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http://www.iaeme.com/IJCIET/index.asp 90 [email protected] International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 6, November-December 2016, pp. 90–105, Article ID: IJCIET_07_06_011 Available online at http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=7&IType=6 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 © IAEME Publication ENHANCED SEISMIC RESISTANCE OF STEEL BUILDINGS USING VISCOUS FLUID DAMPERS PouyaAzarsa M. Tech in Structural Engineering, Department of Civil Engineering, Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana, India Mahdi Hosseini Ph.D. Scholar Student in Structural Engineering, Department of Civil Engineering, Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana , India Seyed Amin Ahmadi Ph.D. Scholar Student in Computer Science and Engineering, Department of Computer Science and Engineering, Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana, India N.V. Ramana Rao Professor, Department of Civil Engineering, Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana, India ABSTRACT In recent years considerable attention has been paid to research and development of structural control devices with particular emphasis on diminish of wind and seismic response of buildings. In order to control the vibration response of building during seismic events, energy absorbing passive damping devices are most commonly used for energy absorption. The present work deals in reducing the seismic response using fluid viscous dampers connected to Steel Bracing for 12 floors when subjected to a seismic excitation of Bhuj 2001 earthquake ground motion. It is considered a regular steel structure with 3 variants of confirmation: Normal Steel Building, Steel Building with ‘X’ Bracing and Steel Building with Dampers. Nonlinear time history analysis has been performed for structures and observed the reduction in seismic response. Parameters studied are roof displacements, storey drifts and base shears. SAP2000 software analysis engine is used as the software tool for the seismic analysis of the structure. Roof displacements decreased highly to an extent of 50% and 38% compared to normal steel building and building with X bracings respectively. The result analysis shows a reduction of 55-60% in base shear and 35-9% in storey drift for structures equipped with fluid viscous when compared to normal steel building and building with X bracings respectively. It expresses that providing bracings with damper in outer frame of structure is more efficient than structure with only dampers. Key words: Nonlinear time history analysis, SAP2000, Bhuj ground motion data, Passive control systems, fluid viscous dampers.

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Page 1: ENHANCED SEISMIC RESISTANCE OF STEEL BUILDINGS USING … · 2016-11-16 · working on building structures. The following list represents advance and enhanced features of SAP2000 V

http://www.iaeme.com/IJCIET/index.asp 90 [email protected]

International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 6, November-December 2016, pp. 90–105, Article ID: IJCIET_07_06_011

Available online at http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=7&IType=6

ISSN Print: 0976-6308 and ISSN Online: 0976-6316

© IAEME Publication

ENHANCED SEISMIC RESISTANCE OF STEEL

BUILDINGS USING VISCOUS FLUID DAMPERS

PouyaAzarsa

M. Tech in Structural Engineering, Department of Civil Engineering,

Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana, India

Mahdi Hosseini

Ph.D. Scholar Student in Structural Engineering, Department of Civil Engineering,

Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana , India

Seyed Amin Ahmadi

Ph.D. Scholar Student in Computer Science and Engineering,

Department of Computer Science and Engineering, Jawaharlal Nehru Technological University Hyderabad

(JNTUH), Hyderabad, Telengana, India

N.V. Ramana Rao

Professor, Department of Civil Engineering,

Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad, Telengana, India

ABSTRACT

In recent years considerable attention has been paid to research and development of structural

control devices with particular emphasis on diminish of wind and seismic response of buildings. In

order to control the vibration response of building during seismic events, energy absorbing passive

damping devices are most commonly used for energy absorption. The present work deals in

reducing the seismic response using fluid viscous dampers connected to Steel Bracing for 12 floors

when subjected to a seismic excitation of Bhuj 2001 earthquake ground motion. It is considered a

regular steel structure with 3 variants of confirmation: Normal Steel Building, Steel Building with

‘X’ Bracing and Steel Building with Dampers. Nonlinear time history analysis has been performed

for structures and observed the reduction in seismic response. Parameters studied are roof

displacements, storey drifts and base shears. SAP2000 software analysis engine is used as the

software tool for the seismic analysis of the structure. Roof displacements decreased highly to an

extent of 50% and 38% compared to normal steel building and building with X bracings

respectively. The result analysis shows a reduction of 55-60% in base shear and 35-9% in storey

drift for structures equipped with fluid viscous when compared to normal steel building and

building with X bracings respectively. It expresses that providing bracings with damper in outer

frame of structure is more efficient than structure with only dampers.

