PLANNING, ANALYSIS AND DESIGN OF A SHOPPING MALL A PROJECT REPORT Submitted by R. ANEES FATHIMA 110119103002 S.A.C. WASIF MUKTHAR 110119103026 N. SAIFULLAH 110119103304 in partial fulfillment for the award of the degree of BACHELOR OF ENGINEERING IN CIVIL ENGINEERING AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING ANNA UNIVERSITY : CHENNAI 600025 DECEMBER - 2022 ANNA UNIVERSITY : CHENNAI 600025 BONAFIDE CERTIFICATE Certified that this project report “PLANNING, ANALYSIS & DESIGN OF A SHOPPING MALL” is the bonafide work of “R. ANEES FATHIMA (110119103002) ; S.A.C. WASIF MUKTHAR (110119103026) ; N. SAIFULLAH (110119103304)” who carried out the project work under my supervision. SIGNATURE SIGNATURE Prof. Dr. M. AFZAL ALI BAIG, M.E., Ph.D., M.I.S.T.E., Er. Mr. D. Prakash, M.E., Assistant Professor, HEAD OF THE DEPARTMENT SUPERVISOR DEPARTMENT OF CIVIL ENGINEERING DEPARTMENT OF CIVIL ENGINEERING AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING MUTHAPUDUPET, AVADI IAF CHENNAI – 600055. AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING MUTHAPUDUPET, AVADI IAF CHENNAI – 600055. TABLE OF CONTENTS CHAPTER NO. TITLE PAGE NO. 1 ABSTRACT 01 2 LIST OF SYMBOLS 02 3 INTRODUCTION 03 4 ANALYSIS 05 5 DESIGN FLAT SLAB (TERRACE) 09 FLAT SLAB (FLOORS) 11 III. TWO WAY SLAB 15 IV. EDGE BEAM 17 AXIALLY LOADED COLUMN 19 UNI-AXIALLY LOADED COLUMN 21 BI-AXIALLY LOADED COLUMN 22 CIRCULAR COLUMN 23 DOG LEGGED STAIRCASE 25 RETAINING WALL 27 ISOLATED COLUMN FOOTING 30 I. II. V. VI. VII. VIII. IX. X. XI. 6 CONCLUSION 33 7 REFERENCE 34 ABSTRACT Report to accompany the Planning, Analysis & Design of a “SHOPPING MALL” The main of this project is to design a shopping mall, which is designed in achievement of an acceptable probability that the structure being designed within appropriate factor of safety and perform satisfactorily during their intended life. This design is done according to the limit state method and conforming to the Indian standard code IS 456-2000 & SP 16. The beam and column are designed by considering the maximum loading condition and maximum bending moment. Isolated Rectangular footing is provided for the Foundation. Doglegged staircase is provided for emergency exit. The plot area is 21,920 sq.m the building consists of (G+2) floors with a Basement for Car Parking. For simplicity of the design, the loads of doors and windows are neglected. The site is located in Seismic Zone III and the soil is of type III : medium soil. This Project comprised of Planning, Structural Analysis and Design of “SHOPPING COMPLEX” (G+2) in Chennai. Good ventilation, Lighting is given special importance to satisfy the various function requirements. A Good front elevation was also giving to enhance appearance of building. The proposed building was planned to make comfortable aesthetic, economical, good orientation and to meet all requirements. The project is analysed by using moment distribution method. The structure is designed by using limit state method as per IS 456:2000 & SP 16. It is considered as live load and dead load referred as per IS 875:1987- Part - 1 & Part – 2. The detail drawing is drawn by using AutoCAD software. At the end of the project, we are able to analyse and design any type of RC structures in professional practice. 