## How do you find the resilient modulus of subgrade?

While the modulus of elasticity is stress divided by strain for a slowly applied load, resilient modulus is stress divided by strain for rapidly applied loads – like those experienced by pavements. Resilient modulus is determined using the triaxial test.

What is effective resilient modulus?

Resilient Modulus (Mr) is a fundamental material property used to characterize unbound pavement materials. It is a measure of material stiffness and provides a mean to analyze stiffness of materials under different conditions, such as moisture, density and stress level.

How do you calculate resilient modulus?

The resilient modulus can be expressed as 𝑀 𝑅 = 𝜎 𝜀 𝑟 , ( 1 ) where 𝜎 is the applied stress and 𝜀 𝑟 is the recoverable axial strain.

### Which test is carried to determine the resilient modulus of a subgrade soil?

It is known that a laboratory resilient modus test and a falling weight deflectometer (FWD) test are usually used to obtain the resilient modulus of subgrade [5, 6].

What is a 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 modulus toughness?

Modulus of toughness is the ability of a material to absorb energy in plastic deformation. It is defined as the amount of strain energy density (strain on a unit volume of material) that a given material can absorb before it fractures. Modulus of toughness is measured in units of PSI or Pascals.

The Subgrade Modulus, also known as the Modulus of Subgrade Reaction, is a stiffness parameter typically used in defining the support conditions of footings and mat foundations, such as that shown on Figure 1. The parameter is expressed in units of [Force]/[Length]3. Mat foundation for a building under construction.

What is the difference between elastic modulus and resilient modulus?

Elastic modulus is a measure of material stiffness and is defined as the slope of the stress-strain curve of a given material within its linear elastic region. Resilient modulus is an estimate of the elastic modulus based on recoverable strain under repeated loading.

What is dynamic modulus of elasticity?

Dynamic modulus (sometimes complex modulus) is the ratio of stress to strain under vibratory conditions (calculated from data obtained from either free or forced vibration tests, in shear, compression, or elongation). It is a property of viscoelastic materials.