Geotechnical Engineering

DHARM

N-GEO\OBJ.PM5 887

OBJECTIVE QUESTIONS 887

114. The degree of compaction of a soil is characterized by its .............


115. The higher the compactive effort, the ............ the optimum moisture content upto a
     limit.


116. Irrespective of the compactive effort, a soil cannot reach the zero-air-voids condition.
     True/False


117. The higher the compactive effort, the ............ the maximum dry density upto a limit.


118. Sheepsfoot roller is unsuitable for compacting granular soils. True/False


119. The best method for the compaction of cohesionless soils is .............


120. Relative or degree of compaction means .............


121. Proctor Plasticity needle is useful for quick determination of

(a) insitu dry unit weight.

(b) insitu moisture content.

(c) both insitu dry unit weight and in situ moisture content.

(d) optimum moisture content and maximum dry density.

122. The soil involved in compaction is always partly saturated. True/False.


123. ............ movement is required to mobilize full active pressure; however, ............ move-
     ment may be required for the mobilization of full passive resistance.


124. According to the theory of elasticity, the coefficient of earth pressure at rest, Ko, is given
     by Ko = .............


125. Wall friction ............ the active earth pressure on a wall and ............ the passive earth
     resistance of the soil.


126. Uniform Surcharge increases the active earth pressure while it decreases the passive
     resistance. True/False.


127. Cohesion

(a) increases the active pressure and decreases the passive resistance.

(b) decreases both active pressure and passive resistance.

(c) increases both active pressure and passive resistance.

(d) decreases active pressure and increases passive resistance.

128. The passive pressure coefficient for an inclined backfill of dry sand is the reciprocal of
     active pressure coefficient according to Rankine’s theory. True/False


129. The critical depth or the unsupported height to which a pure clay soil will be stable is
     given by Hc = .............


130. Coulomb’s simplyfying assumption that the failure surface is a plane instead of a curved
     one introduces significant error in the computation of ............. In fact, it ............ the
     value.


131. The average angle of wall friction, δ, in terms of φ, is given as ............, according to
     Terzaghi.


132. Coulomb’s theory does not satisfy the static equilibrium condition. True/False


133. Wall friction can never be negative. True/False