IRJET-Comparative Study of Equivalent Static Analysis and Response Spectrum Analysis on Conventional Slab &Flat Slab With or Without Shear Wall using STADD. PRO
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This document compares the results of equivalent static analysis and response spectrum analysis of buildings with different slab and shear wall configurations (conventional slab, flat slab, and flat slab with shear wall). A commercial building with G+5, G+10, and G+15 floors is modeled and analyzed using the STAAD Pro software. Parameters such as base shear, story drift, displacement, shear force, and bending moment are compared between the two analysis methods. The response spectrum analysis generally yields lower parameter values than the equivalent static analysis.
![International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072
© 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2572
Comparative Study of Equivalent Static Analysis and Response
spectrum analysis on conventional slab & Flat Slab with or without
shear wall Using STADD. PRO
Yogita Tripathi 1, Asst. Prof Ravi Dwivedi2
1PG Student in structural engineering, Malwa Institute of Science& Technology M.P. India
2Asst.Professor & Head, Department of Civil engineering, Malwa Institute of Science& Technology M.P. India
---------------------------------------------------------------------***---------------------------------------------------------------------
Abstract – As we know flat slab building structures are
significantly more flexible than traditional concrete
frame/wall or frame structures, thus becoming more
vulnerable to seismic loading. To improve the performance of
building having flat slabs under seismic loading, provision of
flat slab with shear wall is proposed in the present work. In
this paper a commercial building with G+5, G+10 and G+15
floors is considered for the seismic analysis using response
spectrum method. The results are compared with equivalent
static method. The software usedfortheanalysisisSTAAD. Pro
V8I SS6. In this work the seismic zone is considered to be Zone
III, soil type hard. The results generated from both themethod
were compared considering the parameters such as base
shear, maximum displacement, maximum shear force and
bending moment and storey drifts.
Key Words: Response spectrum, equivalent static
analysis, STADD.Pro, Base shear, Flat slab, Shear wall,
seismic loading.
1. INTRODUCTION
Earthquake or seismic analysis is a subset of structural
analysis which involves the calculation of the response of a
structure subjectedtoearthquakeexcitation.Variousseismic
data are necessary to carry out the seismic analysis of the
structures .The object of the present work is to compare the
behavior of multi-storey buildings having flat slabs and flat
slab with shear wall on the performance of these threetypes
of buildings under seismic forces.
1.1 LITERATURE REVIEW
Anuja Walvekar, H.S.Jadhav (2015) Investigatedthe effect
of flat slab building with and without shear wall and the
seismic behavior of high rise building with different
positions of shear wall. For that, 15 story models were
selected and the effect of different locations of shear wall on
high rise structure, linear dynamic analysis (response
spectrum analysis) using software ETABs was carried out.
Seismic parameters like time period, base shear, storey
displacement and storey drift are checked out. [6]
Raghavendra Rao, Dr.M Rame Gowda (2015)Carriedout
the study of characteristic seismic behavior of flat slab
buildings. a residential building with G+10 floors is
considered for the seismic analysisusingresponsespectrum
method. The results are compared with equivalent static
method. The software used for the analysis is ETABS
2015.0.0. Drift and displacement results obtained by ESA
are greater than the results obtained by RSA. [10]
R.S.More, V. S. Sawant (2015) gave the guidelines for
analysis of flat slab taking into account space crunch, height
limitations and other factors, deviations from a regular
geometry and regular layout andalsobehaviorand response
of flat slabs during earthquake. [9]
1.2 Method of seismic analysis
In the equivalent static method, the lateral force equivalent
to the design basis earthquake is applied statically. The
equivalent lateral forces at each storey level are applied at
the floor level. The base shear (V = VB) is calculated as per
Clause 7.5.3 of IS 1893: 2002.
