Impact of various binders on loess durability subjected to different freeze-thaw regimes

Abstract

Freezing and thawing (F/T) is an important occurrence in cold regions influencing soil geotechnical characteristics. Current study investigates effects of lime, Rice Husk Ash (RHA) and Nano-clay on unconfined compressive strength and F/T of loess under open and closed schemes. Loess was treated with 2, 4, 6 and 8% lime and RHA and 0.5, 1.0, 1.5 and 2% Nano-clay and compacted at optimum conditions. Samples were cured for 1, 7, 14 and 28 days at 35 °C before freezing at −23 °C and thawing at room temperature for 24 h intervals. Tests conducted on untreated and RHA and Nano-clay treated samples showed total loss of strength after one F/T cycle with noticeable weight and volume changes by samples subjected to open F/T. Exposing samples to closed F/T resulted in smaller changes in volume and strength. Samples treated independently with lime or concurrently with RHA and Nano-clay showed significant resistance to F/T particularly with curing time. Formations of chemical compounds bind particles, reduce void ratio resulting in a solid durable structure resisting freezing. Open F/T proved more detrimental than closed F/T scheme exhibiting moisture accessibility to be a dominant factor on F/T process.

Keywords:

• Lime
• loess
• rice husk ash
• nano-clay
• freeze-thaw
• strength

Disclosure statement

The authors declared that they have no conflicts of interest in this work.

Data availability statement

Some or all data, models or code that support the findings of the current study are available from the corresponding author upon reasonable request.