Key words: Nonlinear time history analysis, SAP2000, Bhuj ground motion data, Passive control

systems, fluid viscous dampers.

Page 2: ENHANCED SEISMIC RESISTANCE OF STEEL BUILDINGS USING … · 2016-11-16 · working on building structures. The following list represents advance and enhanced features of SAP2000 V

Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 91 [email protected]

Cite this Article: Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana

Rao, Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers. International

Journal of Civil Engineering and Technology, 7(6), 2016, pp.90 – 105.

http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=7&IType=6

1. INTRODUCTION

1.1. Need for Present Study

All structures are subjected to vibration. Recent destructive earthquakes in Bhuj have shown how

vulnerable our structures and societies remain to natural phenomena. The enormous losses inflicted by

such earthquake have motivated ever more stringent requirements on the performance of structural

systems, in reducing of seismic effect on structure. The cost and performance requirements for both

buildings and equipment have motivated advances in the field of Structural Control, which deals with

methodologies for the protection of high performance structural systems. The Fluid viscous Damper is a

device that is designed to effectively isolate such structures from harmful vibrations.

Use of fluid viscous dampers to dissipate the earthquake energy so they reduces roof displacements,

story drifts and base shear.

1.2. Aims and Objectives of the Study

To Study the seismic behavior of structures with 12 floor levels buildings with and without bracings using

non linear time history analysis. To illustrate the effects of Fluid Viscous dampers with varying floor levels

by using non linear time history analysis.

1.3. Scope of Work

Application of Fluid viscous dampers in the structure using SAP2000 for twelve story structures and

discussing the varying effects as to reduce the base shear, storey drifts and roof displacements in structural

compared to buildings with and without bracings and economically safe way.

1.4. Passive control system

The most mechanically simple set of control schemes is enclosed in the passive control category, which

has been widely accepted for civil engineering application. Housner et al. have both provided brief

overviews on structural control, including proper definitions for the various types of control practically

implemented in structures. According to them a passive control system is one that does not require an

external power source. All forces imposed by passive control devices develop as direct responses to the

motion of the structure. Hence, sum of the energy of both the device and the primary system will be

constant.The main purpose of these systems is to efficiently dissipate vibrational energy, and the various

methods of achieving this can be categorized in two ways. The first method includes converting kinetic

energy directly to heat, such as through the yielding of metals, the deformation of visco-elastic solids and

fluids, or the implementation of friction sliders. The second method works on transferring energy among

two or more of the vibrational modes of the building, generally achieved by adding a supplemental

oscillator that absorbs the vibrations of the primary structures. Tune mass damper, tune liquid damper, base

isolation are example of passive system.

1.5. Dampers

Damping is one of many different methods that have been proposed for allowing a structure to achieve

optimal performance when it is subjected to seismic, wind storm, blast or other types of transient shock

and vibration disturbances. Dampers can be installed in the structural frame of a building to absorb some of

the energy going into the building from the shaking ground during an earthquake. The dampers reduce the

energy available for shaking the building. This means that the building deforms less, so the chance of

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 92 [email protected]

damage is reduced.The concept of supplemental dampers added to a structure assumes that major of the

input energy to the structure will be absorbed not by the structure itself, but rather by supplemental

damping elements. Device that have most commonly been used for seismic protection of structures include

viscous fluid dampers, visco-elastic solid dampers, friction dampers, and metallic dampers.