The response spectrum is a plot of the maximum response
(maximum displacement, velocity, acceleration or anyother
quantity of interest) to a specified load function for all
possible single degree-of-freedom systems. The abscissa of
the spectrum is the natural period (or frequency) of the
system and the ordinate is the maximum response. It is also
a function of damping. Fig. 3.1 shows the design response
spectrum given in IS 1893: 2002 for a 5% damped system.
According to IS 1893: 2002, high rise and irregularbuildings
must be analyzed by the response spectrum method.
1.3 Objectives of the Present Work
i. To perform static and dynamic analysis of multi-
storeyed RCC buildings in conventional slab, flat
slab with shear wall& without shear wall (G+5,
G+10, G+15 Storey) using Response Spectrum
Analysis and Equivalent StaticAnalysis,considering
earthquake Zones(III) as per the Indian Standard
code of practice IS 1893-2002 part-I: Criteria for
Earthquake resistant structure (Zone III).
ii. To find the relationship between Equivalent static
analysis and Response spectrum analysis method.](https://image.slidesharecdn.com/irjet-v5i6482-180814112155/85/IRJET-Comparative-Study-of-Equivalent-Static-Analysis-and-Response-Spectrum-Analysis-on-Conventional-Slab-Flat-Slab-With-or-Without-Shear-Wall-using-STADD-PRO-1-320.jpg)
IRJET-Comparative Study of Equivalent Static Analysis and Response Spectrum Analysis on Conventional Slab &Flat Slab With or Without Shear Wall using STADD. PRO
- 1. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2572 Comparative Study of Equivalent Static Analysis and Response spectrum analysis on conventional slab & Flat Slab with or without shear wall Using STADD. PRO Yogita Tripathi 1, Asst. Prof Ravi Dwivedi2 1PG Student in structural engineering, Malwa Institute of Science& Technology M.P. India 2Asst.Professor & Head, Department of Civil engineering, Malwa Institute of Science& Technology M.P. India ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract – As we know flat slab building structures are significantly more flexible than traditional concrete frame/wall or frame structures, thus becoming more vulnerable to seismic loading. To improve the performance of building having flat slabs under seismic loading, provision of flat slab with shear wall is proposed in the present work. In this paper a commercial building with G+5, G+10 and G+15 floors is considered for the seismic analysis using response spectrum method. The results are compared with equivalent static method. The software usedfortheanalysisisSTAAD. Pro V8I SS6. In this work the seismic zone is considered to be Zone III, soil type hard. The results generated from both themethod were compared considering the parameters such as base shear, maximum displacement, maximum shear force and bending moment and storey drifts. Key Words: Response spectrum, equivalent static analysis, STADD.Pro, Base shear, Flat slab, Shear wall, seismic loading. 1. INTRODUCTION Earthquake or seismic analysis is a subset of structural analysis which involves the calculation of the response of a structure subjectedtoearthquakeexcitation.Variousseismic data are necessary to carry out the seismic analysis of the structures .The object of the present work is to compare the behavior of multi-storey buildings having flat slabs and flat slab with shear wall on the performance of these threetypes of buildings under seismic forces. 1.1 LITERATURE REVIEW Anuja Walvekar, H.S.Jadhav (2015) Investigatedthe effect of flat slab building with and without shear wall and the seismic behavior of high rise building with different positions of shear wall. For that, 15 story models were selected and the effect of different locations of shear wall on high rise structure, linear dynamic analysis (response spectrum analysis) using software ETABs was carried out. Seismic parameters like time period, base shear, storey displacement and storey drift are checked out. [6] Raghavendra Rao, Dr.M Rame Gowda (2015)Carriedout the study of characteristic seismic behavior of flat slab buildings. a residential building with G+10 floors is considered for the seismic