What is the full name and acronym for the soil classification system used predominately in this course? To be effective, a compacted soil liner should have low hydraulic conductivity, which in many cases is considered to be less than 1 “ 10 -7 cm/s. Unified Soil Classification System (USCS)Coarse-Grained Soil Classification. Recommendations for Using Soil Classification Data.

Differences in plasticity of clays are reflected by the plasticity index. Briefly explain why it is important to have a standard 5.1 The hydraulic conductivity function (HCF) is fundamental to hydrological characterization of unsaturated soils and is required for most analyses of water movement in unsaturated soils. Questions (2 Points Each - 20 Points Total): 1. What is the Questions (2 Points Each - 20 Points Total): 1.

There is a dearth of test data about the effects of plant roots on the SHCF ().Jotisankasa & Sirirattanachat (2017) show that root effects on hydraulic conductivity were prominent only when matric suction of the soil was less than 10 kPa, whereas the hydraulic conductivity measured by Song et al. Unified Soil Classification System (USCS) Separates soils into two broad categories and then uses a flow-chart approach to classify based on soil properties (%’s by weight) At the same liquid limit, the higher the plasticity index, the more cohesive the clay. 14.330 SOIL MECHANICS Exam #1: Soil Composition, Soil Classification, Soil Compaction, Hydraulic Conductivity, and Soil Stresses. You are given the following results from Atterberg Limits testing on a soil sample (wp = 23%, wL = 50%) collected from a boring on a local project site. Between 5 and 15% ... 2nd symbol (SC) identifies the type of fines (silt or clay) Hydraulic conductivity significance (fines lower K by reducing effective porosity) + other soil properties. The classification system can be applied to most unconsolidated materials, and is represented by a two-letter symbol.

For instance, the HCF is a critical parameter to analyze the movement of water during infiltration or evaporation from soil specimens. Marcel G. Schaap, Feike J. Leij, Improved Prediction of Unsaturated Hydraulic Conductivity with the Mualem‐van Genuchten Model, Soil Science Society of America Journal, 10.2136/sssaj2000.643843x, 64, 3, (843-851), (2000). You are given the following results from Atterberg Limits testing on a soil sample (wp = 23%, wL = 50%) collected from a boring on a local project site.

5.1 The hydraulic conductivity function (HCF) is fundamental to hydrological characterization of unsaturated soils and is required for most analyses of water movement in unsaturated soils. 14.330 SOIL MECHANICS Exam #1: Soil Composition, Soil Classification, Soil Compaction, Hydraulic Conductivity, and Soil Stresses. Unified Soil Classification System • Classify soil for use in engineering and geology • Two-letter symbol • Tested “out of place” 1. The Unified Soil Classification System (USCS) is a soil classification system used in engineering and geology to describe the texture and grain size of a soil. 14.330 SOIL MECHANICS Exam #1: Soil Composition, Soil Classification, Soil Compaction, Hydraulic Conductivity, and Soil Stresses. The conclusions that can be drawn from this study are: (1) The area of soil testing for hydraulic conductivity overlaps several professions: geology, hydrology, soil engineering, and soil science; (2) Most testing methods for hydraulic conductivity have been developed for agricultural or engineering purposes other than application to the feasibility and design of solid or hazardous waste disposal … In some cases, saturated hydraulic conductivity (a quantitative- Questions (2 Points Each - 20 Points Total): 1. Plasticity/Liquid Limit 3. For simplicity, either case is considered im-permeable for hydrologic soil group purposes.

Table 2 Soil Separate Size Limits Classification system Grain size (mm) Unified Gravel: 75 mm to 4.75 mm Sand: 4.75 mm to 0.075 mm Silt and clay (fines): < 0.075 mm AASHTO Gravel: 75 mm to 2 mm Sand: 2 mm to 0.05 mm Silt: 0.05 mm to 0.002 mm Clay: < 0.002 mm