Scholarlink

Abstract <p>The pronounced swell-shrinkage characteristics of expansive soil constitute the primary causative factor for engineering hazards in expansive soil regions. The application of ecological improvement methods to mitigate the swell-shrinkage properties demonstrates promising application prospects. This research applies environmentally friendly materials—biochar and sisal fiber—to synergistically improve expansive soil. Through systematic testing of swelling ratio and shrinkage ratio indices of the amended soil, the influence patterns of these two materials on the expansibility and swell-shrinkage characteristics of expansive soil were revealed. The improvement mechanism was further elucidated through scanning electron microscopy (SEM) test. Experimental studies have demonstrated that individual incorporation of biochar or sisal fiber can effectively inhibit the swell-shrinkage characteristics of expansive soil, while the combined incorporation exhibits a more pronounced inhibitory effect compared to individual treatments. Specifically, the swelling ratio under 50 kPa load of expansive soil incorporated with 8% biochar and 0.15% sisal fiber (20 mm length) showed a 95.7% reduction compared to original expansive soil. Furthermore, the linear shrinkage ratio of soil modified with 8% biochar and 0.6% sisal fiber (20 mm length) demonstrated a 56.3% decrease relative to the original expansive soil. The most influential factor affecting the swelling ratio of amended soil was identified as the biochar dosage, while the sisal fiber dosage exhibited the predominant effect on the shrinkage ratio. Microstructural analysis revealed that biochar particles effectively absorbed moisture through their porous structure while providing structural support to soil particles, whereas sisal fiber dissipated stress via their three-dimensional network configuration. The synergistic interaction between these two additives demonstrated remarkable suppression of the expansive soil’s swell-shrinkage characteristics.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Research on Swell-Shrinkage Behavior and Microscopic Mechanism of Expansive Soil Improved Synergistically by Biochar and Sisal Fiber

  • 期刊论文

  • 发表日期：

    2025年12月18日

查看全文
  • A. J. Chen,
  • Z. Y. Chen,
  • J. H. Chen,
  • X. Shi,
  • Y. P. Liu

摘要

Abstract

The pronounced swell-shrinkage characteristics of expansive soil constitute the primary causative factor for engineering hazards in expansive soil regions. The application of ecological improvement methods to mitigate the swell-shrinkage properties demonstrates promising application prospects. This research applies environmentally friendly materials—biochar and sisal fiber—to synergistically improve expansive soil. Through systematic testing of swelling ratio and shrinkage ratio indices of the amended soil, the influence patterns of these two materials on the expansibility and swell-shrinkage characteristics of expansive soil were revealed. The improvement mechanism was further elucidated through scanning electron microscopy (SEM) test. Experimental studies have demonstrated that individual incorporation of biochar or sisal fiber can effectively inhibit the swell-shrinkage characteristics of expansive soil, while the combined incorporation exhibits a more pronounced inhibitory effect compared to individual treatments. Specifically, the swelling ratio under 50 kPa load of expansive soil incorporated with 8% biochar and 0.15% sisal fiber (20 mm length) showed a 95.7% reduction compared to original expansive soil. Furthermore, the linear shrinkage ratio of soil modified with 8% biochar and 0.6% sisal fiber (20 mm length) demonstrated a 56.3% decrease relative to the original expansive soil. The most influential factor affecting the swelling ratio of amended soil was identified as the biochar dosage, while the sisal fiber dosage exhibited the predominant effect on the shrinkage ratio. Microstructural analysis revealed that biochar particles effectively absorbed moisture through their porous structure while providing structural support to soil particles, whereas sisal fiber dissipated stress via their three-dimensional network configuration. The synergistic interaction between these two additives demonstrated remarkable suppression of the expansive soil’s swell-shrinkage characteristics.