analysisusingresponsespectrum method. The results are compared with equivalent static method. The software used for the analysis is ETABS 2015.0.0. Drift and displacement results obtained by ESA are greater than the results obtained by RSA. [10] R.S.More, V. S. Sawant (2015) gave the guidelines for analysis of flat slab taking into account space crunch, height limitations and other factors, deviations from a regular geometry and regular layout andalsobehaviorand response of flat slabs during earthquake. [9] 1.2 Method of seismic analysis In the equivalent static method, the lateral force equivalent to the design basis earthquake is applied statically. The equivalent lateral forces at each storey level are applied at the floor level. The base shear (V = VB) is calculated as per Clause 7.5.3 of IS 1893: 2002. The response spectrum is a plot of the maximum response (maximum displacement, velocity, acceleration or anyother quantity of interest) to a specified load function for all possible single degree-of-freedom systems. The abscissa of the spectrum is the natural period (or frequency) of the system and the ordinate is the maximum response. It is also a function of damping. Fig. 3.1 shows the design response spectrum given in IS 1893: 2002 for a 5% damped system. According to IS 1893: 2002, high rise and irregularbuildings must be analyzed by the response spectrum method. 1.3 Objectives of the Present Work i. To perform static and dynamic analysis of multi- storeyed RCC buildings in conventional slab, flat slab with shear wall& without shear wall (G+5, G+10, G+15 Storey) using Response Spectrum Analysis and Equivalent StaticAnalysis,considering earthquake Zones(III) as per the Indian Standard code of practice IS 1893-2002 part-I: Criteria for Earthquake resistant structure (Zone III). ii. To find the relationship between Equivalent static analysis and Response spectrum analysis method.
- 2. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2573 1.4 Model Description A building plan was taken in seismic zone III for seismic analysis of the building with conventional slab, flat slab and shear wall. Building details are given below. Table-1: Building details Particulars Details Plan Size 43.840 m x 19.500m Number of Floors G+5, G+10, G+15 Building Type COMMERCIAL Storey Height 19.50m,37m,54.5m Soil Type Hard Soil (Type III) Steel Grade Fe 415 Concrete Grade M 25 Seismic Zone III Response Reduction Factor 3 Importance Factor 1 Exterior Column Size 400mm x6500 mm Interior Column Size 400mm x 500mm Beam Size 300mm x 450 mm Slab Thickness 150 mm Slab Thickness 150 mm Shear Wall thickness 230 mm Live Load on floor 2 KN/m2 Live Load on terrace 1.5 KN/m2 Terrace finish 1KN/m2 Floor Finish 1KN/m2 Fig. 1 Plan for building Table -2: Details of Models Model Number Slab Model 1 G+5 CS Model 2 G+10 CS Model 3 G+15 CS Model 4 G+5 FS Model 5 G+10 FS Model 6 G+15 FS Model 7 G+5 FS WITH SW Model 8 G+10 FSWITH SW Model 9 G+15 FS WITH SW 2. RESULTS AND DESCUSSION The results obtained from the STAAD Pro. analysis of G+5, G+10 & G+15 model for ESA and RSA methods are tabulated and discussed for the parameters such as base shear, maximum storey drift, displacement, shear force and bending moment. The comparison between ESA and RSA methods are shown and reported. 2.1 Base shear Base shear is the maximum expected lateral force that will occur due to seismic ground acceleration at the base of the structure. The base shear, or earthquake force, is given by the symbol “VB”. Table -3: Base shear for ESA and RSA method MODELS ESA RSA Model 1 1910 KN 1910 KN Model 2 2182 KN 2160 KN Model 3 2380 KN 2372 KN Model 4 1809 KN 1809 KN Model 5 2067 KN 2064 KN Model 6 2255 KN 2248 KN Model 7 1808 KN 1808 KN Model 8 2072 KN 2069 KN Model 9 2263 KN 2252 KN
