UNIT –I :PART-A

1. Define Earth QuakeAn earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves.

2. Define Focus and EpicentreThe focus of an earthquake is the point beneath Earth's surface where rock breaks under stress and the plates shift and that is what causes the earthquake.The epicenter is the point on the Earth's surface that is directly above the hypocenter or focus, the point where an earthquake or underground explosion originates.

3. What are the different types of seismic waves?There are many types of seismic waves, body wave, surface waves, S waves and P waves

4. What are the causes of earthquake?that earthquakes are caused by faulting, a sudden lateral or vertical movement of rock along a rupture (break) surface.

5. What is the difference between magnitude and intensity?Magnitude is a measure of earthquake size and remains unchanged with distance from the earthquake. Intensity, however, describes the degree of shaking caused by an earthquake at a given place and decreases with distance from the earthquake epicenter.

6. What do you mean by intensity of an earthquake?Intensity describes the perceived surface ground shaking and damage caused by an earthquake. It is also derived based on ground accelerations as measured by seismometers

7. What is mean by isoseismal?In seismology an isoseismal map is used to show lines of equal felt seismic intensity, generally measured on the Modified Mercalli scale. Such maps help to identify earthquake epicenters, particularly where no instrumental records exist, such as for historical earthquakes.

8. What is a fault?A fracture in a rock formation along which there has been movement of the blocks of rock on either side of the plane of fracture. Faults are caused by plate-tectonic forces.In geology, a fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement along the fractures as a result of earth movement.

9. Mention the types of Earth Quake.Blind thrust earthquake.Doublet earthquake.Super Shear earthquake.Interplate earthquake.Megathrust earthquake.

10. Define magnitude.Magnitude is a measure of the amount of energy released during an earthquake. It may be expressed using several magnitude scales

UNIT-II : PART-A

1. Mention the types of vibrationFree vibrationForced vibration

2. Define static analysisStatic analysis, static projection, and static scoring are terms for simplified analysis wherein the effect of an immediate change to a system is calculated without respect to the longer term response of the system to that change. Such analysis typically produces poor correlation to empirical results.

3. Define dynamic analysis.Dynamic analysis or dynamic scoring, is an attempt to take into account how the system is likely to respond to the change.

4. Define free vibration.The vibration of a structure that occurs at its natural frequency, as opposed to a forced vibration

Free vibration is a vibration in which energy is neither added to nor removed from the vibrating system.

5. Define forced vibration

Forced vibration is when an alternating force or motion is applied to a mechanical system. Examples of this type of vibration include a shaking washing machine due to an imbalance, transportation vibration (caused by truck engine, springs, road, etc.), or the vibration of a building during an earthquake. In forced vibration the frequency of the vibration is the frequency of the force or motion applied, with order of magnitude being dependent on the actual mechanical system.

6. What are the methods to be followed to derive the equation of motion?Graphical methodEnergy Method.

7. What is meant by damping?

Damping is a phenomenon by which mechanical energy is dissipated (usually converted asthermal energy) in dynamic systems.

8. Draw the spring mass system and free body diagram for undamped free vibration

system.

9. Define vibration analysis.

A technique that uses instruments to monitor and analyze machine vibration to determine if the machine is working properly. Vibration analysis is of the most common techniques used.

10. Define accelerometers.

An accelerometer is a device that measures proper acceleration. The proper acceleration measured by an accelerometer is not necessarily the coordinate acceleration (rate of change of velocity).

UNIT-III -PART-A

1. Why is strong columns – weak beams configuration is preferred for making earthquake resistant buildings?Lack of stiffness or strength in the column will lead to formation of plastic hinge in them. Under such condition it is preferred to have a formation of moment hinge in the beams instead of column.

2. What is design spectrum?A design spectrum is simply a plot of the peak or steady-state response (displacement, velocity or acceleration) of a series of oscillators of varying natural frequency, that are forced into motion by the same base vibration or shock.

3. What are the common types of damages observed in RC buildings?The damage is mostly

due to failure of infill failure of columns or beams Spalling of concrete in columns. Cracking or buckling due to excessive bending combined with dead load may

damage the column

4. What is an irregular building?A regular structure has no significant discontinuities in plan, vertical configuration, or lateral force resisting systems. An irregular structure, on the other hand, has significant discontinuities.

5. What is floating column? How does their presence affect the seismic performance of a building?A column is supposed to be a vertical member starting from foundation level and transferring the load to the ground. The term floating column is also a vertical element which ends (due to architectural design/ site situation) at its lower level (termination Level) rests on a beam which is a horizontal member.

6. Define ductility.Ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Malleability, a similar property, is a material's ability to deform under compressive stress; this is often characterized by the material's ability to form a thin sheet by hammering or rolling.