1.6. Viscous Fluid Dampers

Fluid viscous dampers were initially used in the military and aerospace industry. They were adapted for

use in structural engineering in the late 1980’s and early 1990’s (Makris and Constantinou, 1990,

Constantinou and Symans, 1992). Fluid viscous dampers typically consist of a piston head with orifices

contained in a cylinder filled with a highly viscous fluid, usually a compound of silicone or a similar type

of oil. Energy is dissipated in the damper by fluid orificing when the piston head moves through the fluid

(Hanson and Soong, 2001).The fluid in the cylinder is nearly incompressible, and when the damper is

subjected to a compressive force, the fluid volume inside the cylinder is decreased as a result of the piston

rod area movement. A decrease in volume results in a restoring force. This force is undesirable and is

usually prevented by using a run-through rod that enters the damper, is connected to the piston head, and

then passes out the other end of the damper. Another method for preventing the restoring force is to use an

accumulator (Symans and Constantinou, 1998). An accumulator works by collecting the volume of fluid

that is displaced by the piston rod and storing it in the make-up area. As the rod retreats, a vacuum that has

been created will draw the fluid out. A damper with an accumulator is illustrated in .Experimental and

analytical studies of buildings and bridges with fluid dampers is done & manufactured by Taylor devices

Inc. The Taylor's device which has been filled with silicone oil consists of a stainless steel piston with a

bronze orifice head and an accumulator.

1.7. About SAP 2000

SAP2000 offers the widest assortment of analysis and design tools available for the structural engineer

working on building structures. The following list represents advance and enhanced features of SAP2000

V 16:

• User interface

• Default templates for quick Starting

• Grid System

• Structural components such as joints, frames, cables, tendons, shell, solids, links, hinges, spring, etc.

• Automatic code based loadings.

• Design of Steel, Concrete, Aluminium and cold formed frames.

• Quick & advance reporting.

2. METHODOLOGY

2.1. Time History Analysis

Time history analysis is a step by step procedure of the dynamic response of the structure to a specified

loading that may vary with time. The analysis may be linear or non linear. Time history analysis is used to

determine the dynamic response to a structure subjected to arbitrary loading. The dynamic equilibrium

equations to be solved are given by

��� + ��� +�� = �()

Where M is the diagonal mass matrix, C is the damping matrix and K is the stiffness matrix and r(t) is

the applied load,�,�� ,�� are the displacements, velocities and accelerations of the structure. If the load

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 93 [email protected]

includes ground accelerations, the displacements, velocities and accelerations are relative to this ground

motion.

There are several options that determine the type of time history case to be performed:

• Linear vs. Non linear.

• Modal vs. Direct-integration

• Transient vs. periodic

2.3. Upload Accelerograms to SAP 2000

Define the accelerogram in SAP2000 - The accelerogram must be uploaded to SAP2000 as FUNCTION

FROM FILE an option which can be selected from the drop-down list

Define the accelerogram in SAP2000. We can select:

• Name of the function (e.g. Bhuj earthquake)

• Location of the file by using the button BROWSE.

• Number of lines to skip (0 for Bhuj database)

• Number of points per line (0 for Bhuj database)

2.4. Step By Step Process To Perform The Non-Linear Modal Time History Analysis

• Define the ground acceleration u�� numerically at every time step

• Define the structural properties.

a. Determine the mass matrix m and lateral stiffness matrix k

b. Estimate the modal dumping ratios ζ�

Determine the natural frequencies ω� and natural modes of vibration

• Determine the modal components s�of the effective earthquake force distribution.

• Compute the response contribution of the nth mode by the following steps, which are repeated for all modes.

• Perform static analysis of the building subjected to lateral forces ��to determine r���, the modal static

response for each desired response quantity r.

• Determine the pseudo –acceleration response A�(t)of the nth mode SDOF system using numerical step

methods.

• Determine ��(t) using summation rule given in equation to get the final response.

3. NUMERICAL ANALYSIS

The aim of the present work is to reduce seismic response of structures using passive vibration control

system namely Fluid viscous dampers in SAP2000. The buildings with 12 floor level are considered for

the study and the structures are subjected to seismic excitations on steel Building with& without bracing

and dampers. The Bhuj 2001earthquake data is used as ground motion data for performing nonlinear time

history analysis. The dampers are installed in the structures only in the exterior frames.