- 3. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2574 0 500 1000 1500 2000 2500 Model1 Model2 Model3 Model4 Model5 Model6 Model7 Model8 Model9 ESA RSA Chart -1: Base shear for ESA and RSA method Base shear value for different slab condition (CS, FS, FSSW) in G+5, G+10 and G+15 are 0% to 1% less respectively, in RSA than ESA. 2.2 Story drift Storey drift is the drift of one level of a multistory building relative to the level below. Inter-storey drift isthedifference between the roof and floor displacements of any given story as the building sways during the earthquake, normalized by the story height. The factor is defined as the ratio of the story shear force when story collapse occurs to the story shear force when total collapse occurs. Through a series of dynamic analyses, simple equations are provisionally proposed to calculate the necessary story shear safety factorthatcanbeusedtoprevent story collapse. Table -4: Story drift for ESA and RSA method MODELS ESA RSA X(m) Z(m) X(m) Z(m) Models - 1 0.00028 0.00020 0.00019 0.00005 Models - 2 0.00034 0.00026 0.00030 0.00005 Models - 3 0.00039 0.00032 0.00036 0.00010 Models - 4 0.00062 0.00072 0.00015 0.00004 Models - 5 0.00072 0.00098 0.00044 0.00013 Models- 6 0.00076 0.00110 0.00064 0.00024 Models- 7 0.00075 0.00140 0.00021 0.00009 Models- 8 0.00040 0.00058 0.00032 0.00011 Models- 9 0.00095 0.00357 0.00077 0.00101 0 0.001 0.002 0.003 0.004 Model1 Model2 Model3 Model4 Model5 Model6 Model7 Model8 Model9 X-ESA Z-ESA X-RSA Z-RSA Chart -2: Story drift for ESA and RSA method Storey drift value along x axis for G+5 withdifferentslab condition (CS, FS, FSSW) are 32%, 76%& 72% less respectively, in RSA than ESA. Storey drift value along z axis for G+5 with differentslab condition (CS, FS, FSSW) are 75%, 81%& 69% less respectively, in RSA than ESA. Storey drift value along x axis for G+10 with different slab condition (CS, FS, FSSW) are 76%, 39%& 16% less respectively, in RSA than ESA. Storey drift value along z axis for G+10 with different slab condition (CS, FS, FSSW) are 94%, 87%& 78% less respectively, in RSA than ESA. Storey drift value along x axis for G+15 with different slab condition (CS, FS, FSSW) are 72%, 20%& 19% less respectively, in RSA than ESA.. Storey drift value along z axis for G+15 with different slab condition (CS, FS, FSSW) are 94%, 81%& 72% less respectively, in RSA than ESA. 2.3 Shear force Shearing forces are unaligned forces pushing one part of a body in one specific direction, and another part of the body in the opposite direction. When the forces are aligned into each other, they are called compression forces. Table -5: Shear force for ESA and RSA method MODELS ESA RSA X(KN) Z(KN) X(KN) Z(KN) Model 1 240 22 210 9 Model 2 349 26 318 10 Model 3 416 30 370 11 Model 4 265 36 214 16 Model 5 436 59 326 14
- 4. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2575 Model 6 727 75 467 12 Model 7 753 47 649 30 Model 8 1307 87 1278 31 Model 9 1505 107 1497 34 0 200 400 600 800 1000 1200 1400 1600 Model1 Model2 Model3 Model4 Model5 Model6 Model7 Model8 Model9 X ESA Z ESA X RSA Z RSA Chart -3: max. shear force for ESA and RSA method Shear force value along x axis for G+5 with differentslab condition (CS, FS, FSSW) are 13%, 19%& 14% less respectively, in RSA than ESA. Shear force value along z axis for G+5 with differentslab condition (CS, FS, FSSW) are 59%, 56%& 36% less respectively, in RSA than ESA. Shear force value along x axis for G+10 with different slab condition (CS, FS, FSSW) are 9%, 25%& 2% less respectively, in RSA than ESA. Shear force value along z axis for G+10 with different slab condition (CS, FS, FSSW) are 62%, 76%& 64% less respectively, in RSA than ESA. Shear force value along x axis for G+15 with different slab condition (CS, FS, FSSW) are 11%, 36%& 1% less respectively, in RSA than ESA. Shear force value along z axis for G+15 with different slab condition (CS, FS, FSSW) are 63%, 84%& 68% less respectively, in RSA than ESA. 2.4 Bending moment Bending Moment is the torque that keeps a beamtogether. It is found by cutting the beam, then calculating the MOMENT needed to hold the left (or right) half of the beam stationary. If this is done for the other (left) side you should get the same answer - but opposite direction. Table -6: Bending moment for ESA and RSA method MODELS ESA RSA X (KN- m) Z (KN- m) X (KN- m) Z( KN- m) Model 1 4 54 3 52 Model 2 5 65 4 62 Model 3 5 71 4 69 Model 4 14 70 12 66 Model 5 10 113 9 94 Model 6 7 152 6 107 Model 7 14 40 9 28 Model 8 