1 LIST OF SYMBOLS A Ac Ag Ast B BV D DL D fck fy LL lx ly Mf Mu Mulim Pu Vu Sv Mx I rv rc M P R T V W W wd X K K L lef lex ley Area Net area of concrete Gross area of section Area of steel on section Breadth of beam Basic value Overall depth of beam or slab Dead Load Effective depth of beam or slab Characteristic compressive strength of concrete Factored Load Live Load Length of shorter side of slab Length of longer side of slab Modification Factor Factored moment Moment of resistance of limiting section Axial Load Factored shear force Spacing of stirrups Bending moment of co-efficient for shorter span Bending moment of co-efficient for longer span Moment per unit width along shorter span Unsupported length of column Nominal shear stress Shear stress in concrete Bending moment Axial load on a compression member Radius Torsional moment Shear force Total load Distributed load per unit area Distributed Dead load per unit area Depth of neutral axis Diameter of bar Stiffness of member Constant or co-efficient or factor Length of a column or beam Effective span of beam or slab or column Effective length about x-x axis Effective length about y-y axis 2 INTRODUCTION Construction of shopping complex are useful in saving the land as many types of shops can be included in a single building. Moreover, we can get all the required things in a place. In our project we have provided different shops for clothing, household appliances, electrical items, furniture, toys & stationery items, shoes, ice cream shop, saloon, sports store, service centre pets shops pharmacies, restaurants, theatres, etc. The planning of this project is done keeping in view all the requirements for a better assembling of people. The analysis for all elements of the building is done as per IS code of practice for Plain and Reinforced cement concrete IS456-2000 and SP-16 design aids for designing the elements. 3 ANALYSIS 4 ANALYSIS OF A COMPONENT ( BEAM ) Required Data’s : Size of a beam - - - B = 300 mm ; D = 650 mm Factored load on beam = 29.34 kn/m E = 5000 x √fck = 29580.40 mm2 I = ( b d3 ) / 12 = 68.66 x 108 mm4 [ 300 x 650 mm ] STEP – 1 : ( Calculate F.E.M ) SPAN NUMBER SPAN LENGTH (m) UDL ( kn/m ) L1 8 29.34 L2 8 29.34 L3 8 29.34 L4 8 29.34 Fixed End Moments ( kn.m ) Mf AB -156.48 Mf BA 156.48 Mf BC -156.48 Mf CB 156.48 Mf CD -156.48 Mf DC 156.48 Mf DE -156.48 Mf ED 156.48 STEP – 2: ( Calculate D.F ) Joint Member Stiffness ( K ) BA 2.54 x 1013 BC 2.54 x 1013 CB 2.54 x 1013 CD 2.54 x 1013 DC 2.54 x 1013 DE 2.54 x 1013 B C D Total Stiffness ( ∑ K ) AB I 68.66 x 108 BA 68.66 x 108 0.5 5.08 x 1013 0.5 0.5 5.08 x 1013 0.5 0.5 5.08 x 1013 STEP – 3 : ( Calculate Distribution of moment ) JOINT A B MEMBER Distribution Factor ( D.F = K / ∑K ) BC 68.66 x 108 CB 68.66 x 108 5 0.5 C D CD 68.66 x 108 DC 68.66 x 108 E DE 68.66 x 108 ED 68.66 x 108 L 8 8 8 8 8 8 8 8 K 2.54 x 1013 2.54 x 1013 2.54 x 1013 2.54 x 1013 2.54 x 1013 2.54 x 1013 2.54 x 1013 2.54 x 1013 D.F 0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 F.E.M -156.48 