<p>In the construction of permeable roads in collapsible loess regions, a critical technical conflict exists between the water permeability requirement of road surfaces for sponge city development and the collapsibility of loess. Traditional pavement treatments impair permeability or trigger loads worsening loess collapse. Low-density, permeable and high-bearing lightweight soil suits pedestrian and non-motor roads. Based on the mechanism of loess collapsibility, this study proposes a novel foundation treatment approach: lightweight soil replacement is adopted to reduce self-weight stress and overburden pressure, thereby mitigating the collapsibility of subgrades for pedestrian and non-motor vehicle roads. The effectiveness of this treatment method is validated via multi-stratum centrifugal model tests. The research indicates that the regional correction coefficient <i>β</i><sub>0</sub> value obtained from the field immersion test was 1.56, whereas the corresponding <i>β</i><sub>0</sub> value obtained from the multi-stratum centrifugal model test was 1.78, with a discrepancy of 0.22 between the two values. It is verified that the multi-stratigraphic centrifugal model test method can be used to obtain consistent results with the field immersion test, while possessing the distinct advantages of low cost and short test duration. Following 1.5&#xa0;m of soil replacement, the site collapse value under overburden pressure was calculated to decrease by 22.73% based on laboratory tests, whereas the collapse value under overburden pressure measured by the centrifugal model test was reduced by 23.04%. These results demonstrate that lightweight soil replacement method can effectively reduce the site collapsibility. Field immersion test and the multi-stratigraphic centrifugal model test were conducted on self-weight collapsible loess in the Weicheng District of Xianyang City. The regional correction coefficient <i>β</i><sub>0</sub> was determined, ranging from 1.56 to 1.78. This empirically derived range is more representative of the site conditions in the northern loess tableland of Xianyang than the value of 0.90 specified in the current standard for loess engineering in the Guanzhong region. Therefore, it provides a technically justified basis for selecting <i>β</i><sub>0</sub> in high-grade loess plains across Guanzhong region in Shaanxi Province, China.</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

Lightweight soil replacement for reducing the collapsibility of loess in permeable sponge-city roads: insights from multi-stratum centrifuge model tests

  • Wen-jing Mi,
  • Ai-jun Zhang,
  • Zhi-chao Liang,
  • Sha Li,
  • Guo-dong Liu

摘要

In the construction of permeable roads in collapsible loess regions, a critical technical conflict exists between the water permeability requirement of road surfaces for sponge city development and the collapsibility of loess. Traditional pavement treatments impair permeability or trigger loads worsening loess collapse. Low-density, permeable and high-bearing lightweight soil suits pedestrian and non-motor roads. Based on the mechanism of loess collapsibility, this study proposes a novel foundation treatment approach: lightweight soil replacement is adopted to reduce self-weight stress and overburden pressure, thereby mitigating the collapsibility of subgrades for pedestrian and non-motor vehicle roads. The effectiveness of this treatment method is validated via multi-stratum centrifugal model tests. The research indicates that the regional correction coefficient β0 value obtained from the field immersion test was 1.56, whereas the corresponding β0 value obtained from the multi-stratum centrifugal model test was 1.78, with a discrepancy of 0.22 between the two values. It is verified that the multi-stratigraphic centrifugal model test method can be used to obtain consistent results with the field immersion test, while possessing the distinct advantages of low cost and short test duration. Following 1.5 m of soil replacement, the site collapse value under overburden pressure was calculated to decrease by 22.73% based on laboratory tests, whereas the collapse value under overburden pressure measured by the centrifugal model test was reduced by 23.04%. These results demonstrate that lightweight soil replacement method can effectively reduce the site collapsibility. Field immersion test and the multi-stratigraphic centrifugal model test were conducted on self-weight collapsible loess in the Weicheng District of Xianyang City. The regional correction coefficient β0 was determined, ranging from 1.56 to 1.78. This empirically derived range is more representative of the site conditions in the northern loess tableland of Xianyang than the value of 0.90 specified in the current standard for loess engineering in the Guanzhong region. Therefore, it provides a technically justified basis for selecting β0 in high-grade loess plains across Guanzhong region in Shaanxi Province, China.