EVALUATION METHOD FOR DETERMINING POTENTIAL RISKS OF DETECTED UNDERGROUND CAVITIES BY USING SOIL PROPERTIES

DOI Web Site 13 References
  • SATO Mari
    島根大学 学術研究院環境システム科学系
  • UNO Yoshinori
    応用地質株式会社 事業部統轄本部
  • ITO Ryota
    応用地質株式会社 社会インフラ事業部

Bibliographic Information

Other Title
  • 路床土の特性による地中空洞の陥没危険度評価指標の提案

Abstract

<p> Sinkhole accidents on urban roads are induced by the collapse of an underground cavity that expands mainly because of the soil drainage from the cracks of sewer pipes. Although ground-penetrating radar is broadly utilized for detecting cavities, an evaluation method for determining whether the detected cavity exhibits risks of eventually causing sinkholes has not been established to date. In this study, small modelscale experiments were conducted to simulate cavity expansion. The tested materials exhibited grain size distributions that were similar to those of the backfill soils, which are typically used in practical sites. Two conditions were varied: the fines content of the materials and width of the aperture, which opens at the bottom of the soil chamber for simulating cracks in sewer pipes. Experimental results indicated that the cavity collapse and approaching the surface can be evaluated by 10% or 20% grain size related to the permeability, and that cavity size enlargement can be evaluated by 85% grain size, which determines the minimum width of the cracks that lead to continuous soil drainage without clogging. Finally, an evaluation method is proposed based on the aforementioned factors and other common material properties, such as weathering potentials or soil improvement that affect the cavity growth.</p>

Journal

References(13)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top