What is a good modulus of subgrade reaction?
Relation of load, deflection and modulus of subgrade reaction (k). The value of k is in terms of MPa/m (pounds per square inch per inch of deflection, or pounds per cubic inch – pci) and ranges from about 13.5 MPa/m (50 pci) for weak support, to over 270 MPa/m (1000 pci) for strong support.
What is the subgrade modulus of soil?
The subgrade modulus is a function of the soil stiffness and compressible layer thickness, as well as the foundation dimensions and stiffness. The subgrade modulus is not constant underneath a foundation.
What is K value for soil?
K factor is soil erodibility factor which represents both susceptibility of soil to erosion and the rate of runoff, as measured under the standard unit plot condition. Soils high in clay have low K values, about 0.05 to 0.15, because they resistant to detachment.
How do you find the modulus of a subgrade reaction?
What is modulus of subgrade reaction? Modulus of subgrade reaction is defined as the pressure per unit deformation of the subgrade at specific pressure or deformation. It is expressed as k=p/s. Here, k = modulus or coefficient of subgrade reaction; p = applied pressure and s = deformation of soil settlement.
What is subgrade modulus in safe?
The modulus of subgrade reaction ks is a function of the contact pressure and allowable settlement on an unit area of soil. It is also known as Pressure per unit settlement. On the other hand, the safe bearing capacity is the maximum pressure which the soil can carry safely without risk of shear failure.
What is Ev2 test for soil?
Ev2 Plate Bearing Test Set Static Deformation Testing Machine USAGE OVERVIEW:Ev2 Plate bearing test set is used to measure the settlement value of Subgrade under static load, so as to evaluate the bearing capacity and deformation of subgrade.
How do you calculate subgrade modulus from soil bearing capacity?
k = 40 x SF x qa, where SF is factor of safety considered in bearing pressure calculation and qa is allowable soil bearing capacity. So, you could employ the above equation in determining the Soil Subgrade Modulus.
What is highly erodible soil?
Highly erodible soils are those soils that have a potential to erode at a rate far greater than what is considered tolerable soil loss.
What is subgrade modulus in staad?
Subgrade modulus has units of force per length^3. So, the spring will have units of force/length. The problem with using this method is that, for irregularly-shaped or large slabs with. many nodes, computing the influence area for each node can become quite tedious.
How do you calculate the modulus of subgrade reaction from safe bearing capacity of soil?
What is soil modulus?
Soil Young’s modulus (E), commonly reffred to as soil elastic modulus, is an elastic soil parameter and a measure of soil stiffness. It is defined as the ratio of the stress along an axis over the strain along that axis in the range of elastic soil behaviour.