IRJET- Analysis and Design of High-Rise RC Structure in Different Seismic Zones
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This document analyzes and compares the design of a 15-story reinforced concrete structure with an H-shape in different seismic zones of India. Two models are considered - one with connecting beams between the wings of the H-shape and one without. Both models are modeled and analyzed in STAAD Pro software. The results, including shear forces, bending moments, deflections, and steel reinforcement percentages, are compared for the two models across zones II through V. The analysis shows marginal differences between the two models, with the model without connecting beams performing slightly worse in some parameters. The document concludes that connecting beams have little impact on the structural behavior but can improve construction.
![International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072
© 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3339
τv = [ (Vu) / (bxd) ] = 1.89
τv≥τc
Design reinforcement Vus = [(Vu) – (τcx b x d) ] = 149290
kN
For vertical stirrups Vus = (0.87 fyAsv d) / Sv
Therefore Sv = 129.69 mm i.e 130 mm
Sv shall not be more than
0.75d = 0.75 x 350 = 262.5 mm
300 mm
Minimum shear reinforcement
Minimum shear reinforcement = [(Asv) / (bsv)] ≥ [(0.4) /
(0.87 fy)]
Therefore provide 2 legged 10 mm diameter bars@130mm
center-to-center spacing
Hence the design is matched with output of STAAD.Pro
Fig.9 Beam design output
5.5.2. Design of Column
Manual Design
fck= 25N/mm2 and fy = 500 N/mm2 and Puz = 5551.74
b = 450 mmand d = 600 mm
Puz= [ (0.45fckAc)+ (0.75fyAsc ) ]
By substituting values and solving we get Asc = 6912
mm2
Hence provide main reinforcement of 24 bars of 20 mm
diameter as shown in above figure.
5.5.3. Design of Slab
Size of slab taken = 3.92 x 3.96 m and thickness of slab = 150
mm
Live load = 4kN/m2 and Dead Load = 3.75 + 1 = 4.75 kN/m2
Total load = 8.75 kN/m2 and Factored load = 1.5 x 8.75 =
13.125 kN/m2
Positive bending moment at mid span = [(Wl2) / 12] = 16.81
kN-m and negative bending moment at support = 19.75 kN-
m
Mu limit = [ (1-0.42 ) x fck bd2] = 3.45 bd2
Assuming b = 1000 mm
d = = 67.67 mm
Therefore adopt 28 mm diameter bars as reinforcement
Effective cover = 20 mm and Overall depth = 87.67 mm
Effective depth = 150 – 20 = 130 mm
Mu = 0.87fyAst d (1- )
Substituting values and solving we get Ast = 446.188 mm2
Providing minimum steel of 12% bD = =
186 mm2
Spacing of 10 mm diameter bars = 176.02 mm center-to-
center spacing
Distribution reinforcement
Providing 0.12%of grossarea as distribution reinforcement
Area of steel = (0.12 X 150 X 1000) = 180 mm
Hence provide 6 mm diameter bars @ 150 mm center-to-
center spacing
Check for development length
Ld=[ ] = 402.95 mm and Ldavailable = [ (M1)/V ] + Lo
Mu = 087fyAst d (1- ) = 20.5 X 106 N mm
V = = 25.72 kN
[(M1)/V] + Lo = 727 mm
Ldavailable > Ldreq
Hence design is safe.
