In the case of well foundation, the Indian Standard code recommends that tilt and shift of well should respectively be

Explanation:

Shifting and tilting of well foundation:

• When the well is moved away horizontally from the desired position, it is called shifting of the well foundation.
• When the well is sloped against vertical alignment, it is called tilting of the well foundation.

Prevent shifting and tilting:

• The diameter of well curb should be more than the external diameter of steining. Generally, a difference of 40 to 80 mm is recommended.
• The well steining should be symmetrically placed over the curb.
• The outer surface of the well curb and steining should be smooth.
• All the sides should be uniformly dredged.
• The cutting edge should be uniformly thick and sharp.

Limitations:

• The maximum tilt allowed in case of well foundation is 1 in 60.
• The shift in well foundation should not be more than 1 % of depth of sunk.
• Beyond the above limits, well foundation is considered as dangerous and in such a case, remedial measures to rectify shifting and tilting should be followed.