pushover analysis on reinforced concrete … · pushover analysis on reinforced concrete framed...

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International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 5, May 2018, pp. 1170–1176, Article ID: IJCIET_09_05_131

Available online at http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=9&IType=5

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

© IAEME Publication Scopus Indexed

PUSHOVER ANALYSIS ON REINFORCED

CONCRETE FRAMED MULTILEVEL CAR

PARKING BUILDING USING ETABS

K. Naga Sai Sravya

P.G Student, Structural Engineering, Department of Civil Engineering, Koneru Lakshmaiah

Education Foundation, Vaddeswaram, Guntur, Andhara Pradesh,India

P. Polu Raju

Associate Professor, Department of Civil Engineering, Koneru Lakshmaiah Education

Foundation,Vaddeswaram, Guntur, Andhara Pradesh,India

ABSTRACT

Multilevel car parking building has gained its significance in many urban cities to

reduce the parking issues. Multilevel car parking building carries heavy loads from the

vehicles along with the gravity loads and lateral loads. The present study deals with

modeling and analysis of multilevel car parking building and deliberate the behavior of

multilevel car parking building by non-linear analysis (pushover over analysis) using

ETABS 2016. The major part of any building is to consider the seismic load as an

important aspect. Thus, pushover analysis provides a superior understanding of seismic

performance of the structure and identifies the development of any damage or failure. In

this present study, non-linear static analysis of a five-storied multilevel car parking

building located at different seismic zones of India and compares the results. The

pushover curve and plastic hinge formations in the structure at each zone are explained

clearly with the help of ETABS software. The performance point of pushover analysis has

been varied with respect to building performance levels. Also, the plastic hinge formations

were significant, when seismic zone was increased from II to V. Thus indicates, the

performance of building was predominantly decreases when seismic zone was increased.

Keywords: Multilevel Car parking, Pushover Analysis, Plastic Hinges, Performance

Point, Building Performance Levels

Cite this Article: K. Naga Sai Sravya and P. Polu Raju, Pushover Analysis on Reinforced

Concrete Framed Multilevel Car Parking Building Using Etabs, International Journal of

Civil Engineering and Technology, 9(5), 2018, pp. 1170–1176.

http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=9&IType=5

Pushover Analysis on Reinforced Concrete Framed Multilevel Car Parking Building Using Etabs


1. INTRODUCTION

India, the second most populated country in the world own more than 40 million vehicles.

Since, it has strong domestic market and the growth of population. The growth of the country

economy is stated by the growth of its transport infrastructure. However, the infrastructure

available for vehicles such as street parking is facing a major challenge in most of the Indian

cities. The rapid growth of population in towns, cities and urban centers has been

accomplished by increasing rate of urbanization. The high rate of urbanization has also

affected an increase in the cost of land in the city. The existing towns and cities are lacking

the facilities related to parking, due to which the vehicles are being parked along the highway

sides, residential roadway, pathways and green points of the roads which causes the frequent

traffic jams [1]. Parking in the public areas can be risky with little or no forms of the security

may cause accidents, traffic problems. The valuable time of the workers is lost due to the

traffic problems and if this problem is not rectified at this stage, then it would become a

serious and difficult problem in the future. To decrease the stress of parking and any forms of

insecurity to cars and owners, adequate parking facilities must be provided to meet the

demand of parking which can certainly be possible by construction of multilevel car parking

structure at prominent places.

Multi-Level Car Parking is designed for car parking where there are number of floors on

which vehicles are parked. This type of structure is well known as a parking lot [2]. It

provides ecofriendly operation by giving safety to vehicles and assures high safety & security

for passengers and vehicles. It provides effective maintenance, efficiency, reliability and a

cost-efficient operation. In this type of structure 90% of land space is totally utilization

compared to 67% usage of land in other similar systems by making best use of available land

area above and under the ground with less ecological impact thus reducing chances of theft

and insecurity.

In general, car parking buildings are subjected to the heavy shifting loads of moving

vehicles and must bare related physical stresses. Besides these heavy loads, the structure may

be susceptible to seismic activity thus seismic loads are also considered [3]. Earthquakes

generally occur due to serious tectonic behavior of earth. In recent times, there is a rapid

increase in the occurrence of earthquakes all over the world. The intensity and location of

earthquake is unpredictable as on date which is not necessarily possible by any earthquake

measuring instruments or devices, thus it is necessary to assess the seismic capability of any

building. In India most of urban centers and cities where multilevel car parking is possible can

be designed for both gravity loads and seismic loads to assess the response of structure and

risk management. To assess any reinforced concrete building against failure, a precise

assessment of the crucial behavior of the structure is a well-known analysis popularly called

non-linear static analysis (Pushover Analysis).

