Modulus Of Elasticity Of Subgrade Soil Formula

Bureau of reclamation usbr conducted soil tests to determine modulus of soil reaction values for a wide variety of soils having differing compaction levels.

Modulus of elasticity of subgrade soil formula. The pressure displacement response of the soil in the cbr mould is simulated using cosmosworks fem model where the soil the load plunger and the steel mould of cbr are represented. Soil elastic properties both the initial response and the long term response due to soil consolidation from the sustained loading. The measured modulus of elasticity and resilient modulus of the subgrade soils from the california bearing ratio test and unconfined cyclic triaxial test under identical moisture and density. Vertical or lateral subgrade modulus by even 300 would do little to the maximum induced shear monemt.

E elastic modulus ksi or mpa. The above values have been provided with both imperial and metric units. As with all calculations care must be taken to keep consistent units throughout. The subgrade reaction is not a fundamental soil property.

K s q δ. A guide to soil types has been provided by structx and additional information has been provided below. K s coefficient of subgrade reaction expressed in force length 2 length q pressure on the surface at the given point δ settlement at the same point. 3 the way to determine the modulus.

Against many popular opinions modulus of subgrade reaction is not an exclusive property of a soil but depends mainly on the loaded area size of the footing or mat. The soil modulus or soil stiffness more information on the modified iowa formula can be found in rinker materials info series 204. As discussed above modulus of subgrade reaction is the ratio between the contact pressure q and its corresponding settlement s. Anyway the formula as we know it is k pressure settlement.

It is a lump constant of which the subgrade reaction from the plate load test should be adjusted because the subgrade reaction is a function of. The most common and probably the safest answer to the question of correlation between bearing capacity and the modulus of subgrade reaction is that there is no correlation. Different plastic and creep characteristics of the soil. The subgrade reaction modulus is determined as the ratio between the normal stress and the settlement from 0 to 1 25mm.

This paper presents the procedure of evaluation of the modulus of elasticity e and the modulus of subgrade reaction k s value based on the california bearing ratio cbr tests and fem analysis. I always liked vesic s formulas because it included things i could understand like the elastic modulus of the soil poisson s ratio and the width of the foundation.