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International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
398 Urvesh Chhastiya, Dr. V. R. Panchal
Seismic Response of Segmental Building with Triple Friction
Pendulum Bearing
Urvesh Chhastiya
Postgraduate Student
M. S. Patel Department of Civil Engineering
CSPIT, CHARUSAT, Changa, India
Dr. V. R. Panchal
Professor and Head of Department
M. S. Patel Department of Civil Engineering
CSPIT, CHARUSAT, Changa, India
ABSTRACT
Base isolation is the one of the most accepted seismic protection system used in building. In present study, Friction
Pendulum Bearing and Triple Friction Pendulum Bearing are provided in base isolated building and segmental building.
The segmental building is a base isolated building whose superstructure is divided into several segments. Non linear time
history analysis is carried out for base isolated building and segmental building under near fault earthquake ground
motions. SAP 2000 is software used for this analysis. At the end of analysis, different parameter are compared.
Keywords
Seismic isolation, segmental building, Friction Pendulum Bearing, Triple Friction Pendulum Bearing, non linear
time history
1. INTRODUCTION
The earthquake occurs due to sudden release of some stored energies in the earth’s crust and upper mantle.
Due to ground motion, there is large amount of damage caused to the structure. From last few years, the
earthquake resistance design of structure has been based on a ductility design concept. This traditional
method, strengthening the stiffness, strength and ductility of the structure has been common use for long time.
Therefore, the dimension of the structural member and the consumption of material are expected to increase,
which increases the cost of building as well as larger seismic responses due to larger stiffness of the structure.
To overcome this disadvantage, base isolation is the best option. Seismic isolation is a technique that reduces
the effects of a earthquake by isolating the structure from earthquake. The basic idea behind the isolated
structure is to increase the time period of vibration of a structure. In this study, Friction Pendulum Bearing
(FPB) and Triple Friction Pendulum Bearing (TFPB) are used. The Friction pendulum bearing is a sliding
type isolation bearing and consists of a spherical stainless steel surface and an articulated slider, covered by
Teflon based composite material. The Triple Friction Pendulum Bearing (TFPB) differs from the single
Friction Pendulum Bearing (FPB) in that there are 3 friction pendulum mechanisms existing in each bearing
instead of just 1 mechanism. The segmental building is advanced concept compared to conventional base
isolation system, which distribute flexibility in superstructure. Figure 1 indicates the model of segmental
building, base isolated building and fixed base building. This Figure is taken from Reference [1].
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
399 Urvesh Chhastiya, Dr. V. R. Panchal
Figure 1.(a)segmental building(b)base isolated building(c)fixed base building
2. LITERATURE SURVEY
Desai & Gajjar (2012) carried out research on the structural control system for mid rise building. In this
paper, Segmental building analysed under 1940 EL centro and 1989 Loma prieta ground motions. The result
compare with fixed base building and base isolated building. Sable & Khose (2012) carried out work on
comparison of different bearing types performance in multistoried Building. The paper deals with the
comparison of different types of bearing and their performance. Authors concluded that base isolated building
give good performance compare to fixed base building.Fakhari & Amiri (2012) carried out work on nonlinear
response history analysis of TFPB installed between stories. Authors investigated application of TFPB in six
stories steel frame structure, while TFPB is installed at different levels; such as base, first story, third story or
combination of them, and each state was compared with fixed-base and base isolated structure. The results
indicated that base and first story isolation systems are extremely effective in reduction of maximum drift
ratio and story shear force. Santhosh (2013) carried out work on seismic analysis of low to medium rise
building for base isolation. A six storey structure under both fixed base and seismically isolated boundary
conditions was studied to demonstrate the effectiveness of seismic isolation. Shaikh & Murnal (2015) carried
out research on base isolation at different levels in building. In this paper, seismic response of multistory
building supported on base isolation at different levels was investigated under earthquake time history
motions. A ten story building was modelled by using SAP2000. Time history analysis was conducted for the
1994 Northridge and 1940 El-Centro earthquakes. Authors concluded that segmental building gives
minimum base shear. Patare & Mehetre (2015) carried out work on earthquake analysis of top storey isolated
building using rubber isolator. In this paper, comparison done between fixed base building and top isolated
building. Authors concluded that top story isolated model show reduction the parameter. Bayoumi (2015)
carried out work on modelling of TFPB in SAP2000. G+10 storey building was modelled in SAP2000. In this
paper, non linear time history analysis carried out. Author described how to enter input parameters of TFPB.
