Identify the INCORRECT option.

SPT-N-values are correlated with:

Explanation:

NOTE: We have to find the incorrect statement from the given statements.

Standard Penetration Test: Standard penetration test can be used to determine:

• Relative density of sand
• Angle of internal friction (ϕ)
• Unconfined compressive strength of clay
• Ultimate bearing capacity on the basis of shear criteria
• Allowable bearing pressure on the basis of settlement criteria
• Load carrying capacity of pile
   

For standard penetration test:

(i) It is performed as a guideline in IS: 2131-1981 in the clean hole of 55 to 150 mm in diameter.

(ii) A thick wall split-tube sampler, 50.8 mm outer diameter and 35 mm inner diameter, is driven into the undisturbed soil at the bottom of the hole under the blows of a 65 kg drive weight with 75 cm free fall.

(iii) The minimum open length of the sampler should be 60 cm. It is first driven through 15 cm as a seating drive and is further driven through 30 cm or until 100 blows have been applied.

(iv) The number of blows required to drive the sampler 30 cm beyond the seating drive, is termed the penetration resistance N or SPT number.

The final SPT number is related to friction angle and relative density. which is given in the table