Dynamic shear modulus and damping ratio of clay mixed with waste rubber using cyclic triaxial apparatus

Two of the most important parameters in dynamic analysis involving soils are the dynamic shear modulus and the damping ratio. In this study, a series of tests were performed on gravels. For comparison, some other tests carried out by other researchers were also collected. The test results show that normalized shear modulus and damping ratio vary with the shear strain amplitude, (1) normalized shear modulus decreases with the increase of dynamic shear strain amplitude, and as the confining pressure increases, the test data points move from the low end toward the high end; (2) damping ratio increases with the increase of shear strain amplitude, damping ratio is dependent on confining pressure where an increase in confining pressure decreased damping ratio. According to the test results, a reference formula is proposed to evaluate the maximum dynamic shear modulus, the best-fit curve and standard deviation bounds for the range of data points are also proposed.

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Experimental Study on Dynamic Characteristics of Ionic Soil Stabilizer Reinforcing Red Clay

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.1391 ◽

2011 ◽

Vol 374-377 ◽

pp. 1391-1395

Author(s):

Xue Song Lu ◽

Wei Xiang

Keyword(s):

Shear Modulus ◽

Shear Strain ◽

Dynamic Condition ◽

Damping Ratio ◽

Confining Pressure ◽

Natural Soil ◽

Dynamic Shear Modulus ◽

Dynamic Shear ◽

Red Clay ◽

Soil Stabilizer

Based on the red clay of Wuhan reinforced by Ionic Soil Stabilizer, the red clay soil is treated by different matches of ISS at first, then is tested in the Atterberg limits test and dynamic triaxia test. The results show that the plastic index decreases, and the red clay were greatly improved under the dynamic condition, the maximum dynamic shear modulus ratio acquired an incensement of 27.72% on average after mixing the ISS into the red clay. In addition, It was concluded that the confining pressure influenced the dynamic shear modulus and damping ratio to a certain extent. Given the same strain conditions, with the incensement of confining pressure increases, the dynamic shear modulus increased and the damping ratio decreased. Moreover, when plotting the dynamic shear modulus versus the dynamic shear strain, the similar curve can be formed for both the natural soil and the modified one, the dynamic shear modulus monotonously decreased with the incensement of the dynamic shear strain. However, the value of dynamic shear modulus differed in the same shear strain between the natural soil and the soil modified by ISS.

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Characterization of the Dynamic Properties of Clay–Gravel Mixtures at Low Strain Level

Sustainability ◽

10.3390/su12041616 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1616 ◽

Cited By ~ 3

Author(s):

Xianwen Huang ◽

Aizhao Zhou ◽

Wei Wang ◽

Pengming Jiang

Keyword(s):

Shear Modulus ◽

Shear Strain ◽

Mechanical Performance ◽

Dynamic Properties ◽

Damping Ratio ◽

Confining Pressure ◽

Strain Level ◽

Dynamic Shear Modulus ◽

Dynamic Shear ◽

Gravel Content

In order to support the dynamic design of subgrade filling engineering, an experiment on the dynamic shear modulus (G) and damping ratio (D) of clay–gravel mixtures (CGMs) was carried out. Forty-two groups of resonant column tests were conducted to explore the effects of gravel content (0%, 10%, 20%, 30%, 40%, 50%, and 60%, which was the mass ratio of gravel to clay), gravel shape (round and angular gravels), and confining pressure (100, 200, and 300 kPa) on the dynamic shear modulus, and damping ratio of CGMs under the same compacting power. The test results showed that, with the increase of gravel content, the maximum dynamic shear modulus of CGMs increases, the referent shear strain increases linearly, and the minimum and maximum damping ratios decrease gradually. In CGMs with round gravels, the maximum dynamic shear modulus and the maximum damping ratio are greater, and the referent shear strain and the minimum damping ratio are smaller, compared to those with angular gravels. With the increase of confining pressure, the maximum dynamic shear modulus and the referent shear strain increase nonlinearly, while the minimum and maximum damping ratios decrease nonlinearly. The predicting equation for the dynamic shear modulus and the damping ratio of CGMs when considering confining pressure, gravel content, and shape was established. The results of this research may put forward a solid foundation for engineering design considering low-strain-level mechanical performance.

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Experimental investigation of dynamic shear modulus and damping ratio of Qinghai-Tibet frozen silt under multi-stage cyclic loading

Cold Regions Science and Technology ◽

10.1016/j.coldregions.2019.102938 ◽

2020 ◽

Vol 170 ◽

pp. 102938

Author(s):

Futang Zhao ◽

Lijun Chang ◽

Wuyu Zhang

Keyword(s):

Experimental Investigation ◽

Cyclic Loading ◽

Shear Modulus ◽

Damping Ratio ◽

Dynamic Shear Modulus ◽

Dynamic Shear ◽

Multi Stage

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Dynamic Shear Modulus and Damping Ratio of Compacted Silty Clay Subjected to Freeze–Thaw Cycles

Journal of Materials in Civil Engineering ◽

10.1061/(asce)mt.1943-5533.0002893 ◽

2019 ◽

Vol 31 (10) ◽

pp. 04019244 ◽

Cited By ~ 1

Author(s):

Ruxin Jing ◽

Feng Zhang ◽

Decheng Feng ◽

Xueyan Liu ◽

Athanasios Scarpas

Keyword(s):

Shear Modulus ◽

Damping Ratio ◽

Dynamic Shear Modulus ◽

Silty Clay ◽

Dynamic Shear ◽

Freeze Thaw

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Study on Dynamic Characteristics of Rubber-Red Clay Mixtures

Advances in Materials Science and Engineering ◽

10.1155/2020/2343242 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Kaisheng Chen ◽

Qinqin Wang ◽

Dipu Luo ◽

Bo Zhou ◽

Kun Zhang

Keyword(s):

Particle Size ◽

Shear Modulus ◽

Vibration Frequency ◽

Damping Ratio ◽

Rubber Particle ◽

Confining Pressure ◽

Dynamic Strain ◽

Dynamic Shear Modulus ◽

Dynamic Shear ◽

Red Clay

Rubber powder formed from discarded tire rubber is mixed with red clay to form a rubber-red clay mixture. The dynamic triaxial test was carried out on the mixtures under different conditions. The effects of rubber content, rubber particle size, moisture content of mixed soil, compactness, confining pressure, and vibration frequency on shear strain relation, dynamic shear modulus, and damping ratio of the mixture were investigated. The results show that under the same dynamic strain, the dynamic shear stress-strain curve of rubber mixed soil decreases with the increase in rubber particle content and moisture content and decrease in rubber particle size. On the other hand, it increases with the increase in compactness, confining pressure, and vibration frequency, and as the dynamic strain increases, the τd-γd curve becomes more nonlinear. In addition, with the increase in the rubber particle content, the dynamic shear modulus decreased while the damping ratio increased. When the content was 2%, the change was fastest. After continued addition, it gradually became stable, and when the decrease in rubber particle size also shows the same pattern, 2.00 mm rubber-red clay mixture shows better structure. The water content has great influence on dynamic shear modulus and damping ratio of rubber-red clay mixtures. With the increase in compactness, confining pressure, and vibration frequency, the interaction between mixed soil particles was enhanced, the dynamic shear modulus increased, and the damping ratio decreased.

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