Fig.10 Column Design output](https://image.slidesharecdn.com/irjet-v5i3787-190204040803/85/IRJET-Analysis-and-Design-of-High-Rise-RC-Structure-in-Different-Seismic-Zones-4-320.jpg)
IRJET- Analysis and Design of High-Rise RC Structure in Different Seismic Zones
- 1. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3336 Analysis and Design of High-Rise RC Structure in Different Seismic Zones R.Deccan Chronicle1, Mohammed Anwarullah2, Abdul Rashid3, Dr.P.Siva Prasad4 1,2,3 UG Student, Civil Engineering Dept, Dhanekula Institute of Engineering and Technology, Andhra Pradesh, India 4Professor, Civil Engineering Dept, Dhanekula Institute of Engineering and Technology, Andhra Pradesh, India ---------------------------------------------------------------------***-------------------------------------------------------------------- Abstract – One of the major problems that the country facing is the rapidly growing population, which necessities more facilities in the restricted availability of land, which can be solved to a certain extent with the construction of multi- storied buildings, which can serve many people in available limited area. Hence it is the necessary requirement of multi- storied building with all facilities. Hence an attemptismadein the project for analyzing and Designing of themulti-storiedRC building of G+15 in various seismic zones. In this paper we are comparing the H shaped structure in the present seismic zones of India as per IS 1893:2002. We are considering withinthisH-shapedstructure, two models one with connecting beams and the other without connecting beams. Complicated and high-rise structures need very time taking and cumbersome calculations using conventional manual methods. STAAD-Pro provides us a fast, efficient, easy to use and accurate platform for analyzing and designing the structures. The design method used in STAAD-Pro analysis is Equivalent Static Method, conformingtoIndianStandardCode of Practice. STAAD-Pro is a very powerful software tool which can save much time and is very accurate in designs. For the analysis various loads like Dead load, Live load and Seismic load are applied and results are studied for boththemodelsi.e. with and without connecting beams. Key Words: STAAD-Pro, Lateral force, Base Shear, Steel percentage, Maximum Shear force, Maximum Bending Moment, Maximum Deflection, Seismic zones. 1. INTRODUCTION The method of analysis is based on Linear Equivalent Static Method, which gives scope to take valuesfrom IS1893:2002 and performs the analysis. Using this methodwecananalyze the building up to the height of 75 m in Zone II and Zone III and up to the height of 40 m in Zone IV and Zone V. In this paper we have taken two types of column orientations i.e. the column layout varies at stair and lift zone in our paper. Building exceeding the above mentioned heights must be performed for Dynamic analysis, which is more complex when compared with the Static Analysismethod.Baseshears have also been calculated manually. 1.1 Stages in structural design: The process of structural design involves the following stages: Collection of data, Preparation of plan in AutoCAD, Modeling in STAAD.Pro software, computation of loads, Performing analysis, Deriving results and conclusions 2. LITERATURE REVIEW Akash Panchal, Ravi Dwivedi: Seismic analysis of the structures is carried out on the basis of lateral force assumed to act along with the gravity loads. In this project seismic evaluation for the existing residential building is carried out for differentseismic zones by an equivalent static analysis method using STAAD.Pro softwareA G+6 existing RCC framed structure has been analyzed and designed using STAAD-Pro V8i. Narla Mohan, A.Mounika Vardhan: The objectives were how the seismic evaluation of a building should be carried out. To study the behaviour of a building under the action of seismic loads and wind loads. To compare various analysis results of building under zone II, III, IV and zone V using ETABS Software. The building model in the study has twenty storey’s with constant storey height of 3m. Five models are used to analyze with constant bay lengths and the number of Bays and the bay width along two horizontal directions are kept constant in each model for convenience. Tiriveedhi Sai Krishna, V.Srinivasa Rao: The analysis of multistoried buildings is explained in two ways in this project i.e. with earth quake and without earthquake. In this Report they have Analyze base shears for structure in manually in all seismic zones by calculating the gravity loads using IS 1893- 2002.This study addresses the performance and the variation of steel quantity for the whole structure in seismic zones by using STAAD.Pro software.They calculated B.M. and S.F. in the beams, axial loads in columns and compared the axial loads in different seismic zones 3. METHODOLOGY DRAWING UP THE PLAN The plan of both the models have to be drawn using AutoCAD software.
