Geotechnical Engineering

DHARM

N-GEO\OBJ.PM5 895

OBJECTIVE QUESTIONS 895

291. The two basic kinds of machines with regard to their dynamic effects on the foundation
     are: (a) ............ (b) .............


292. A simple, but common, type of foundation for a machine is .............


293. Besides avoidance of shear failure and deleterious settlements, two more important
     criteria for the design of a machine foundation are: (a) ............ (b) .............


294. There is no rational method to determine the mass of soil participating in the vibration
     of a machine foundation-soil system. True/False.


295. Calculation of ............ is an important step in the design of a reciprocating machine.


296. In the computation of the unbalanced interial forces, the first harmonic gives the ............
     inertial force, and the second and higher harmonics give ............ inertial force.


297. In a multi-cylinder engine, the crank angles play an important role in the computation
     of unbalanced intertial forces. True/False.


298. A hammer foundation is a typical example of that for ............ type machine.


299. The ratio between the relative velocity before impact to that after impact is called ............
     .


300. The model for the dynamic analysis of a hammer foundation with elastic pad has a
     degree of freedom of .............


301. Barkan’s empirical procedure for the design of a hammer foundation involves the use of
     two equations ............ one for ............ of the foundation, and the other for ............ of the
     foundation.


302. The two kinds of vibration isolation are: (a) ............ (b) .............


303. Active isolation is also known as ............ and passive isolation is known as .............


304. ............ barriers is a method of vibration isolation.


305. Three important isolating materials are: (a) ............ (b) ............ (c) .............


306. Changing the natural freuqnecy of the foundation system at a later stage after con-
     struction, if found necessary, is known as .............

NOTE

The topics in which small numercial questions may be given are the following:

1. Porosity, void ratio, Degree of Saturation, etc.


2. Unit weights–saturated, dry, submerged, moist ; Unit Phase–diagram, etc.


3. Weight–volume relationships.


4. Grain specific gravity determination ; Density index, consistency limits and indices, etc.


5. Effective and neutral stresses, permeability, permeameters, critical hydraulic gradi-
   ents, etc.


6. Seepage, computation of discharge, exit gradient from flow nets.


7. Total settlement due to consolidation, compressiblity characteristics, coefficient of con-
   solidation, Time-rate of settlement under different drainage conditions, etc.


8. Mohr-Coulomb equation, shear box test, etc.