How do you determine if a soil is normally consolidated or Overconsolidated?

How do you determine if a soil is normally consolidated or Overconsolidated?

If the current effective stress, s’, is equal (note that it cannot be greater than) to the preconsolidation stress, then the deposit is said to be normally consolidated (NC). If the current effective stress is less than the preconsolidation stress, then the soil is said to be over-consolidated (OC).

What is the difference between normally consolidated soils and over consolidated soils?

Normally consolidated clays are these that are currently experiencing the maximum vertical overburden effective pressure they have ever experienced in their history. Over consolidated clays have experienced a higher overburden stress in the past.

What is an Overconsolidated clay?

over-consolidated clay Clay that has been more compacted than would be expected from the existing overburden, e.g. it has been subjected to pressure from overburden that has subsequently been removed by erosion. Compare NORMALLY CONSOLIDATED CLAY.

What is OCR in geotechnical engineering?

In geotechnical engineering, generally a parameter called the overconsolidation ratio (OCR) is used to indicate the stress history of a soil deposit. Value of OCR can be determined by conducting an odometer test using an undisturbed soil sample.

What are Overconsolidated soils?

The soil which had its load removed is considered to be “overconsolidated”. This is the case for soils that have previously had glaciers on them. The highest stress that it has been subjected to is termed the “preconsolidation stress”.

Is the clay normally consolidated or Overconsolidated?

A clay soil is said to be normally consolidated if the effective overburden pressure that it is currently experiencing is the maximum it has ever experienced in its history. Overconsolidation can occur in clays due to reasons such as; Self-weight of the soil which has eroded.

Is Overconsolidated soil stronger?

The overconsolidation ratio of a normally consolidated clay is unity, while the overconsolidation ratio of an overconsolidated soil is greater than unity.

What do you mean by Overconsolidated soil?

How do you measure soil OCR?

OCR is evaluated by the formula: OCR = σ’p / σ’yy. If OCR≤1, the soil is considered to be normally consolidated, when OCR> 1 – it is overconsolidated. POP is evaluated by the formula: POP =|σ’p-σ’yy| and is not used in the classification of soils (Fig.

Do normally consolidated soils have more strength then over consolidated soil?

Effect of over-consolidation on shear strength The normal stress of 50 kPa, peak strength was obviously larger after consolidation to 600 kPa than that after consolidationsto500 and 400 kPa.

What is normally consolidated?

A soil that is currently experiencing its highest stress is said to be “normally consolidated” and has an OCR of one. A soil could be considered “underconsolidated” or “unconsolidated” immediately after a new load is applied but before the excess pore water pressure has dissipated.

What is a normally consolidated soil?