156.48 -156.48 156.48 -156.48 156.48 -156.48 156.48 BALANCE - 0 0 0 0 0 0 - STEP – 4 : ( Analysis Diagram ) CONTINUOUS BEAM --- REACTIONS & END MOMENT 6 SHEAR FORCE DIAGRAM BENDING MOMENT DIAGRAM SLOPE DIAGRAM 7 DESIGN 8 FLAT SLAB DESIGN [ TERRACE ] REQUIRED DATAS : Panel Size = 8 m x 8 m Column Size = 0.6 m x 0.6 m Height = 4.5 m Live Load = 2.5 kn/m2 Super Imposed Dead Load = 2.8 kn/m2 fck = 25 n/mm2 & fy = 500 n/mm2 A] INTERIOR PANEL – STEP – 1 : ( Thickness of Slab ) Span / effective depth = 40 x 0.8 8000/d = 32 d = 8000/32 = 250 mm > 125 mm [ minimum thickness of slab ] assuming 12 mm and clear cover = 20 mm Overall Depth, D = d + /2 + clear cover = 250 + (12/2) + 20 = 276 mm Adopt a Overall Depth of D = 280 mm Effective depth, d = 254 mm STEP – 2 : ( Size of Drop Panel ) Drop Panel size should not be less than = 8000/3 = 2666.67 mm Minimum depth of Drop Panel = 1/4th of D = ( 1/4 ) x 280 = 70 mm Depth of Slab including Drop Panel = 280 + 70 = 350 mm Width of Column strip = Width of middle strip = 8000/2 = 4000 mm Drop Panel Size = 4000 mm x 4000 mm STEP – 3 : ( Load Calculations ) Live Load = 2.5 kn/m2 Super Imposed Dead Load = 2.8 kn/m2 [ finishes ] Dead Load of Slab = 0.28 x 25 = 7 kn/m2 Dead Load of Drop Panel = 0.07 x 25 = 1.75 kn/m2 Total Characteristics Load, WC = 2.5 + 2.8 + 7 + 1.75 = 14.05 kn/m2 Factored Load, Wf = 14.05 x 1.5 = 21.08 kn/m2 L1 & L2 = c/c span = 8 m ; Ln = 8 – ( 0.6 / 2 ) – ( 0.6 / 2 ) = 7.4 m Design Load, Wn = Wf x Ln x L2 = 21.08 x 7.4 x 8 = 1247.94 kn STEP – 4 : ( Bending Moment Calculation ) 9 Mo = ( Wn . Ln ) / 8 = (1247.94 x 7.4) / 8 = 1154.34 kn.m 1155 kn.m As per IS 456 : 2000, Clause – 31.4.3.2 -ve design moment = 0.65 x Mo = 0.65 x 1155 = 750.75 kn.m +ve design moment = 0.35 x Mo = 0.35 x 1155 = 404.25 kn.m As per IS 456 : 2000, Clause – 31.5.5.1 & 31.5.5.3 TYPE COLUMN STRIP ( kn.m ) MIDDLE STRIP ( kn.m ) - ve moment 750.75 x 0.75 = 563.06 750.75 – 563.06 = 187.69 + ve moment 404.25 x 0.60 = 242.55 404.25 – 242.55 = 161.70 STEP – 5 : ( Check for effective depth, d ) dreq. (slab) = √ (Mu / 0.138 x fck x b ) = √ [ ( 691.28 x 106 ) / ( 0.138 x 25 x 4000 ) ] = 223.81 mm < 254 mm dprov. (drop panel) = 254 + 70 = 324 mm < 350 mm Hence, it’s safe.. dreq. < dprov. STEP – 6 : ( Main Reinforcement calculation ) BM = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 1. COLUMN STRIP : [ -ve reinforcement ] 563.06 x 106 = 0.87 x 500 x Ast x 324 x [ 1 – ( 500 x Ast ) / ( 25 x 4000 x 324 ) ] Ast = 3917.5 mm2 Assuming 12 mm, ast = 113.10 mm2 Spacing, Sv = ( 4000 x ast ) / Ast = ( 4000 x 113.10 ) / ( 3917.5 ) = 110 mm c/c [ +ve reinforcement ] : Ast = 1631.11 mm2 Sv = 260 mm c/c 2. MIDDLE STRIP : [ -ve reinforcement ] 187.69 x 106 = 0.87 x 500 x Ast x 254 x [ 1 – ( 500 x Ast ) / ( 25 x 4000 x 254 ) ] Ast = 1759.66 mm2 Sv = 250 mm c/c 10 [ +ve reinforcement ] : Ast = 1508.26 mm2 Sv = 280 mm c/c STEP – 7 : ( Check for punching shear ) d/2 distance from column 600/2 = 300 mm Perimeter of critical section = bo = 4 ( a + d ) = 4 ( 600 + 300 ) = 3600 mm Shear Force on this plane, Vu = W [ L x L – ( a + d ) ( a + d ) ] = 14.05 [ 82 – 0.81 ] = 887.82 kn Nominal Shear stress = ( Vu / b . d ) = (887.82 x 103 ) / ( 4000 x 350 ) = 0.63 n/mm2 ks = ( 0.5 + ßc ) = 0.5 + 1 = 1.5 but not greater than 1. ßc = 0.6/0.6 = 1 [ Ratio of short side to long side of the column ] τc = 0.25 √fck = 0.25 x √25 = 1.25 n/mm2 ks . τc = 1 x 1.25 = 1.25 n/mm2 ... The actual shear stress of 0.63 n/mm2 is within safe permissible limits. STEP – 8 : ( Integrity Reinforcement ) As = ( 0.5 . wf . L1 . L2 ) / ( 0.87 . fy ) = [ ( 0.5 . 