International Journal of Highway Engineering (한국도로학회논문집)

Korean Society of Road Engineers (한국도로학회)
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Experimental Study on Road-Subsidence Characteristics in Unsaturated Sandy Soils

불포화 사질토의 도로함몰 특성에 관한 실험적 연구

  • Received : 2017.10.24
  • Accepted : 2018.01.29
  • Published : 2018.02.19
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Abstract

PURPOSES : The purpose of this study is to identify the road-subsidence mechanism in unsaturated sandy soils. METHODS : A series of soil chamber tests were conducted under various conditions. RESULTS : The cavity-expansion characteristics in unsaturated sandy soils due to seepage were affected by the outlet size, seepage intensity, relative density, and fine content. CONCLUSIONS : In unsaturated sandy soils, the cavity-expansion speed was affected by the outlet size, relative density, seepage intensity, and clay content; however, the cavity-expansion shape was very similar. As the outlet size and seepage intensity increased, the cavity-expansion speed increased. As the relative density increased, the cavity-expansion speed increased because of a sudden decrease in shear strength, resulting from the increased saturation (reduction of matric suction). The cavity expanded faster with the increasing clay content, up to a certain threshold. It expanded at a slower rate once it passed the threshold. Finally, it reached a stable state where the cavity did not expand due to seepage.

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