- 2. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3337 MODELING IN STAAD.PRO SOFTWARE Both the models have to be modeled. CONSIDERING LOADS The loads have been considered based on manual calculations as per IS codes. ANALYSIS Analysis of RCC framed structure after assigning the loads and Shear Force, Bending Moment and Deflections calculations. DESIGN Design of beam,column and slab GEOMETRIC PARAMETERS Beam = 350 x 350 mm Column Type 1 = 450 x 600 mm Column Type 2 = 600 x 450 mm Depth of Slab = 150 mm 4. OBJECTIVES To study the behavior of structure in various seismic zones. To study the variations in parameters such asShear Force, Bending moment and Displacement in all seismic zones as per IS: 1893-2002. To compare the structure in two models of H shaped Structure without connecting beams and with the connecting beam. 5. MODELING, ANALYSIS AND DESIGN 5.1 Development of Plan Fig.1 Model-I without Connecting Beams Fig.2 Model-II with connecting beams 5.2 Creation of Structure Fig.3 Column layout excluding stairs and lift zone Fig.4 Column layout at stairs and lift zone
- 3. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3338 5.3 Load Considerations 5.3.1.Dead Loads The Dead loads have been considered as per IS 875:1987-Part I. Load 3.75 kN/m2 is defined in Global Y direction calculated as per dimensions. Load intensity 11.73 kN/m has applied for floors up to 14th floor and intensity 5.86 kN/m has applied for top floor with 3.45kN/m as parapet wall. All the forces have been taken in Global Y direction. 5.3.2. Live Loads The Live loads have been considered as per IS 875:1987-Part II. Live Load intensity 4 kN/m2 has been assigned from base to 14th floor and 2 kN/m2 has been assigned on 15thfloor.All the forces have been taken in Global Y direction only. 5.3.3. Seismic Load Combinations The load combination cases have been derived from IS 1893:2002, Clause 6.3.1.2 1.5 (Dead Load + Live Load) 1.2 (Dead Load + LiveLoad + EarthquakeLoad) 1.2 (Dead Load + Live Load - Earthquake Load) 1.5 (Dead Load + Earthquake Load) 1.5 (Dead Load - Earthquake Load) 0.9 (Dead Load) + 1.5 (Earthquake Load) 0.9 (Dead Load) - 1.5 (Earthquake Load) Fig.5 Structure after applying all the loads 5.4 Generation of Analysis Results The analysis has been done by using STAAD.Pro software and the following figures show the derived Shear Force, Bending moment and Deflection variations. Fig.6 Shear Force Diagram in Zone V from +Z view Fig.7 Bending Moment Diagram in Zone V from +Z view Fig.8 Deflection Diagram in Zone V from +Z view 5.5 Design 5.5.1. Design of Beam Manual calculation for beam Cross section of beam: b x d = 350mm x 350 mm Ast = 2520 mm2 (100xAst) / (bxd) = 1.17 Vertical shear force = Vu =232.591kN τc = 0.29 N/mm2 (from table 19 of IS 456 200)
- 4. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3339 τv = [ (Vu) / (bxd) ] = 1.89 τv≥τc Design reinforcement Vus = [(Vu) – (τcx b x d) ] = 149290 kN For vertical stirrups Vus = (0.87 fyAsv d) / Sv Therefore Sv = 129.69 mm i.e 130 mm Sv shall not be more than 0.75d = 0.75 x 350 = 262.5 mm 300 mm Minimum shear reinforcement Minimum shear reinforcement = [(Asv) / (bsv)] ≥ [(0.4) / (0.87 fy)] Therefore provide 2 legged 10 mm diameter bars@130mm center-to-center spacing Hence the design is matched with output of STAAD.Pro Fig.9 Beam design output 5.5.2. Design of Column Manual Design fck= 25N/mm2 and fy = 500 N/mm2 and Puz = 5551.74 b = 450 mmand d = 600 mm Puz= [ (0.45fckAc)+ (0.75fyAsc ) ] By substituting values and solving we get Asc = 6912 mm2 Hence provide main reinforcement of 24 bars of 20 mm diameter as shown in above figure. 5.5.3. Design of Slab Size of slab taken = 3.92 x 3.96 m and thickness of slab = 150 mm Live load = 4kN/m2 and Dead Load = 3.75 + 1 = 4.75 kN/m2 Total load = 8.75 kN/m2 and Factored load = 1.5 x 8.75 = 13.125 kN/m2 Positive bending moment at mid span = [(Wl2) / 12] = 16.81 kN-m and negative bending moment at support = 19.75 kN- m Mu limit = [ (1-0.42 ) x fck bd2] = 3.45 bd2 Assuming b = 1000 mm d = = 67.67 mm Therefore adopt 28 mm diameter bars as reinforcement Effective cover = 20 mm and Overall depth = 87.67 mm Effective depth = 150 – 20 = 130 mm Mu = 0.87fyAst d (1- ) Substituting values and solving we get Ast = 446.188 mm2 Providing minimum steel of 12% bD = = 186 mm2 Spacing of 10 mm diameter bars = 176.02 mm center-to- center spacing Distribution reinforcement Providing 0.12%of grossarea as distribution reinforcement Area of steel = (0.12 X 150 X 1000) = 180 mm Hence provide 6 mm diameter bars @ 150 mm center-to- center spacing Check for development length Ld=[ ] = 402.95 mm and Ldavailable = [ (M1)/V ] + Lo Mu = 087fyAst d (1- ) = 20.5 X 106 N mm V = = 25.72 kN [(M1)/V] + Lo = 727 mm Ldavailable > Ldreq Hence design is safe. Fig.10 Column Design output