3.1. Structural Specifications

Details of 12 storied symmetric building:

Geometry:

Foundation Depth = 1.5m

Each storey height = 3 m

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 94 [email protected]

Plan dimensions = 4.5 mx4.5 m for each bay

No. of Bays = 6

No. of spans = 4 Table 1 Structural specifications of buildings.

The following figures show the plan of the building, rendered three dimensional view of the building

and the elevation view with dampers installed in the building.

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 95 [email protected]

3.2. Loading

Gravity loading: Dead load of the structure will automatically calculated by the software itself based on

the sizes and properties assigned. The slab is assumed to be of 125mm thick and exterior walls are of

230mm thick and interior walls are of 115mm thick The live load of 3kN/m2 is considered for entire floor

and floor finishes of 1.5kN/m2 is applied as super imposed dead load.

3.3. Non-Linear Model Time History Analysis in SAP 2000

Following are the general sequence of steps involved in performing NLTHA usingSAP2000 in the present

study: Figure 4.1 shows acceleration time history of Bhuj Earthquake of January 26, 2001 at 08:46:42.9

I.S.T Mag: 7.0 mb, 7.6 Ms

Lat& Long: 23 02 N, 72 38 E

Comp: N 12 W

Accelerogram Band pass filtered between 0.07 Hz and 27.0 Hz

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

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Initial Velocity= -.1181E-02 m/s

Initial Displacement = -1.006 mm

Peak Acceleration = -0.78236m/s/s at 34.945 sec.

26706 Acceleration data points (in m/s/s) at .005 sec

The time history loading is applied from earthquake data functions. Bhuj is a place located in the state

of Gujarat which is a high intensity earthquake zone of zone factor 0.36 which comes under the Zone-V

according to the classification of seismic zones by IS 1893-2002 part-1.The records are defined for the

acceleration points with respect to a time-interval of 0.005 second. The acceleration record has units of

m/���� and has a total number of 26,706 acceleration data

Figure 6 Acceleration Vs Time graph for a Bhuj ground motion data

3.4. Damper Modeling

The Fluid viscous dampers in the system are defined as link/support property applied to the link used. The

parameters selected to define utilized dampers in the SAP2000 program are as follows. Non Linear Link

Type: DAMPER, damper coefficient is calculated as per Taylor devices [1] F=CVα. Damper coefficient in

U1 U2 with 350kN.s/m for both linear and nonlinear, and stiffness of 2000Kn/cm [1]. The linear properties

of stiffness is set to be zero, as viscous damper are velocity dependent and do not resist static loads. The

damper properties has draw to the structure using DRAW 2 JOINT LINK and assigning property DAMP1

to selected bracings in SAP2000.

3.5. Analysis Case

Nonlinear Time History case by using the BHUJ function applied in gravity direction by defining the

number of output steps are 26,706 and minimum step size is 0.005sec.

4. RESULTS AND DISCUSSIONS

Nonlinear time history analysis is performed in SAP2000 for12 floor levels with and without damper using

Bhuj 2001 ground motion data. The buildings were observed how damper is effective in reducing seismic

response.12 storied structures are analyzed with and without fluid viscous damper. The dampers are placed

only in the exterior frames of the structure. The parameters studied are roof displacements, storey drifts

and base shears and the results are presented as follows.

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 97 [email protected]

4.1. Roof Displacements

Figure 7 Roof displacement Vs Time for a 12 storied structure in X direction

Figure 8 Roof displacement Vs Time for a 12 storied structure in Y direction

The maximum and minimum roof displacement for a 12 storied structure are 502.1mm, -517.3mm and

557.5mm, -419.3mm in X and Y directions respectively.