12 79 11 65 Model 9 11 129 10 100 0 50 100 150 200 X ESA Z ESA X RSA Z RSA Chart -4: max. Bending moment for ESA and RSA method Bending moment value along x axis for G+5 with different slab condition (CS, FS, FSSW) are 25%, 14%&36% less respectively, in RSA than ESA. Bending moment Shear force value along z axis for G+5 with different slab condition (CS, FS, FSSW) are 4%, 6%& 30% less respectively, in RSA than ESA. Bending moment value along x axis for G+10 with different slab condition (CS, FS, FSSW) are 20%, 10%& 8% less respectively, in RSA than ESA. Bending moment value along z axis for G+10 with different slab condition (CS, FS, FSSW) are 5%, 17%& 18% less respectively, in RSA than ESA. Bending moment value along x axis for G+15 with different slab condition (CS, FS, FSSW) are 20%, 36%& 1% less respectively, in RSA than ESA. Bending moment value along z axis for G+15 with different slab condition (CS, FS, FSSW) are 3%, 30%& 22% less respectively, in RSA than ESA.
- 5. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2576 2.5 Storey Displacement Storey displacement is displacement with respect to base of the structure. Table -7: Story displacement for ESA and RSA method MODELS ESA RSA X(mm) Z(mm) X(mm) Z(mm) Model 1 14.097 10.023 12.612 1.777 Model 2 29.575 24.783 25.161 1.181 Model 3 48.397 42.561 38.885 1.247 Model 4 38.440 39.804 38.604 12.716 Model 5 68.184 97.552 59.994 12.797 Model 6 102.375 155.785 87.530 14.407 Model 7 31.100 38.964 26.143 23.176 Model 8 48.654 86.298 47.385 11.665 Model 9 74.475 126.093 69.127 9.068 0 50 100 150 200 X ESA Z ESA X RSA Z RSA Chart -5: max. Displacement for ESA and RSA method Storey displacement value along x axis for G+5 with different slab condition (CS, FS, FSSW) are 11%, 1%& 16% less respectively, in RSA than ESA. Storey displacement value along z axis for G+5 with different slab condition (CS, FS, FSSW) are 82%, 68%&41% less respectively, in RSA than ESA. Storey displacement value along x axis for G+10 with different slab condition (CS, FS, FSSW) are 15%,12%&3% less respectively, in RSA than ESA. Storey displacement value along z axis for G+10 with different slab condition (CS, FS, FSSW) are 95%, 87%& 86% less respectively, in RSA than ESA. Storey displacement value along x axis for G+15 with different slab condition (CS, FS, FSSW) are 20%, 15%& 7% less respectively, in RSA than ESA. Storey displacement value along z axis for G+15 with different slab condition (CS, FS, FSSW) are 97%, 91%& 90% less respectively, in RSA than ESA. (NOTE): ESA = Equivalent Static Analysis RSA = Response Spectrum Analysis CS = Conventional slab FS = Flat slab FSSW=Flat slab with shear wall 3. CONCLUSIONS From the results obtained as above, the following conclusions are drawn: 1. The seismic analysis of reinforced concrete frame structure is done by both static and dynamic analysis to determine and compare the base shear, it has been found that the difference between varies from 0-1%. 2. In buildings with flat slab, storey drift is significantly more as compared to CS slab buildings and approximately same as FS with shear wall which leads to the development of additional moment causedbydriftwhichisalso considered this while designing the columns. 3. The values of storey drift for all the stories are found to be within the permissible limit i.e. not more than 0.004 times to storey height according to IS 1893 : 2002 (Part I) . 4. Building saving flat slab with shear wall experience maximum force and bending moment as compared to respective buildings with only flat slab and conventional slab. 5. Compared to the building with flat slab, maximum displacement of CS and FS are less than that in the shear wall slab building. 6. Dynamic analysis gives lesser values for all parameters than static analysis. Hence, dynamic analysis is economical. 7. Drift and displacement results obtained byESA are greater than the results obtained by RSA 8. From the analysis results for both ESA and RSA the storey displacement and storey drift is more along the shorter span i.e., in X-direction. 9. Base shear of conventional R.C.C building is greater than the flat slab building.