- 5. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3340 6. Results 6.1 Shear force Variations In beams In columns 6.2 Bending moment Variations In beams In columns 6.3 Deflection Variations In beams In columns 6.4 Percentage of Reinforcement Variations In columns 7. CONCLUSIONS Shear Force variations: Table.1 Shear Force values in Beams and Columns Zones SF in Beams Variati on in % SF in Columns Vari ation in % Model- I Model- II Model-I Model- II II 127.3 2 125.1 1.74 76.54 76.734 0.25 III 127.3 2 125.1 1.74 112.442 112.85 0.36 IV 168.4 2 167.4 0.6 160.31 161.1 0.5 V 234.1 232.6 0.64 232.1 233.241 0.5
- 6. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3341 The above table.1 shows the comparative results of Shear Forces in beams are likely varying as 1.74, 1.74, 0.6and 0.64 in % and in columns are 0.25, 0.36, 0.5 and 0.5 in % for Zones II, III, IV and V respectively subjected loadings as per IS 1893-2002. Where Model-I is H-shaped Structure with Connecting Beams and Model-II is without Connecting beams. Bending Moment variations: Table.2 Bending Moment values in Beams and Columns Zone s BM in Beams Variati on in % BM in Columns Vari atio n in % Model -I Model- II Model- I Model- II II 172.3 5 168.68 2.13 164.7 112.1 31.9 III 202.2 197.92 2.12 259.1 257.1 0.78 IV 245.6 251.76 2.51 383.5 380.5 0.77 V 360.2 2 358.1 0.6 570 565.6 0.77 The above table.2 showsthe comparative results of bending moment in beams are likely varying as 2.13, 2.12, 2.51 and 0.6 in % and in columns are 31.9, 0.78, 0.77 and 0.77 in%for Zones II, III, IV and V respectively subjected loadings as per IS: 1893-2002 for two models. Deflection variations: Table.3 Deflection in Beams and Columns Zones Beams Variati on in % Columns Vari ation in % Model- I Model- II Model-I Model- II II 8.062 8.048 0.17 0.415 0.41 1.68 III 8.062 8.048 0.17 0.665 0.643 3.31 IV 8.062 8.048 0.17 0.972 0.956 1.65 V 8.912 8.887 0.28 1.45 1.43 1.65 5 Form the table 3 it is found that variations in deflections in beams are 0.17, 0.17, 0.17 and 0.28 in % and in columns are 1.68, 3.31, 1.65 and 1.655 in % for Zones II, III, IV and V respectively when subjected loadings as per IS: 1893-2002. Percentage of Reinforcement: From table.4 it is found that area of steel in varying as 22.85%, 18.75%, 12.98% and 11.7% for two models when subjected to loadings as per IS: 1893-2002, for zones II, III, IV and V respectively. Table.4 Comparison of Reinforcement in two models Zones Area of Steel, mm2 Variation in % Model-I Model-II II 2800 2160 22.85 III 3456 2808 18.75 IV 5030 4377 12.98 V 7986 7051 11.7 8. REFERENCES 1. Akash Panchal & Ravi Dwivedi, “Analysis and Design of G+6 Building in Different Seismic Zones of India”, International Journal for Innovative Research in Science, Engineering and Technology , Vol. 6, Issue 7, July 2017. 2. Narla Mohan, A.MounikaVardhan “Analysis Of G+20 RC Building In Different Zones Using ETABS”, International Journal forProfessionalEngineeringand Studies, Volume VIII /Issue 3 / MAR 2017. 3. TiriveedhiSaikrishna&V.Srinivasa Rao “Earthquake Analysis And Design Of Multi-storied Building For Different Zones In India ”, International Journal for Technical Research and Education ,Volume 4, Issue 4, December-2016. 4. Earthquake resistant design of structurestextbookby Pankaj Agarwal. 5. Earthquake behaviour of buildings textbook by C.V.R.Murty,RupenGoswami, A.R.Vijayanarayanan, Vipul V. Mehta. 6. Eartquake resistant building by M.Y.H.Bangash 7. IS 1893-2002,Criteria for Earthquake Resistant Design of Structures,Part 1 : General provisions and Buildings (Fifth Revision). 8. IS 456-2000 Plain reinforced concrete-Code of practice (Fourth revision). 9. IS 875 (Part 1) Code of practice for design loads (Other than Earthquake) for buildingsand structures. Part 1: Dead loads – Unit weight of building materials and stored materials (Second revision). 10. IS 875 (Part 2) Code of practice for design loads (Other than Earthquake) for buildingsand structures. Part 2: Imposed loads (Second revision).