Freeze–Thaw Damage Characterization of Cement-Stabilized Crushed Stone Base with Skeleton Dense Gradation

Abstract

The skeleton dense graded cement-stabilized crushed stone base is a widely used material for road construction. However, this material is susceptible to freeze–thaw damage, which can lead to degradation and failure, for which there is still a lack of an in-depth understanding of the freeze–thaw damage characteristics. This study aims to assess the mechanical performance and the freeze–thaw damage characteristics of the cement-stabilized crushed stone base with skeleton dense gradation based on a mechanical test and acoustic technology in a laboratory. There is a gradually increasing trend in the mass loss rate of the base material with an increase in freeze–thaw cycles. The curve steepens significantly after 15 cycles, following a parabola-fitting pattern relationship. The compressive strength of the cement-stabilized crushed stone base also decreased with a parabola-fitting pattern, and the decrease rate may accelerate as the freeze–thaw cycles increase. The resilience modulus of the base material decreased with increasing freeze–thaw cycles, following a parabolic trend. This suggests that the material’s resistance to freeze–thaw damage decreases with increasing cycles. The ultrasonic wave velocity decreased with increasing freeze–thaw cycles, exhibiting a parabolic trend. This decline can be attributed to microcracks and defects developing within the material, offering insights for monitoring and predicting its service life. The damage progression of the cement-stabilized crushed stone base was found to occur in three stages: initial, stationary, and failure. The duration of stage I increased with freeze–thaw cycles, while the duration of stage III decreased. The findings provide valuable insights into the mechanisms and processes of freeze–thaw damage in a cement-stabilized crushed stone base with skeleton dense gradation.

Performance Evaluation and Degradation Analysis of Suspended Dense Broken Stone Road Foundation Stabilized by Cement under Conditions of Freezing and Thawing

“…This is primarily attributed to the expansion of water content within the broken stone road foundation stabilized by cement during freezing and its contraction during thawing, ultimately causing microcracks and detachment within the structure. These structural flaws can significantly compromise the mechanical properties and lifespan of a broken stone road foundation stabilized by cement [38,39]. Consequently, it is imperative to adopt measures aimed at reducing the water content in a broken stone road foundation stabilized by cement or enhancing its resistance to freezing during both construction and usage to guarantee its longevity.…”

“…As freezing and thawing processes accumulate, the loss rate exhibits a parabolic pattern. This behavior is likely attributed to progressive accumulation of microcracks and defects within the broken stone road foundation stabilized by cement, ultimately leading to a precipitous decline in the ultrasonic wave velocity loss rate beyond a certain threshold of freezing and thawing processes [38]. In conclusion, this discovery offers profound insights into the monitoring and prediction of the mechanical properties and durability of a broken stone road foundation stabilized by cement structures under freezing and thawing processes, thus enhancing our understanding of their performance in such environments.…”

“…Figure 9 depicts the relationship between AE parameters and stress levels across varying freezing-thawing cycles. According to Figure 9, the entire process of failure and cracking in the suspended dense graded broken stone road foundation stabilized by cement, under compressive loading, can be categorized into three distinct stages [38]. Stage I: Initial Damage Phase-In this initial phase, the low-level stress undergoes minimal alterations, and no fresh cracks emerge.…”