Studies on the Engineering Characteristics of Alluvial Clayey Deposits in the Bay Area of Asan (II)

아산만지역 충적점토의 토질특성에 관한 연구(II)

  • Published : 1988.06.01

Abstract

This study was conducted to investigate the various engineering properties and correlationshops among the soil constants of alluvial clayey deposits distributed in the bay of Asan and their results are summarized as follows : 1. Grain size distribution of soil was consisted of 12 % of clay, 46-73 % of silt, 2-23 % of sand, and as for the consistency characteristics, 26-36 % of liquid limit, 18-21 % of plastic limit and 6-16 % of plastic index, and so the soil belonging to as a lower plastic nonorganic clay, it's specific gravity was 2,66-2.70, and the location on the plastic chart was approximately above the A-line. Z The natural moisture content and unit weight were 30-43 % and 1.76-1.87 g I cm$_3$, respectively, and according to increment of natural moisture content, the unit weight was decreased, and the initial void ratio and degree of saturation were shown of 0,87-1119 and 92- 100 %, most of saturated. 3. Cone resistance value which was shown 2.4 - 6.5 kg / $cm^2$ was a little lower and it was increased with the depth of layer and shown the formular $q_c=0.7_z+1.32$. 4. Unconfined compression strength was about 0.18-0.43kg /$cm^2$, cu, 0.1-0.22kg / $\psi$, $2-6^{\circ}$ under uu-test condition of triaxial, and CCU, 0.08-0.3 kg/cm , $\psi$, $12-18^{\circ}$ under the condition of cu-test. 5. Pre-consolidation load of characteristics of consolidation was 0.4-0.8 kg / $cm^2$, compression index, about 0.17-0.33. 6. Liquid limit and plastic index were incresased with the increment of clay content but most of alluvial clay was appeared as a normal through non-activity clay soil shown more natural moisture content than liquid limit, and their relationship as follows : LL=0.38( cy+54.8), PI=0.836(LL -17.8), PI =0.468(LL -0.48) 7. The initial void ratio presented correlationship of positive among clay content, natural moisture content and liquid limit, and that of reverse with unit weight, and their results as follws : $e_o=0.024(w_n+0.2)$, $e_o=e_o=0.0003c_y+0.0005 LL+0.0151 W_n+\frac{3.58}{r-t}-1.52$ 8. It was shown that the compression index has correlationship of postive among the clay content, liquid limit, plastic index, natural moisture content and initial void ratio, and their relationships as follows ; $c_c=0.44(e_o-0.47)$, $c_c=0.001$

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