21.08 . 8 . 8 ) / ( 0.87 . 500 ) x 103 ] = 1550.71 mm2 Provide two 25 mm diameter bars, with a length of 2.Ld = ( 2 x 1071.43 ) = 2142.86 mm2 passing through the column cage each way. FLAT SLAB DESIGN [ FLOORS ] REQUIRED DATAS : Panel Size = 8 m x 8 m Column Size = 0.6 m x 0.6 m Height = 4.5 m Live Load = 6 kn/m2 Super Imposed Dead Load = 2.5 kn/m2 fck = 25 n/mm2 & fy = 500 n/mm2 Note : Live Loads taken from IS 875 : 1987 ( PART – II ) As per IS 456 : 2000 A] INTERIOR PANEL – STEP – 1 : ( Thickness of Slab ) Span / effective depth = 40 x 0.8 8000/d = 32 d = 8000/32 = 250 mm > 125 mm [ minimum thickness of slab ] 11 assuming 12 mm and clear cover = 20 mm Overall Depth, D = d + /2 + clear cover = 250 + (12/2) + 20 = 276 mm Adopt a Overall Depth of D = 280 mm Effective depth, d = 254 mm STEP – 2 : ( Size of Drop Panel ) Drop Panel size should not be less than = 8000/3 = 2666.67 mm Minimum depth of Drop Panel = 1/4th of D = ( 1/4 ) x 280 = 70 mm Depth of Slab including Drop Panel = 280 + 70 = 350 mm Width of Column strip = Width of middle strip = 8000/2 = 4000 mm Drop Panel Size = 4000 mm x 4000 mm STEP – 3 : ( Load Calculations ) Live Load = 6 kn/m2 Super Imposed Dead Load = 2.5 kn/m2 [ finishes ] Dead Load of Slab = 0.28 x 25 = 7 kn/m2 Dead Load of Drop Panel = 0.07 x 25 = 1.75 kn/m2 Total Characteristics Load, WC = 6 + 2.5 + 7 + 1.75 = 17.25 kn/m2 Factored Load, Wf = 17.25 x 1.5 = 25.88 kn/m2 L1 & L2 = c/c span = 8 m ; Ln = 8 – (0.6/2) – (0.6/2) = 7.4 m Design Load, Wn = Wf x Ln x L2 = 25.88 x 7.4 x 8 = 1532.10 kn STEP – 4 : ( Bending Moment Calculation ) Mo = ( Wn . Ln ) / 8 = (1532.10 x 7.4) / 8 = 1417.19 kn.m 1418 kn.m As per IS 456 : 2000, Clause – 31.4.3.2 -ve design moment = 0.65 x Mo = 0.65 x 1418 = 921.70 kn.m +ve design moment = 0.35 x Mo = 0.35 x 1418 = 496.30 kn.m As per IS 456 : 2000, Clause – 31.5.5.1 & 31.5.5.3 TYPE COLUMN STRIP ( kn.m ) MIDDLE STRIP ( kn.m ) - ve moment 921.70 x 0.75 = 691.28 921.70 – 691.28 = 230.42 + ve moment 496.30 x 0.60 = 297.78 12 496.30 – 297.78 = 198.52 STEP – 5 : ( Check for effective depth, d ) dreq. (slab) = √ (Mu / 0.138 x fck x b ) = √ [ ( 691.28 x 106 ) / ( 0.138 x 25 x 4000 ) ] = 223.81 mm < 254 mm dprov. (drop panel) = 254 + 70 = 324 mm < 350 mm Hence, it’s safe.. dreq. < dprov. STEP – 6 : ( Main Reinforcement calculation ) BM = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 1. COLUMN STRIP : [ -ve reinforcement ] 691.28 x 106 = 0.87 x 500 x Ast x 350 x [ 1 – ( 500 x Ast ) / ( 25 x 4000 x 350 ) ] Ast = 4880.74 mm2 Assuming 12 mm, ast = 113.10 mm2 Spacing, Sv = ( 4000 x ast ) / Ast = ( 4000 x 113.10 ) / ( 4880.74 ) = 90 mm c/c [ +ve reinforcement ] : Ast = 2013.80 mm2 Sv = 220 mm c/c 2. MIDDLE STRIP : [ -ve reinforcement ] 230.42 