Geotechnical Engineering

DHARM

N-GEO\OBJ.PM5 894

894 GEOTECHNICAL ENGINEERING

266. The resistance to motion in a physical system is known as .............


267. The internal loss of energy by absorption in a stressed system undergoing vibration is
     called ............ damping.


268. The damping effect caused by the dissipation of energy by wave propogation in a soil
     mass is called ............ damping.


269. If the amplitude of a system continues to increase as the system is supplied energy from
     an external source, it is said to be ............ damped.


270. The time-displacement relationship is shown by means of a ............ curve.


271. ‘Frequency ratio’ is defined as the ratio of .............


272. The ratio of the dynamic amplitude to static displacement is called the .............


273. The limiting value of the damping coefficient for the motion to be periodic is the ............
     .


274. The ratio of the damping coefficient in a given case to the critical damping coefficient is
     called .............


275. The natural logarithm of the ratio of any two successive amplitudes of the same sign in
     the decay curve in a free vibration with damping is known as the .............


276. The two kinds of excitation are: (a) ............ (b) .............


277. The type of excitation caused by the rotation of unbalanced masses is constant-force
     amplitude excitation. True/False.


278. The type of excitation caused by an electromagnetic vibration is ............ excitation.


279. The engineering behaviour of a soil is unaffected by the application of dynamic loading.
     True/False.


280. Mass of the soil participating in the vibration should be included in the computation of
     the ............ of a machine foundation soils system.


281. The two broad approaches used to analyse a machine foundation soil system undergo-
     ing vibrations are: (a) ............ (b) .............


282. ............ and ............ are the parameters required in the analysis using mass-spring-
     dashpot model.


283. ............ and ............ are the parameters required in analysis using the elastic half-space
     theory.


284. The two basic types of a elastic waves are: (a) ............ (b) .............


285. P-waves and S-waves are the two modes of surface waves. True/False.


286. Body waves are categorized into two modes: (a) ............ (b) .............


287. A repeated plate bearing test is used to determine the ............ of the soil.


288. The product of the coefficient of elastic uniform compression and the horizontal contact
     area between the foundation and the soil gives the ............ of the soil.


289. The test used for the determination of in-situ dynamic properties of soil is ............ of a
     cement concrete block.


290. The coefficient of elastic uniform compression is inversely related to ............ of the
     foundation.