- 6. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 06 | June-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 2577 ACKNOWLEDGEMENT I would like to thank Mr. Ravi Dwivedi, Head of Civil Engineering Department for providing me direct and indirect help in completion of my research work. My special thanks go to my husband Mr. Ashish Dwivedi for constantly boosting me for the completion of the research work. REFERENCES 1. Vishesh P. Thakkar Anuj K. Chandiwala Unnati D. Bhagat “Comparative Study of Seismic Behavior of Flat Slab and Conventional RC Framed Structure” International Journal of Engineering Research & Technology (IJERT) http://www.ijert.org. ISSN: 2278-0181 IJERTV 6IS040739, Vol. 6 Issue 04, April-2017 PP. 923-929. 2. Athira M. V 1, Sruthi K Chandran “Significance of shear wall in flat slab multi storied building” International Research Journal of Engineeringand Technology (IRJET) e-ISSN: 2395 -0056 Volume: 04 Issue: 02 | Feb -2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1159 3. Mohammed Fatir, M.H.Kolhar, Anjum Algur “Relative study of seismic analysis between flat slaband grid slab of rcstructures with different masonry infills in two different zones”IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 , pISSN:2321- 7308,Volume:05 Issue: 07Jul-2016, Available @ http://ijret.esatjournals.org, PP.324-332 4. SHAIK TAHASEEN “shear wall design for g+8 floors residential building” International Journal of Engineering Research-Online A Peer Reviewed International Journal Articles available online http://www.ijoer.in, Vol.3., Issue.6., 2015 (Nov.- Dec.,)ISSN: 2321-7758 ,PP. 37-43 5. Salman I. Khan and Ashok R. Mundhada “Comparative study of Seismic Performance of multistoried R.C.C buildings with Flat slab & Grid slab” International Journal of Current Engineering and Technology E-ISSN 2277 – 4106, P-ISSN 2347 – 5161 Vol.5, No.3 (June 2015) , PP. 1666-1672. 6. Anuja Walvekar1, H.S.Jadhav “parametric study of flat slab building with and without shear wall to seismic performance” IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 Volume: 04 Issue: 04|Apr-2015,Available@http://www.ijret.org,PP. 601-607 7. Pradip S. Lande, Aniket B. Raut “Seismic Behavior of Flat Slab Systems” Journal of Civil Engineering and Environmental Technology .Print ISSN: 2349- 8404; Online ISSN: 2349-879X; Volume 2,Number 10; April-June, 2015 pp. 7-10 8. Raghavendra Rao K1, Dr.M Rame Gowda2 “Comparative Study of Equivalent Static Analysis and Response spectrum analysisonFlatSlabUsing Etabs” International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056 Volume: 03 Issue: 08|Aug -2016 www.irjet.net p-ISSN: 2395-0072