Figure 9 Roof displacement Vs Time for a 12 storied structure in X direction with ‘X’ bracings

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 98 [email protected]

Figure 10 Roof displacement Vs Time for a 12 storied structure in Y direction with ‘X’ bracings

The maximum and minimum of roof displacement for a 12 storied structure with X bracings are

336.3mm, -377.3mm and 355.2mm, 340.8mm in X and Y directions respectively.

Figure 11 Roof displacement Vs Time for a 12 storied structure in X direction with Dampers

Figure 12 Roof displacement Vs Time for a 12 storied structure in Y direction with dampers

The maximum and minimum of roof displacement for a 12 storied structure are 264.7mm, 252.0mm

and 225.1mm, 208.4mm in X and Y directions respectively.

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 99 [email protected]

4.2. Base shears

Figure 13 Base shear Vs Time for a 12 storied structure in X direction

The maximum and minimum base shears of a 12 storied structure are 6672 kN and 6387kN @

43.38sec and 44.65 seconds in X directions respectively.

Figure 14 Base shear Vs Time for a 12 storied structure in Y direction

The maximum and minimum base shears of a 12 storied structure are 5468kN and 5276kN @ 50.13sec

and 48.84 seconds in Y directions respectively.

Figure 15 Base shear Vs Time for a 12 storied structure in X direction with ‘X’ bracings

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 100 [email protected]

The maximum and minimum base shears of a 12 storied structure are 9877kN and 8588kN @ 47.37sec

and 47.91 seconds in X directions respectively.

Figure 16 Base shear Vs Time for a 12 storied structure in Y direction with ‘X’ bracings

The maximum and minimum base shears of a 12 storied structure are 9767kN and 9801kN @ 46.7sec

and 47.14 seconds in Y directions respectively.

Figure 17 Base shear Vs Time for a 12 storied structure in Y direction with Dampers

The maximum and minimum base shears of a 12 storied structure are 2985 kN and 2269 kN @

40.23sec and 47.86 seconds in X directions respectively.

Figure 18 Base shear Vs Time for a 12 storied structure in Y direction with dampers

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 101 [email protected]

The maximum and minimum base shears of a 12 storied structure are 4776 kN and 4392kN @

42.41sec and 43.02 seconds in Y directions respectively.

Figure 19 Roof displacement for 12 storied structures in X direction

Figure 20 Roof displacement for 12 storied structures in Y direction

5. DISCUSSIONS

According to results obtained, the discussions are presented as follows

5.1. Performance on normal steel structures (without bracing and without dampers) under

nonlinear time history analysis.

a) Roof displacements

• The maximum and minimum roof displacements for a 12 storied structure are 502.1mm, -517.3mm and

557.5mm, -419.3mm in X and Y directions respectively.

It has been observed that as the number of floors is increasing, the roof displacements also increased

and the maximum roof displacement had occurred in 12 storied structures in Y direction.

502.1 517.3

336.3377.3

264.7 252

12 storeys +ve 12 storeys -ve

roof Disp. of steel builbing by time history displacement in X-direction

roof Disp of building with 'X' bracings x-direction

roof Disp of building with dampers x-direction

557.5

419.3

355.2 340.8

255.1208.4

12 storeys +ve 12 storeys -ve

roof Disp of steel builbing by time history displacement in y-direction

roof Disp of building with 'X' bracings y-direction

roof Disp of building with dampers y-direction

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 102 [email protected]

b) Storey Drifts

• The maximum storey drift for a 12 storied structure in X & Y direction is 17.6mm, 19.2 mm respectively.

c) Base Shears

• The maximum and minimum base shears of a 12 storied structure are 6672 kN and 6387KN @ 43.38sec and

44.65 seconds in X directions respectively.

• The maximum and minimum base shears of a 12 storied structure are 5468kN and 5276kN @ 50.13sec and

48.84 seconds in Y directions respectively.

It has been observed that as the number of floors increases, the base shear also increased and the

maximum base shear had occurred in 12 storied building.

