Study on Dynamic Modulus and Damping Characteristics of Modified Expanded Polystyrene Lightweight Soil under Cyclic
Huaqiang Tao1,2, Wenqian Zheng1,2, Xuhui Zhou1,2
1School of Civil Engineering, Shaoxing University, Shaoxing 312000, China.
Polymers
|April 28, 2023
Summary
This study examined expanded polystyrene (EPS) lightweight soil modified with lime and fly ash. Results show EPS content significantly impacts dynamic properties, with 0.5%-1% EPS optimal for road engineering applications.
Area of Science:
- Geotechnical Engineering
- Materials Science
- Civil Engineering
Background:
- Expanded polystyrene (EPS) lightweight soil is increasingly used in soft soil areas due to its low weight and eco-friendly properties.
- Understanding the dynamic behavior of modified lightweight soils is crucial for their application in infrastructure projects.
Purpose of the Study:
- To investigate the dynamic characteristics of sodium silicate modified lime and fly ash treated EPS lightweight soil (SLS) under cyclic loading.
- To determine the influence of EPS particle content on the dynamic elastic modulus (E) and damping ratio (λ) of SLS.
Main Methods:
- Dynamic triaxial tests were conducted on SLS with varying EPS particle content, confining pressures (σ3), amplitudes, and cycle times.
- Mathematical models were developed to describe the relationship between E, cycle times, and σ3.
Main Results:
- EPS particle content critically affects the E and λ of SLS, with E decreasing as EPS content increases.
- E decreased by up to 60% with EPS content between 1-1.5%. The internal structure shifted from parallel to series.
- E decreased with increasing σ3 and amplitude, while λ generally decreased. E exhibited a power function relationship with the number of cycles.
Conclusions:
- An EPS content of 0.5% to 1% is optimal for SLS in this study.
- The established dynamic elastic modulus prediction model accurately reflects SLS behavior under varying conditions, offering a theoretical basis for practical road engineering.
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