7. Define seismic weight.The seismic weight is usually composed of the dead loads and a fraction of the live loads and the snow loads. The fractions of the live and snow loads depend on the type of the structure, they are defined in section 4.1.9 of the NBC-95 code. Note that the seismic weight does not include any of the static seismic basic loads.

8. Define shear wall.A shear wall is a wall composed of braced panels (also known as shear panels) to counter the effects of lateral load acting on a structure. Wind and seismic[1] loads are the most common loads braced wall lines are designed to counterac

9. Mention the different types of shear wallWood Framed Shear Walls, Metal Stud Framed Shear Walls, Masonry Shear Walls

UNIT-IV

1. What is the philosophy of seismic design of structures?

The earthquake design philosophy may be summarized as follows (Figure 1):

(a) Under minor but frequent shaking, the main members of the building that carry vertical and horizontal forces should not be damaged; however building parts that do not carry load may sustain repairable damage.

(b) Under moderate but occasional shaking, the main members may sustain repairable damage, while the other parts of the building may be damaged such that they may even have to be replaced after the earthquake; and

(c) Under strong but rare shaking, the main members may sustain severe (even irreparable) damage, but the building should not collapse.

2. What is a seismic code?

Seismic code is a reference produced by Indian standards to construct the seismicresistance structures with good performance and durability.IS 1893 (Part I), 2002,IS 4326, 1993,IS 13827, 1993,IS 13828, 1993,IS 13920, 1993,IS 13935, 1993,

3. What is the design base shear?

The equivalent static force procedure in the International Building Code (IBC 1617.4) specifies the following formula for calculating base shear (V):V = CsW

where the seismic response coefficient, Cs, is defined as: Cs = (2/3) FvS1IE / R T

4. What do you mean by Braced frames?A Braced Frame is a structural system which is designed primarily to resist wind and earthquake forces. Members in a braced frame are designed to work in tension and compression, similar to a truss. Braced frames are almost always composed of steel members.

5. What is cyclic loading and give some examples?

Some parts or portions of a part are exposed to fluctuating loads. Fatigue Analysis tells us how the material reacts to these loads with respect to Time. When a material is loaded too much, it may break even if the resultant stress is less than the Ultimate stess. For example if you twist a wire again and again with the same effort, it breaks after a point, though you're applying the same force. This explains cyclic loading

6. What is non cyclic loading and give some examples?

A load is non-cyclic when it varies between sectors and involves at least one harmonic index greater than zero. ANSYS supports linear static cyclic symmetry analyses with non-cyclic loading. Support is also available for a cyclic analysis having some combination of cyclic and non-cyclic loading.

UNIT –V PART-A

1. Mention the software packages for seismic analysis &design.

Seisware software, OMNI 3D, Oasys software

2. Mention the application of computer packages.

3. What is meant by seismic analysis.

Seismic Analysis is a subset of structural analysis and is the calculation of the response of a building (or nonbuilding) structure to earthquakes.

4.What is meant by preprocessing.

The translator processes each source file in a series of phases. Preprocessing constitutes the earliest phases, which produce a translation unit .Preprocessing treats a source file as a sequence of text lines.

5.Mention two software packages employ finite element method as a tool for the

analysis.

PERIODIC3 NEi Software Diana software

6. Define Logarithmic Decrement.

Logarithmic decrement, δ, is used to find the damping ratio of an underdamped system in the time domain. The logarithmic decrement is the natural log of the ratio of the amplitudes of any two successive peaks:

where x(t) is the amplitude at time t and x(t+nT) is the amplitude of the peak n periods away, where n is any integer number of successive, positive peaks. The damping ratio is then found from the logarithmic decrement:

The damping ratio can then be used to find the natural frequency ωn of vibration of the system from the damped natural frequency ωd:

where T, the period of the waveform, is the time between two successive amplitude peaks of the underdamped system.

7.Define Resonance.

Resonance is the tendency of a system to oscillate with greater amplitude at some frequencies than at others. Frequencies at which the response amplitude is a relative maximum are known as the system's resonant frequencies, or resonance frequencies

8.What are the effect of vibration.

9.Define Transmissibility Ratio.

Transmissibility is the ratio of output to input.

Transmissibility (T) = output/input

T>1 means amplification and maximum amplification occurs when forcing frequency (ff) and natural frequency (fn) of the system coincide.

There is no unit designation for transmissibility, although it may sometimes be referred to as the "Q" factor.

10.Define Natural Frequency.

The natural frequency is the rate at which an object vibrates when it is not disturbed by an outside force. Each degree of freedom of an object has its own natural frequency, expressed as ωn (omega subscript n). Frequency (omega) is equal to the speed of vibration divided by the wavelength

(lambda), . Other equations to calculate the natural frequency depend upon the vibration system. Natural frequency can be either undamped or damped, depending on whether the system has significant damping. The damped natural frequency is equal to the square root of the collective of one minus the damping ratio squared multiplied by the natural frequency,

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