in flexural strength due to fiber reinforcement. The dynamic testing included non-destructive impact loads applied to flexural specimens using a standard Schmidt hammer. A high-speed camera recorded the response of the system at 200 frames per second to allow detailed observations and measurements. Interpretation of energy-based dynamic results revealed that TDA enhances energy absorption through damping in flexural behavior. Results also indicated that fiber reinforcement reduces the amount of absorbed dynamic energy, even though; it enhances the absorbed strain energy due to crack bridging effect.

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Dynamic properties of stainless steel under direct tension loading using a simple gas gun

EPJ Web of Conferences ◽

10.1051/epjconf/201818302035 ◽

2018 ◽

Vol 183 ◽

pp. 02035 ◽

Cited By ~ 3

Author(s):

Anatoly Bragov ◽

Alexander Konstantinov ◽

Leopold Kruszka ◽

Andrey Lomunov ◽

Andrey Filippov

Keyword(s):

Stainless Steel ◽

Strain Rate ◽

High Speed ◽

Split Hopkinson Pressure Bar ◽

Dynamic Properties ◽

Tensile Load ◽

Hopkinson Pressure Bar ◽

Direct Tension ◽

Stress Strain ◽

Gas Gun

The combined experimental and theoretical approach was applied to the study of high-speed deformation and fracture of the 1810 stainless steel. The material tests were performed using a split Hopkinson pressure bar to determine dynamic stress-strain curves, strain rate histories, plastic properties and fracture in the strain rate range of 102 ÷ 104 s-1. A scheme has been realized for obtaining a direct tensile load in the SHPB, using a tubular striker and a gas gun of a simple design. The parameters of the Johnson-Cook material model were identified using the experimental results obtained. Using a series of verification experiments under various types of stress-strain state, the degree of reliability of the identified mathematical model of the behavior of the material studied was determined.

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Dynamic properties of concrete in direct tension

Cement and Concrete Research ◽

10.1016/j.cemconres.2006.03.003 ◽

2006 ◽

Vol 36 (7) ◽

pp. 1371-1378 ◽

Cited By ~ 123

Author(s):

Dongming Yan ◽

Gao Lin

Keyword(s):

Dynamic Properties ◽

Direct Tension

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Dynamic properties of large aggregate concrete under triaxial loading

Magazine of Concrete Research ◽

10.1680/macr.14.00225 ◽

2015 ◽

Vol 67 (6) ◽

pp. 282-293 ◽

Cited By ~ 7

Author(s):

Linlin Shi ◽

Licheng Wang ◽

Yupu Song ◽

Lu Shen

Keyword(s):

Dynamic Properties ◽

Triaxial Loading ◽

Large Aggregate ◽

Aggregate Concrete

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Discussion: Dynamic properties of large aggregate concrete under triaxial loading

Magazine of Concrete Research ◽

10.1680/jmacr.16.00420 ◽

2017 ◽

Vol 69 (6) ◽

pp. 317-319

Author(s):

Linlin Shi ◽

Licheng Wang ◽

Yupu Song ◽

Lu Shen ◽

José R. Martí-Vargas

Keyword(s):

Dynamic Properties ◽

Triaxial Loading ◽

Large Aggregate ◽

Aggregate Concrete

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Mechanical and Damping Properties of Recycled Aggregate Concrete Modified with Air-Entraining Agent and Polypropylene Fiber

Materials ◽

10.3390/ma13082004 ◽

2020 ◽

Vol 13 (8) ◽

pp. 2004 ◽

Cited By ~ 2

Author(s):

Chonggang Zhou ◽

Xingwang Pei ◽

Wenlong Li ◽

Yijun Liu

Keyword(s):

Mechanical Performance ◽

Dynamic Properties ◽

Damping Ratio ◽

Polypropylene Fiber ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Favorable Effect ◽

Damping Properties ◽

Aggregate Concrete ◽

Negative Effect

In this study, recycled aggregate concrete (RAC) modified with polypropylene fiber (PP) and air-entraining agent (AGA) was prepared, and the effects of PP and AGA on the static (compressive strength, Young’s modulus, and splitting tensile strength) and dynamic properties (dynamic modulus of elasticity and damping ratio) of RAC were investigated. The experimental results showed that the addition of an AGA and PP had a favorable effect on the damping ratio of the concrete, however, the addition of the AGA had a slightly negative effect on the mechanical performance of the concrete. The AGA and PP contents required to achieve the optimum damping ratio of the concrete with the least reduction in the mechanical performance were 0.02% and 0.10%, respectively. Furthermore, the addition of AGA was more effective than that of PP in improving the damping property of the concrete.

