Permeability Characteristics and Mechanism of Silicone-Hydrophobic-Powder-Modified Compacted Loess

Xu Duan (), Di Xiao, Yu Zou, Qi Dong, Wanjun Ye and Liyun Tang
Additional contact information
Xu Duan: School of Architectural and Civil Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
Di Xiao: School of Architectural and Civil Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
Yu Zou: Shaanxi Science & Technology Holding Group Co., Ltd., Xi’an 710077, China
Qi Dong: Shaanxi Science & Technology Holding Group Co., Ltd., Xi’an 710077, China
Wanjun Ye: School of Architectural and Civil Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
Liyun Tang: School of Architectural and Civil Engineering, Xi’an University of Science and Technology, Xi’an 710054, China

Sustainability, 2023, vol. 15, issue 8, 1-16

Abstract: This paper proposes the addition of an environmentally friendly silicone hydrophobic powder (SHP) to compacted loess to enhance its impermeability and reduce the settlement caused by wetting deformation. A flexible wall permeability test was conducted to examine the permeability coefficient of compacted loess with different dry densities mixed with different proportions of the SHP. Water drop infiltration testing, low-temperature drying testing, low-field nuclear magnetic resonance testing, and scanning electron microscopy were performed to clarify the occurrence state and permeability reduction mechanism of the SHP between loess particles from the microscopic viewpoint of the loess structure. The permeability coefficient of the compacted loess decreases significantly after adding 1–3% SHP. Specifically, the permeability coefficient of the loess with low compaction degree (1.35 g/cm 3 ) decreases by 87% after the addition of 3% SHP. Moreover, the permeability coefficient of the loess with a compaction degree of 1.50 g/cm 3 decreases from 1.58 × 10 −6 to 7.9 × 10 −8 cm/s. When the SHP is added to compacted loess, filling and adsorption effects occur: The filling effect decreases the proportion of large pores in the loess. The adsorption effect allows the SHP to encapsulate the loess particles to form a hydrophobic film layer, which leads to the formation of a non-closed hydrophobic structure. This phenomenon decreases the water flow capacity while ensuring the water evaporation capacity inside the loess. The findings demonstrate the potential of adding SHP to enhance the loess impermeability and facilitate and optimize the anti-seepage treatment of various loess filling projects.

Keywords: high fill; compacted loess; permeability coefficient; hydrophobic material (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/15/8/6606/pdf (application/pdf)
https://www.mdpi.com/2071-1050/15/8/6606/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:15:y:2023:i:8:p:6606-:d:1122803

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().