Spanish Edition 3. Figure 4.2 Plasticity chart G w.GM op.oM G POC sw.SM sw.sC with day Sill y Silt' (or (ReÞinted with ASTM ASTM PA. 50 50 4.4 The Unified Soil Classification System is based on the airfield soil classification system developed by Casagrande during World War II. Performing Tests and Obtaining Descriptive Information The USCS groups soils according to potential engineering behavior. Soil Classification Chapter 4 AASHTO. However, it alone does not provide adequate descriptive terminology and … It is used in the U.S. and much UNIFIED SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP SYMBOLS TYPICAL NAMES I COARSE GRAINED SOILS (More than 50% of material is LARGER than No. Determining the Unified Soil Classification System (USCS) Symbol and Group Name with Modifier using lab data (ASTM D2487) A rough correlation between these three classification systems is provided at the end of this section. All soil classification descriptions for particle sizes less than No. * To use this chart, start on the top and work your way down using the steps to guide you to the appropriate USCS Symbol, Group Name, and Modifier. 4.2 The soil can be given an identification by assigning a group symbol(s) and name.The flow charts, Fig. Is soil highly organic, coarse grained, or fine grained? USCS: TEST NUMBER: P13: TEST METHOD TYPE: B: VERSION NUMBER: 2: SCOPE: This test method describes the engineering properties of a soil based on the size of the particles, the amounts of the various sizes and the characteristics of the very fine grains. Coarse Grained Run sieve analysis Gravel (G) Less than 5% pass No. It became known as the Unified Soil Classification System when several U.S. Government Agencies adopted a modified version of the Airfield System in 1952. Unified soil classification system is adopted by ASTM D-2487-98 and IS: 1498-1970 for classification and identification of soils for general engineering purpose. It can 200 sieve size) FINE GRAINED SOILS (More thon 50% of material is SMALLER than No. CEA – Lesson 3.4 – USCS Soil Classification Chart Visual Examination. For classification, a clay is a fine-grained soil, or the fine-grained portion of a soil, with a Contents:Unified Soil Classification System1. UNIFIED SOIL CLASSIFICATION SYSTEM Name Group Symbols LABORATORY CRITERIA Fines (%) Grading Plasticity Notes coarse grained (more than 50% larger than 63 μm BS or No.200 US sieve size (0.074 mm)) Gravels (more than 50% of coarse fraction of gravel size) Well graded gravels, with little or no fines GW 0-5 C u >4 1