3. PROBLEM FORMULATION
The (G+9) storey RCC building considered for analysis. Building has plan dimension of 25m ×15m and each
bay is 5m in X direction and 5m in Y direction as shown in Figure 2. The XZ view of segmental building, base
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
400 Urvesh Chhastiya, Dr. V. R. Panchal
isolated building and fixed base building shown in Figure 3. In segmental building, FPB and TFPB are
provided between 2 & 3 and 6 & 7 storey. The structural details for the building are shown in Table
1.Nonlinear time history analysis is carried out in SAP2000 software under near-fault earthquake ground
motions. The earthquake ground motions used in the study are indicated in Table 2. FPB and TFPB are used
as base isolation and their link properties are indicated in Tables 3 and 4, respectively.
(a) (b) (c)
Figure 3. (a) XZ view of segmental building (b) XZ view of base isolated building (c) XZ view Of fixed base building
Figure 2. Plan of the building
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
401 Urvesh Chhastiya, Dr. V. R. Panchal
Table 1. Structural details of the building
Sr.No. Storey (G+9) Data
1 Plan Dimension 25 m × 15 m
2 Height of Storey 3.1 m
3 Size of Beams 0.4 m × 0.7 m
4 Size of Columns 0.5 m×0.5 m
5 Thickness of Slab 0.120 m
6 Live Load on Floor 2.5 kN/m2
7 Grade of Concrete M 20
8 Grade of Steel Fe 415
9 Density of Concrete 25 kN/m3
Table 2. Details of Earthquake ground motions Near-fault earthquake
ground motions
(Normal Component)
Recording
station
Duration (sec) PGD (m) PGV (m/sec) PGA (g)
October 15, 1979
Imperial Valley,
California
El Centro
Array #5
39.42 0.765 0.98 0.37
October 15, 1979
Imperial Valley,
California
El Centro
Array #7
36.9 0.491 1.13 0.46
January 17, 1994
Northridge, California
Newhall 60 0.381 1.19 0.72
June 28, 1992 Landers,
California
Lucerne
Valley
49.284 2.3 1.36 0.71
Table 3. Link property of friction pendulum bearing
Parameters
FPB
Base isolated building and segmental
building
Effective stiffness (kN/m) 545.97
Elastic Stiffness (kN/m) 300000
Friction Coefficient, Slow 0.093
Friction Coefficient, Fast 0.093
Rate Parameter (s/m) 1
Net Pendulum Radius (m) 5.49
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
402 Urvesh Chhastiya, Dr. V. R. Panchal
Table 4. Link property of triple friction pendulum bearing
Parameters
TFPB
Outer slider Inner slider
Effective stiffness (kN/m) 585.95 585.95
Effective damping 0.2567 0.2567
Elastic stiffness (kN/m) 5140.693 4383.117
Friction coefficient, Slow 0.095 0.081
Friction Coefficient, Fast 0.19 0.162
Rate Parameter 0.5 0.5
Net Pendulum Radius (m) 2.133 0.33
Stop Distance (m) 0.68 0.0092
4. ANALYSIS AND RESULT DISCUSSION
The seismic response of base isolated building and segmental building with FPB is compared with TFPB for
various Earthquake records. The time period of FPB and TFPB are taken same for various parameters. After
conducting the time history analysis, following result were obtained.
4.1 Time period
Figure 4 shows minimum time period in case of fixed base building and it increases in base isolated building
and segmental building.
Figure 4. Time period of fixed base building, base isolated and segmental building for FPB & TFPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
403 Urvesh Chhastiya, Dr. V. R. Panchal
4.2 Base shear
From the Figure 5, it is observed that base shear decreases in base isolated building with TFPB as compared to
base isolated building with FPB. Figure 6 shows that segmental building with TFPB give less base shear as
compared to segmental building with FPB.
Figure 5. Base shear of base isolated building with FPB and TFPB
Figure 6. Base shear of segmental building with FPB and TFPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
404 Urvesh Chhastiya, Dr. V. R. Panchal
4.3 Base displacement
From the Figure 7, it is observed that base displacement increases in TFPB isolated building as compared to
FPB isolated building. Figure 8 shows the base displacement of segmental building with FPB and segmental
building with TFPB. It indicates that base displacement increases in segmental building with TFPB as
compared segmental building with FPB.
