Wang Long, Xiong Houren, Huang Junguang, Wen Minjie, Ding Pan, Zhang Yiming
School of Civil and Transportation Engineering, Hebei University of Technology, Xiping Road 5340, Tianjin 300401, China.
School of Civil Engineering and Architecture, Jiaxing University, Jiaxing 314000, China.
Materials (Basel). 2025 Jan 3;18(1):178. doi: 10.3390/ma18010178.
Waste slurry, a major by-product of urban construction, is produced in rapidly increasing volumes each year. Dehydrated waste slurry has potential as a roadbed material; however, its performance in freeze-thaw environments, which can induce frost heave and thaw settlement, and the mechanism of the influence of freeze-thaw cycles on its macro and micro properties are still unclear and need thorough investigation. This study explores the macroscopic and microscopic properties of waste slurry subjected to freeze-thaw cycles. We conducted unconfined compressive strength (UCS) and triaxial unconsolidated undrained (UU) shear tests, focusing on fissure compaction, elastic deformation, plastic yielding, and strain hardening stages. The results reveal a decrease in strength and elastic modulus with increasing freeze-thaw cycles, as well as in the damage degree generated by freeze-thaw cycles. To uncover the underlying microscopic mechanisms, we performed Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and mercury intrusion porosimetry (MIP) analyses. These tests highlighted the evolution of pores and microcracks during freeze-thaw cycles. These results have important reference values for the reutilization of waste slurry discharged from large-diameter bored piles for roadbed backfill materials that need to be repaired quickly in seasonally frozen areas.
废浆是城市建设的主要副产品，其年产量正迅速增加。脱水废浆具有作为路基材料的潜力；然而，其在冻融环境中的性能，冻融环境会引发冻胀和解冻沉降，以及冻融循环对其宏观和微观性质影响的机制仍不明确，需要深入研究。本研究探讨了经历冻融循环的废浆的宏观和微观性质。我们进行了无侧限抗压强度（UCS）和三轴不固结不排水（UU）剪切试验，重点关注裂隙压实、弹性变形、塑性屈服和应变硬化阶段。结果表明，随着冻融循环次数的增加，强度和弹性模量降低，冻融循环产生的损伤程度也降低。为了揭示潜在的微观机制，我们进行了扫描电子显微镜（SEM）、X射线衍射（XRD）和压汞孔隙率测定（MIP）分析。这些试验突出了冻融循环过程中孔隙和微裂纹的演变。这些结果对于将大直径钻孔桩排出的废浆再利用作为季节性冻土地区需要快速修复的路基回填材料具有重要参考价值。