5.2. Performance of structures with ‘X’ bracings provided at outer frame of the building

a) Roof Displacements

• The maximum and minimum of roof displacements for a 12 storied structure are 336.3mm, -377.3mm and

355.2mm, 340.8mm in X and Y directions respectively.

When the buildings are equipped with Bracing in Outer Frame of Structures, drastic reduction has

taken place in roof displacements. The roof displacements decreased up to 33% respectively for 12 storied

buildings respectively.

b) Storey Drifts

• The maximum storey drift for a 12 storied structure in X & Y direction is 12.4mm, 13.1 mm respectively.

The buildings equipped with X bracings have shown a drastic reduction in storey drifts and the

percentage reduction in storey drifts are found to be 31% respectively for 12 storied buildings respectively.

c) Base Shears

• The maximum and minimum base shears of a 12 storied structure are 9877kN and 8588kN @ 47.37sec and

47.91 seconds in X directions respectively.

• The maximum and minimum base shears of a 12 storied structure are 9767kN and 9801kN @ 46.7sec and

47.14 seconds in Y directions respectively

When the buildings are equipped with ‘X’ Bracings in Outer Frame of Structure, the base shears

increased by 32% in 12 storied buildings respectively.

5.3. Performance of structures with fluid viscous

a) Roof displacements

• The maximum and minimum of roof displacements for a 12 storied structure are 264.7mm,

252.0mm and 225.1mm, 208.4mm in X and Y directions respectively.

When the buildings are equipped with Fluid viscous damper in Outer Frame of Structures, drastic

reduction has taken place in roof displacements. the roof displacements variation of 12 storied decreased

up to 50%when compare to normal steel building and 38% when compare to buildings with X bracings

respectively.

b) Storey Drifts

• The maximum storey drift for a 12 storied structure in X & Y direction is 11.4mm, 11.7 mm respectively.

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Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 103 [email protected]

The buildings equipped with damper have shown a drastic reduction in storey drifts when compared to

steel building with and without bracings. The storey drifts variation of 12 storied decreased up to

35%when compare to normal steel building and 9% when compare to buildings with X bracings

respectively.

c) Base Shears

• The maximum and minimum base shears of a 12 storied structure are 2985 kN and 2269 kN @ 40.23sec and

47.86 seconds in X directions respectively.

• The maximum and minimum base shears of a 12 storied structure are 4776 kN and 4392kN @ 42.41sec and

43.02 seconds in Y directions respectively

When the buildings are equipped with Fluid viscous damper in Outer Frame of Structures, drastic

reduction has taken place in base shears. the base shears variation of 12 storied decreased up to 55% when

compare to normal steel building and 60% when compare to buildings with X bracings respectively.

6. CONCLUSIONS

• The Fluid viscous damper were found to be excellent seismic control devices for controlling forced

Responses such as base shear, roof displacements and storey drift for buildings with varying stories

o The base shears decreased up to 55% when compare to normal steel building and 60% when

compare to buildings with X bracings.

o The roof displacements decreased up to 50% when compare to normal steel building and 38%

when compare to buildings with X bracings.

o The storey drifts decreased up to 35% when compare to normal steel building and 9% when

compare to buildings with X bracings.

• Reduction in Base shear did not follow any trend with increase in number of floors when buildings are

equipped with Fluid viscous damper,

• For the damper building, the reduction in storey drift decreases with increase in number of floors.

• Buildings with ‘X’ bracings reduce roof displacement and storey drift, but there is much increase in base

shear.

It can also conclude that providing bracings with damper in outer frame of structure is more efficient

than structure with only dampers.

7. SCOPE FOR FURTHER WORK

The further studies can be done by changing the position of placement of dampers in the core of the

building on asymmetry in elevation and plan. It can also be extent by replacing the shear wall with

dampers in structure.

REFERENCE

[1] Flavia S. Florea, "Behaviour of Seismic Resistant Eccentrically Braced Frames", Technical University

of Civil Engineering, Bucharest, Romania, February 15, 2010.