Figure 7. Base displacement of base isolated building with FPB and TFPB
Figure 8. Base displacement of segmental building with FPB and TFPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
405 Urvesh Chhastiya, Dr. V. R. Panchal
4.4 Hysteresis behavior
Figures 9 to 12 show the hysteresis behavior of base isolated building with FPB and Figures 13 to 16 indicate
the hysteresis behaviour of base isolated building with TFPB under different earthquake ground
motions.Figures 17 to 20 show the hysteresis behavior of segmental building with FPB and Figures 21 to 24
indicate the hysteresis behaviour of segmental building with TFPB.
Figure 9. Hysteresis behavior of base isolated Figure 10. Hysteresis behavior of base isolated
building with FPB building with FPB
Figure 11.Hysteresis behavior of base isolated Figure 12.Hysteresis behavior of base isolated
building with FPB building with FPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
406 Urvesh Chhastiya, Dr. V. R. Panchal
Figure 13.Hysteresis behavior of base isolated Figure 14.Hysteresis behavior of base isolated
building with TFPB building with TFPB
Figure 15.Hysteresis behavior of base isolated Figure 16.Hysteresis behavior of base isolated
building with TFPB building with TFPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
407 Urvesh Chhastiya, Dr. V. R. Panchal
Figure 17. Hysteresis behavior of segmental Figure 18. Hysteresis behavior of segmental
building with FPB building with FPB
Figure 19. Hysteresis behavior of segmental Figure 20. Hysteresis behavior of segmental
building with FPB building with FPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
408 Urvesh Chhastiya, Dr. V. R. Panchal
Figure 21. Hysteresis behavior of segmental Figure 22.Hysteresis behavior of segmental
building with TFPB building with TFPB
Figure 23. Hysteresis behavior of segmental Figure 24. Hysteresis behavior of segmental
building with TFPB building with TFPB
International Journal of Engineering Technology, Management and Applied Sciences
www.ijetmas.com April 2017, Volume 5, Issue 4, ISSN 2349-4476
409 Urvesh Chhastiya, Dr. V. R. Panchal
5. CONCLUSIONS
The results of the research show that the time period of the base isolated building and segmental building
is increased by 71% and 77% respectively as compared to fixed base building.
The base shear is decreased in TFPB isolated building by 17% to 24% under various near fault ground
motions as compared to FPB isolated building for same time period.
For same study when the segmental building is considered, base shear is decreased in TFPB building by
38% to 53% under various near fault ground motions as compared to FPB building for same time period.
The base displacement is increased in base isolated TFPB building by 43% to 63% under near fault
ground motions as compared to base isolated FPB building.
In segmental building with TFPB, the base displacement is increased by 29% to 70% under near fault
ground motions as compared to segmental building with FPB.
REFERENCES 1) A. Desai, R. K. Gajjar, “Structural control system for mid rise building’, International Journal of Advanced
Engineering Technology”, Vol 3, pp. 30-33, April 2012.
2) K. Sable, J Khose, “Comparison of different bearing types performance in multistoried building”, International
Journal of Engineering and Innovative Technology, Vol 1, pp. 336-341, April 2012.
3) H. Fakhri, G. Amiri , “Nonlinear response history analysis of triple friction pendulum bearing installed between
stories”, Word Conference on Earthquake Engineering, Vol 2, pp 1-5, May 2012.
4) H. Santosh, “seismic analysis of low to medium rise building for base isolation”, International journal of research in
Engineering and Technology. Vol 3, pp 1-5,April 2013.
5) S. Shaikh, P. Murnal, “Base Isolation at different Levels in Building”, Journal of Civil Engineering and
Environmental Technology, Vol 2, pp 54-58, April 2015.
6) P. Patare, P. Mehetre, “Earthquake Analysis of Top Storey Isolated Building using Rubber Isolator”, International
Journal of Multidisciplinary and Current Research, Vol 3, pp. 555-557, June 2015.
7) P. Bayoumi, “Modelling of Triple Friction Pendulum Bearing in SAP2000”, International Journal of Advances in
Engineering and Technology, Vol 8, pp 1964-1971, May 2015.
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