Nonlinear static analysis offers an enhancement over linear analysis [4]. This analysis is

very simple and allows inelastic behavior of structure by providing information related to the

strength, deformation, ductility of structure including distribution of demand. This method

adopts a set of static increases in lateral load over the height of the structure. Nonlinear static

analysis allows identifying the critical members which are likely to reach limit states during

the earthquake so that the special care can be paid during the designing and detailing process.

This method involves many assumptions that neglect the variation of loading patterns and

influence the higher modes, effect of resonance. It provides a sensible calculation of global

deformation capacity, particularly for structures that primarily respond in accordance to first

mode of vibration [5]. Since the multilevel car parking structure holds the parking of number

of vehicles it is necessary to verify the response of structure under different loading

conditions. To perform the accurate analysis of the structure a non-linear static analysis was

K. Naga Sai Sravya and P. Polu Raju


chosen which is also called as pushover analysis. Pushover analysis is a popular simplified

tool in computer methods used to evaluate the strength and performance of structure under

seismic activity. Thus, non-linear static analysis (Pushover Analysis) helps to perform

analysis of a multilevel car parking structure and determine the real behavior of structure

during an earthquake. This paper presents the analysis of multilevel car parking structure

located at different seismic zones in India which has designed according to IS: 1893:2002 [6].

2. BUILDING DESCRIPTION

A multilevel car parking structure is a five storey reinforced concrete building with a floor to

floor height of 3.5 meters. This five storey multilevel car parking structure is analyzed at

different seismic zones. The multilevel car parking structure is designed as a frame model as

per Indian standards with joint constraints of ground floor are fixed. A special design of ramp

is made for movement of cars from one floor to another. Table 1 gives the details of plan area,

height of structure and other details of building. Table 2 shows the properties of materials and

sections used to model the structure. Table 3 represents the applied loading details on the

building. Figs. 3 and 4 shows, the plan and elevation of the structure. Fig. 5 show, the 3D

model created in the ETABS.

Table 1 Building Details

Plan Area 104 m × 28.58 m

Height of Ground Floor 3 m

Floor to Floor Height 3.5 m

Total Building Height 17 m

Type of Structure Multilevel Car Parking Structure

Number of Bays in X-direction 16

Number of Bays in Y-direction 13

Support Conditions Fixed

Table 2 Details of Materials and Section Properties

Beam Sizes 1200 mm × 1800 mm (inner and outer beams)

800 mm × 1200 mm (ramp beams)

Column Sizes 1200 mm × 1200 mm (outer columns) 1200 mm × 1500 mm (inner columns) 800 mm × 1000 mm (ramp columns)

Thickness of Slab 200 mm

Grade of Concrete M30 (beams and slab)

M35 (columns)

Grade of Steel TMT 500

Density of Concrete 25 kN/m3

Table 3 Applied Loading Details

Live Load 6 kN/m2

Floor Finishes Load 1.5 kN/m2

Wall Load on Beams 2.28 kN/m

2 (on roof)

16.625 kN/m2 (on floors and ramp)

Earthquake Load As per IS:1893 (Part-1):2002

Importance Factor, I 1.5

Response Reduction Factor, R 5 (SMRF)



Figure 3 Plan of the Building Frame

Figure 4 Elevation of the Building Frame

Figure 5 3D-Building Model in ETABS

3. PUSH OVER ANALYSIS PROCEDURE

In this study a five storey multilevel car parking structure is considered. The modelling and

analysis of structure is carried out in ETABS in accordance with Indian standards that is as

per IS: 456:2000 [7] and IS: 1893(part1):2002 [6]. Initially, it is assumed that the structure

was in zone II. The 3D-model was prepared with properties as mentioned above Table 2. A

special care has been taken in modelling the ramp of the structure which permits the transition

of cars from one floor to other. The generalized task was encountered in the modelling of the

ramp since it is an irregular shape of the structure. After modelling, the structural analysis was

carried in ETABS considering several load cases which include dead load, live load, wind

load and earthquake load. Based on the Indian standard codes the different load combinations

were included. The details of the loadings are already shown in Table 3. The analysis was

carried to determine the response of the structural elements to all possible loadings. Since, the

height of the structure is below 90 m in zone II according to clause 7.8(a) [6], dynamic

analysis is not required in this analysis and to study the real behavior of the structure under all

possible loads, the non-linear static analysis (Pushover Analysis) was adopted. After

assigning all sectional properties to the model, hinges are assigned to the structure. ETABS

has inbuilt FEMA273 and ACT40 hinge properties and it has the capacity to assign hinges to

any type of material. In this study, auto hinge properties are assigned to both beams and

columns. After locating the pushover hinges on the model frame members, pushover analysis

load cases are defined in both X and a Y direction then the pushover analysis has been

performed. During the pushover analysis the model is pushed monotonically increasing lateral

loads based on the seismic zone until the target displacement is reached or till the structure



losses its equilibrium whichever is first. After completion of analysis hinge formations were

noticed in the structure. From which performance levels of building is determined and

pushover curve is obtained. This is a plot between base shear and spectral displacement which

indicates the inelastic behavior of structure. Similarly, the analysis is carried out at different

seismic zones such as III, IV and V having similar plan, material and section properties. The

analysis results obtained at each zone were compared with the help of hinge formations and

pushover curve by determining the performance level of building at each seismic zone.

