[...]... SHEAR STRENGTH OF SOILS 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 7.11 7.12 7.13 7.14 7.15 7.16 7.17 7.18 7.19 Introduction Mohr–Coulomb failure criteria Shearing strength of granular soils Critical void ratio Curvature of the failure envelope General comments on the friction angle of granular soils Shear strength of granular soils under plane strain condition Shear strength of cohesive soils Unconfined... process of this book Braja M Das Chapter 1 Soil aggregate, plasticity, and classification 1.1 Introduction Soils are aggregates of mineral particles, and together with air and/or water in the void spaces, they form three-phase systems A large portion of the earth’s surface is covered by soils, and they are widely used as construction and foundation materials Soil mechanics is the branch of engineering... “Consolidation,” “Shear strength of soils,” and “Settlement of foundations.” This chapter is a brief overview of some soil properties and their classification It is assumed that the reader has been previously exposed to a basic soil mechanics course 1.2 Soil separate size limits A naturally occurring soil sample may have particles of various sizes Over the years, various agencies have tried to develop the size... deals with the engineering properties of soils and their behavior under stress This book is divided into eight chapters— Soil aggregate, plasticity, and classification,” “Stresses and strains—elastic equilibrium,” “Stresses and displacement in a soil mass,” “Pore water pressure due to undrained loading,” “Permeability and seepage,” “Consolidation,” “Shear strength of soils,” and “Settlement of foundations.”... plasticity index and percentage of clay-size fraction by weight Grain-size distribution of a sandy soil Weight–volume relationships for soil aggregate Weight–volume relationship for Vs = 1 Weight–volume relation for saturated soil with Vs = 1 Weight–volume relationship for V = 1 Weight–volume relationship for saturated soil with V = 1 Youd’s recommended variation of emax and emin with angularity and Cu Variation... are examples of some clay minerals 2 Soil aggregate, plasticity, and classification Table 1.1 Soil separate size limits Agency Classification Size limits (mm) U.S Department of Agriculture (USDA) Gravel Very coarse sand Coarse sand Medium sand Fine sand Very fine sand Silt Clay >2 2–1 1–0.5 0.5–0.25 0.25–0.1 0.1–0.05 0.05–0.002 < 0 002 International Society of Soil Mechanics (ISSS) Gravel Coarse sand... values of PI + CF Directional variation of coefficient of permeability Directional variation of permeability Variation of kv and kh for Masa-do soil compacted in the laboratory Flow in horizontal direction in stratified soil Flow in vertical direction in stratified soil Variations of moisture content and grain size across thick-layer varves of New Liskeard varved clay Determination of coefficient of permeability... One-directional flow through two layers of soil Flow net around a single row of sheet pile structures Flow net under a dam Flow net under a dam with a toe filter Flow through a flow channel Pressure head under the dam section shown in Figure 5.27 Construction of flow net under a dam Flow net construction in anisotropic soil Transfer condition Flow channel at the boundary between two soils with different coefficients... values of and c for granular soils and c 7.2 Experimental values of 7.3 Consistency and unconfined compression strength of clays 7.4 Relative values of drained friction angle 7.5 Empirical equations related to Su and p 7.6 Values of F for some soils 7.7 Ratio of ab to ae1 7.8 Results of Kirkpatrick’s hollow cylinder test on a sand 8.1 General range of Poisson’s ratio for granular soils 8.2 Values of from... flocculation of clay in a suspension a Dispersion and b flocculation of clay a Salt and b nonsalt flocculation of clay particles Consistency of cohesive soils Schematic diagram of a liquid limit device, b grooving tool, c soil pat at the beginning of the test and d soil pat at the end of the test Flow curve for determination of liquid limit for a silty clay 3 4 5 6 7 8 8 9 10 11 13 13 14 14 15 16 16 17 18 19 .