Seismic Response of Segmental Building with Triple...

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].




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




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




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




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




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




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




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 TFPB building with TFPB






Figure 17. Hysteresis behavior of segmental Figure 18. Hysteresis behavior of segmental







Figure 21. Hysteresis behavior of segmental Figure 22.Hysteresis behavior of segmental







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.

Seismic Response of Segmental Building with Triple...

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