4. RESULTS AND DISCUSSIONS

The pushover analysis results on Multilevel Car Parking Structure for different seismic zones

were presented in this section. After completion of pushover analysis, the plastic hinges are

formed at different displacement levels. In this, the hinges are formed from step 2 to step 4 of

pushover loading at different seismic zones the hinges formed at critical level of zone V are

shown in Figs. 5 to 8. For the sake of conciseness the formation of hinges after the pushover

analysis at initial zones are not represented here. The hinges are initially formed at the center

of building at both beam and column ends, especially near supports and then in step 3 of

pushover loading the hinges extend to the column ends of ramp and in step 4 the hinges are

formed at beam and column ends of ramp. From the analysis it is observed that the formation

of hinges was significantly increased when seismic zones were changing from II to V. The

hinges were formed at different seismic zones are at a performance level of B to C which

represents the amount of damage to the multilevel car parking structure is limited in all zones

Figure 5 Deformed Shape of Structure at Step 1 in

Zone V

Figure 6 Deformed Shape Of Structure at Step 2

in Zone V

Figure 7 Deformed Shape Of Structure at Step 3

in Zone V

Figure 8 Deformed Shape of Structure at Step 4

in Zone V

From Figs. 9 to 12 shows the performance point where demand curve intersects the

capacity curve at different seismic zones which gives the elastic response the structure during

the ground motion at each specified zone that is from zone II to V and it is concluded that the

design is safe against collapse with sufficient strength and displacements.



Figure 9 Capacity curve -Demand Curve For 5

Storey Building in Zone II

Figure 10 Capacity-Demand Curve For 5 Storey

Building in Zone III

Figure 11 Capacity-Demand Curve For 5 Storey

Building in Zone IV

Figure 12 Capacity-Demand Curve for 5

Storey Building in Zone V

5. CONCLUSION

From this present study the following conclusions are drawn:

1. Multilevel car parking structure is a typical structure, when it comes to parking of

cars and reducing the problems related to road, it provides effective and safe

parking solution to cars.

2. From the hinge formations it is observed that the number of hinges formation was

increased from step to step and subsequently increased from zone II to zone V.

3. From the capacity and demand curves obtained after pushover analysis, it is

observed that the performance point is increased, i.e., the linearity of pushover

curve has been varied when seismic zone changes from II to V.

4. By performing pushover analysis, the complete behavior of MLCP is determined

from the hinge formations and their distribution along the beam and column ends

of the structure including the ramp. The pushover curve and demand curve

obtained in the analysis represents the structure is safe against all possible load

cases.



REFERENCES

[1] Upendra S.D, Rakesh G, and Mukesh P. (2016) “A study of analysis and design of

multilevel parking”, International Journal of Engineering Development and Research

(IJEDR), 4(2):1412-1414.

[2] Radica A.D and Pajgade P.S. (2016) “Design of Multi-Level Car Parking”, International

journal of innovative and emerging research in engineering (IJIERE), 3(1):308-311.

[3] Anthony N.E, Adaramola O, and Michale O. (2015) “Analysis and Design of a Multi-

Storey Helipad-Car Park: A Proposal for Canaan Land”, International Journal of

Innovative Science and Modern Engineering (IJISME), 3(4):43-47.

[4] Chopra A.K, and Goel R.K. (2002) “A modal pushover analysis procedure to estimate

seismic demands for buildings”, Theory and preliminary evaluation, Report No PEER

2001/03, Pacific Earthquake Engineering Research Center, University of California,

Berkeley, USA, 561-582.

[5] Pavan Kumar V.S.R and Polu Raju P (2012) “A Nonlinear Static Analysis of Multistoried

Building”, International Journal of Emerging Trends in Engineering and Development

(IJETED), 4(2): 683-693.

[6] IS 1893-2002: Part-1 “Criteria for Earthquake Resistant Design of Structures”, Bureau of

Indian Standards, New Delhi, 2002.

[7] IS 456:2000, “Plain and Reinforced Concrete-Code of Practice” Bureau of Indian

standards, New Delhi, 1995.

[8] Samir Abdul Baki Jabbar Al-Jassim, Seismic Evaluation of AlNajibiya Bridge Using

Pushover Analysis. International Journal of Civil Engineering and Technology, 8(4),

2017, pp. 550–558.

pushover analysis on reinforced concrete … · pushover analysis on reinforced concrete framed...

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