Tag Archive for Tag: Sand

Tag: Sand Safe Bearing Pressures for Mat Foundations on Sand and Clay

Mats on Sand Because the differential settlements of a mat foundation are less than those of a spread foundation designed for the same soil pressure, it is reasonable to permit larger safe soil pressures on a raft foundation. Experience has shown that a pressure approximately twice as great as that allowed for individual footings may be used because it does

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Tag: Sand Coulomb’s Earth Pressure Theory for Sand for Passive State

PASSIVE STATE In Fig. 11.18, the notations used are the same as in Fig. 11.17. As the wall moves into the backfill, the soil tries to move up on the pressure surface AB which is resisted by friction of the surface. Shearing stress on this surface therefore acts downward. The passive earth pressure P is the resultant of the normal

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Tag: Sand Coulomb’s Earth Pressure Theory for Sand for Active State

Coulomb made the following assumptions in the development of his theory: 1. The soil is isotropic and homogeneous 2. The rupture surface is a plane surface 3. The failure wedge is a rigid body 4. The pressure surface is a plane surface 5. There is wall friction on the pressure surface 6. Failure is two-dimensional and 7. The soil is

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Tag: Sand The Unified Soil Classification System (USCS)

The Unified Soil Classification System is based on the airfield classification system developed by A. Casagrande during World War II. With some modification it was jointly adopted by several U.S. government agencies in 1952. Additional refinements were made and it is currently standardized as ASTM D 2487-93. It is used in the U.S. and much of the world for geotechnical

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Tag: Sand Sand

Sand is a natural product which is obtained as river sand, nalla sand and pit sand. However sea sand should not be used for the following reasons: 1. It contains salt and hence structure will remain damp. The mortar is affected by efflorenscence and blisters appear. 2. It contains shells and other organic matter, which decompose after some time, reducing

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