## What is effective stress in soil?

Effective stress can be defined as the stress that keeps particles together. In soil, it is the combined effect of pore water pressure and total stress that keeps it together. It can also be defined in equation form as the total stress minus the pore pressure.

**What is total stress?**

Total stress at a point is defined as the sum of the stress exerted by the total weight (solids plus water) of the soil/rock and the load on the foundation.

### What is Geostatic step in Abaqus?

Generally, geostatic step is used to establish in-situ stresses in soil profile concurrent with no deformation which is the case for most of the geotechnical problems. You can use static general step under gravity loading but you will have some degree of deformation under this load.

**What is Isobar soil?**

An isobar or pressure bulb is a stress contour or a line which connects all points below the ground surface at which the vertical pressure is the same.

#### What are principles of effective stress?

Effective stresses affect a number of properties, including volume change, shearing strength, permeability and compressibility. To summarise, the efficient stress theory is as follows : Total stress minus pore pressure equals effective stress. The shearing strength of soil is regulated by effective stress.

**How do you measure effective stress in the soil?**

The total stress is the sum of the weight of the soil up to the surface and the weight of water above this: Vertical total stress at depth z, sv = g . z + gw . z.

## What is neutral stress?

The stress transmitted by the fluid that fills the voids between particles of a soil or rock mass; e.g., that part of the total normal stress in a saturated soil caused by the presence of interstitial water. Synonym of: pore pressure, pore-water pressure, neutral pressure. Ref: AGI.

**What is horizontal stress?**

The horizontal stress is customarily expressed as a proportion of the vertical stress σH = K’o σv = K’o ρd gz (3.2) where K’o = coefficient of earth pressure at rest in terms of effective stresses (see equation (3.7)).

### What is stress isobar?

An isobar or pressure bulb is a stress contour or a line which connects all points below the ground surface at which the vertical pressure is the same. Thus, the stress isobar is also called the ‘bulb of pressure’ or simply the ‘pressure bulb’. The vertical pressure at each point on the pressure bulb is the same.

**What does isobar and pressure bulb mean?**

Answer: Isobar is a curve joining points in soil which experience equal stress intensity due to the application of load on the soil. Pressure bulb denotes the area in a soil where load has a significant effect on settlements caused.