[2] FloreaFlavia- Simona and RosuLoredana Elena, "Enhanced Seismic Resistance of Steel Structures using

Passive Energy Dissipation Devices", Technical University of Civil Engineering.

[3] G.S. Balakrishna and Jini Jacob, "Seismic Analysis of Building using Two Types of Passive Energy

Dissipation Devices”, IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE), e-ISSN: 2278-

1684, p-ISSN: 2320-334X, PP 13-19.

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Enhanced Seismic Resistance of Steel Buildings Using Viscous Fluid Dampers

http://www.iaeme.com/IJCIET/index.asp 104 [email protected]

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International Journal of Research in Engineering and Technology (IMPACT: IJRET), Vol.2, Issue 9,

Sep 2014.

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Frame Structures Equipped With Viscous Dampers” Italy

[6] M.C. Constantinou, M.D. Symans “seismic response of structures With supplemental damping, State

University of New York Department of Civil Engineering Buffalo, NY 14260

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buildings under seismic Loading” Fourth Asia-Pacific Conference on FRP in Structures (APFIS 2013)

[8] V. SadeghiBalkanlou, M. Reza BagerzadehKarimi, B. BagheriAzar and AlaeddinBehravesh “

Evaluating Effects of Viscous Dampers on optimizing Seismic Behavior of Structures”, Young

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Various Regression Level for Fluid Dampers. International Journal of Civil Engineering and

Technology (IJCIET), 7(5), 2016, pp.111–123

[15] S.P.Pawar, Dr.C.P.Pise, Y.P.Pawar, S.S.Kadam, D. D. Mohite, C. M. Deshmukh and N. K. Shelar,

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Page 16: ENHANCED SEISMIC RESISTANCE OF STEEL BUILDINGS USING … · 2016-11-16 · working on building structures. The following list represents advance and enhanced features of SAP2000 V

Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp

AUTHOR’S PROFILE

Pouya Azarsa

Jawaharlal Nehru Technological Universit

Telengana, India

Mahdi Hosseini

Engineering, Jawaharlal Nehru Technological University Hyderabad (JNTUH),

Hyderabad, Telengana , India

Dynamics ,Structural Optimization

,Earthquake Engineering

Seyed Amin Ahmadi

Engineering, Dept. of

Technological University Hyderabad (JNTUH), Hyderabad, Telengana , India,

interest: Network and Network Security, IT, Network M

Professor. N.V.

Technological Universit

Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

http://www.iaeme.com/IJCIET/index.asp 105

Azarsa, M.Tech in Structural Engineering, Dept. of

Jawaharlal Nehru Technological University Hyderabad (JNTUH), Hyderabad

, India

Mahdi Hosseini, Ph.D. scholar student in Structural Engineering, Dept. of

Jawaharlal Nehru Technological University Hyderabad (JNTUH),

Hyderabad, Telengana , India ,Research interest: Structural Engineering

,Structural Optimization, structural design, Reinforced Concrete Structures

,Earthquake Engineering.

Seyed Amin Ahmadi Olounabadi Ph.D. scholar student in

Dept. of Computer Science and Engineering,

Technological University Hyderabad (JNTUH), Hyderabad, Telengana , India,

Network and Network Security, IT, Network Management

N.V. Ramana Rao, Dept. of Civil Engineering,

Technological University Hyderabad (JNTUH), Hyderabad,

Pouya Azarsa, Mahdi Hosseini, Seyed Amin Ahmadi and Prof. N.V. Ramana Rao

[email protected]

ech in Structural Engineering, Dept. of Civil Engineering,

y Hyderabad (JNTUH), Hyderabad,

Structural Engineering, Dept. of Civil

Jawaharlal Nehru Technological University Hyderabad (JNTUH),

,Research interest: Structural Engineering ,Structural

Reinforced Concrete Structures,

Ph.D. scholar student in Computer Science and

Computer Science and Engineering, Jawaharlal Nehru

Technological University Hyderabad (JNTUH), Hyderabad, Telengana , India, Research

anagement

Civil Engineering, Jawaharlal Nehru

, Telengana, India