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Dynamic Compressive Strength of Recycled Aggregate Concrete

International Journal of Materials ◽

10.46300/91018.2021.8.7 ◽

2021 ◽

Vol 8 ◽

pp. 56-61

Author(s):

Shamsoon Fareed ◽

Asad-ur-Rehman Khan ◽

Samra Masood

Keyword(s):

Dynamic Properties ◽

Compressive Loading ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Recycled Aggregates ◽

Maximum Height ◽

Environmental Preservation ◽

Aggregate Concrete ◽

Drop Hammer ◽

Static Mechanical

Over the years the construction waste has enormously increased, this may be attributed to different factors such as (i) demolition (ii) accidents (iii) impact loads (iv) earthquakes. These activities have caused an increasing burden on already exhausted waste management system globally. As a result, the concrete waste produced in a large quantity has become a major issue to manage due to limited landfill sites. Therefore, the recycling of waste concrete can prove to be beneficial and necessary for the environmental preservation and effective utilization of natural resources. Number of studies have been conducted to study the static mechanical properties of recycled aggregate concrete; however, limited test data has been published which focused on the dynamic properties of the concrete prepared with recycled coarse aggregates. Therefore, in this investigation aim was to study the behavior of recycled aggregates concrete under increasing dynamic compressive loading. For this purpose, cylindrical specimens having a diameter of 100 mm and height of 200 mm were used. These specimens have been prepared with constant concrete mix ratio, having varying percentages of RA such as 0%, 30%, and 50% 70 % and 100%. The dynamic compressive behaviour was studied by using drop hammer system. The height drop hammer system consist of a frame having a maximum height of 15ft. Firstly, three samples (1, 1R, 2R) from each percentage replacement (0%, 30%, 50%, 70% and 100%) were tested on six different velocities of 2.44m/s, 3.45m/s, 4.23m/s, 4.89m/s, 5.46m/s and 7.45m/s with varying strain rates of 12.04/s, 17.00/s, 20.83/s, 24.08/s, 26.89/s and 36.73/s respectively. Weight of the drop hammer was 10 kg. Based on the detailed experimental investigation, it was found that the behaviour of the recycled aggregate concrete under dynamic loading differ significantly from the static loading.

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COMPREHENSIVE STUDY OF THE PROPERTIES OF FINE-GRAINED CONCRETE UNDER DYNAMIC TENSION AND SHEAR

Problems of Strength and Plasticity ◽

10.32326/1814-9146-2020-82-4-442-457 ◽

2020 ◽

Vol 82 (4) ◽

pp. 442-457

Author(s):

M.E. Gonov

Keyword(s):

Shear Strength ◽

Dynamic Properties ◽

Test Sample ◽

Dynamic Strain ◽

Shear Stresses ◽

Direct Tension ◽

Fine Grained ◽

Kolsky Method ◽

Wide Range ◽

Comprehensive Study

An experimental study of the dynamic properties of fine-grained concrete under tensile and shear stresses has been carried out. A comprehensive study of the dynamic properties of concrete allows obtaining experimental data and constants. These data and constants are needed to equip dynamic strain and fracture models. The system of experiments is based on modifications of the Kolsky method. This system of experiments allows one to determine a wide range of strength and time characteristics of concrete under shock loading. The experimental setup according to the Kolsky method includes a system of measuring rods between which a test sample is installed, a gas gun for accelerating a cylindrical striker, strain gauges, a speed meter, recording and computing equipment with a software package. Conducted dynamic tests of concrete in a wide range of deformation rates (102–104 s–1). In experiments on direct tension and to determine the ultimate tensile stress of fine-grained concrete during splitting, two speed modes are implemented. In tests of shear strength, a modification of the Hopkinson split bar method was used to determine the dynamic shear strength, in which a sample made of the material under study is located in a rigid holder cut at an angle to the sample axis. The pulse recorded in the reference dipstick is used to plot the shear stress in the sample over time. Shear tests were carried out for three speeds. The results of the performed experiments on tensile, splitting and shearing are presented in the form of diagrams of stress versus deformation and stress versus time. The obtained characteristics can be used to equip computational experiments in the study of the strength of concrete structures subjected to dynamic influences.

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