Effect of EPS beads in lightening a typical zeolite and cement-treated sand

• Published in: Bulletin of engineering geology and the environment 2021-11, Vol.80 (11), p.8615-8632
• Main Authors: Khajeh, Aghileh, Ebrahimi, Seyed Abolfazl, MolaAbasi, Hossein, Jamshidi Chenari, Reza, Payan, Meghdad
• Format: Article
• Language: English
• Subjects: Earth and Environmental Science; Earth Sciences; Foundations; Geoecology/Natural Processes; Geoengineering; Geotechnical Engineering & Applied Earth Sciences; Hydraulics; Nature Conservation; Original Paper
• ISSN: 1435-9529; 1435-9537
• DOI: 10.1007/s10064-021-02458-1

The current study aims to assess the influence of EPS beads inclusion on the strength properties of stabilized poorly-graded sands. Various contents of zeolite and cement as stabilizing agents, with the total amounts of 4, 8, and 12% by dry soil weight, and also 0, 0.25, and 0.5% weight ratios of EPS beads ( η ) are examined. Zeolite is opted among a variety of pozzolanic materials so as to replace a part of cement (0, 10, 30, 50, 70, and 90%) due to its superior environmentally friendly properties. The stress–strain behavior, unconfined compressive strength (UCS), peak strain energy ( E u ), and California bearing capacity (CBR) of the zeolite and cement-treated sand-EPS beads mixtures are investigated through several mechanical tests. Results showed that zeolite incorporation (with the optimum value of 30% replacement) improves the UCS and CBR values significantly and the reduction observed by the use of EPS beads is well-compensated. At η = 0.25 % , the peak strain energy is also enhanced. Active composition (AC), which refers to the minimum value of CaO or the sum of Al 2 O 3 and SiO 2 in the mixture, is suggested to render a unique power equation that can readily estimate the UCS and CBR values. It was concluded that the increase of AC and porosity ( n ) of the mixture, respectively, increases and decreases the strength parameters. Therefore, by the increase of n/AC ratio, the values of strength parameters diminish. Finally, with the aid of the presented power formulas, high-accuracy equations are proposed to correlate the UCS and CBR values of the samples to the key parameter (n/AC).