# What is modulus of subgrade reaction of soil?

## What is modulus of subgrade reaction of soil?

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 K value of 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.

What is meant by subgrade modulus?

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 KS soil?

Again, the definition of Ks is the pressure per unit settlement. In other words, soil capacity to withstand pressure for a given displacement. From earlier discussions, it is also clear that even bearing capacity has an allowable settlement.

What is coefficient of subgrade reaction?

Hi, In simple words coefficient of subgrade reaction is the function of stiffness and compressibility of soil. It is also known as Modulus of subgrade reaction. It is pressure sustain by a sample of soil under a rigid plate of std diameter/unit settlement measured at a specified pressure.

What is modulus of subgrade reaction and resilient modulus?

The resilient modulus of pavement subgrade is an essential parameter for mechanistically based pavement design procedures; the modulus of subgrade reaction (k) is used as a primary parameter for rigid pavement design.

## What is the formula to find the value of k if a plate of diameter 30 cm is used instead of the standard 75cm?

in some cases, smaller diameter plates can be used. But these have to be converted to standard values, k75=0.5×k30 gives the relation for the same.

What is soil stiffness?

In general, soil stiffness is determined by soil shear strength. The higher the soil stiffness is, the more fatigue damage may occur in the riser pipe, since vibration frequency and stress ranges will be higher. Secant soil stiffness is generally higher than tangent soil stiffness.

What is soil modulus?

in Parameters. 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.

### What is the resilient modulus?

The resilient modulus is defined as the ratio of the applied cyclic stress to the recoverable (elastic) strain after many cycles of repeated loading (Figure 5-14) and thus is a direct measure of stiffness for unbound materials in pavement systems.

What is the CBR of sub-base?

The minimum CBR value of a sub-base soil should be 20% and 30% for traffic up to 2 msa and traffic exceeding 2 msa respectively.

How do you calculate subgrade modulus?

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 stiffness 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’ is the modulus or coefficient of subgrade reaction, ‘p’ is the pressure, and ‘s’ is the deformation of soil settlement.