x 106 = 0.87 x 500 x Ast x 324 x [ 1 – ( 500 x Ast ) / ( 25 x 4000 x 324 ) ] Ast = 2178.89 mm2 Sv = 200 mm c/c [ +ve reinforcement ] : Ast = 1440.57 mm2 Sv = 300 mm c/c STEP – 7 : ( Check for punching shear ) d/2 distance from column 600/2 = 300 mm Perimeter of critical section = bo = 4 ( a + d ) = 4 ( 600 + 300 ) = 3600 mm Shear Force on this plane, Vu = W [ L x L – ( a + d ) ( a + d ) ] = 15.5 [ 82 – 0.81 ] = 979.45 kn Nominal Shear stress = ( Vu / b . d ) = (979.45 x 103 ) / ( 4000 x 350 ) = 0.70 n/mm2 ks = ( 0.5 + ßc ) = 0.5 + 1 = 1.5 but not greater than 1. ßc = 0.6/0.6 = 1 [ Ratio of short side to long side of the column ] τc = 0.25 √fck = 0.25 x √25 = 1.25 n/mm2 ks . τc = 1 x 1.25 = 1.25 n/mm2 ... The actual shear stress of 0.70 n/mm2 is within safe permissible limits. 13 STEP – 8 : ( Integrity Reinforcement ) As = ( 0.5 . wf . L1 . L2 ) / ( 0.87 . fy ) = [ ( 0.5 . 25.88 . 8 . 8 ) / ( 0.87 . 500 ) x 103 ] = 1903.82 mm2 Provide two 25 mm diameter bars, with a length of 2.Ld = ( 2 x 1071.43 ) = 2142.86 mm2 passing through the column cage each way. COLUMN STRIP = DROP WIDTH COLUMN STRIP = DROP WIDTH MIDDLE STRIP 4000 COLUMN STRIP = DROP WIDTH # 12 - 110 c/c 4000 MIDDLE STRIP # 12 - 260 c/c # 12 - 250 c/c 4000 COLUMN STRIP = DROP WIDTH # 12 - 280 c/c 8000 BOTTOM BARS TOP BARS REINFORCEMENT DETAILS OF FLAT SLAB 260 # 12 - 110 c/c # 12 - 260 c/c 800 REINFORCEMENT DETAILS OF COLUMN STRIP 350 # 12 - 110 c/c # 12 - 260 c/c 800 REINFORCEMENT DETAILS OF MIDDLE STRIP 14 TWO WAY SLAB [ AHU Room, Electric room, others, etc., ] REQUIRED DATAS : Lx = 5 m Ly = 6 m fck = 25 n/mm2 fy = 500 n/mm2 ( ly / lx ) = ( 6 / 5 ) = 1.2 --- Two way slab simply supported on all sides with provision for torsion at corners. STEP – 1 : ( Depth of Slab ) As the span is more than 3.5 m, adopt a span/depth ratio of 25. Effective depth, d = Span / 25 = 5000 / 25 = 200 mm assuming 12 mm and clear cover = 20 mm Overall Depth, D = d + /2 + clear cover = 200 + (12/2) + 20 = 226 mm Adopt a Overall Depth of D = 230 mm Effective depth, d = 204 mm STEP – 2 : ( Effective Span ) Effective span = Clear span + effective depth = 5 + 0.204 = 5.204 m STEP – 3 : ( Loads ) Dead Load = 0.2 x 25 = 5 kn/m2 Live Load = 2.5 kn/m2 Super Imposed Dead Load = 1 kn/m2 [ finishes ] Considering 1 m width, Total Characteristic Loads = 8.5 kn/m Factored Load = 8.5 x 1.5 = 12.75 kn/m STEP – 4 : ( Ultimate Design moments and shear forces ) From IS 456 : 2000, Table 27 – co-efficients αx = 0.084 ; αy = 0.059 Mx = αx . w. lx2 = 0.084 x 12.75 x 5.2042 = 29 kn.m My = αy . w. lx2 = 0.059 x 12.75 x 5.2042 = 20.37 kn.m Vux = 0.5 . w . lx = 0.5 x 12.75 x 5.204 = 33.18 kn STEP – 5 : ( Check for effective depth, d ) Mmax = 0.138 fck b d2 d = √ [ ( 29 x 106 ) / ( 0.138 x 25 x 1000 ) ] = 91.68 mm < 204 mm 15 Hence, the effective depth selected is sufficient to resist the design ultimate moment. STEP – 6 : ( Reinforcements along Short & Long span direction ) Astmin = (0.12/100) x b x D = (0.12/100) x 1000 x 230 = 276 mm2 BM = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 29 x 106 = 0.87 x 500 x Ast x 204 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 204 ) ] Ast = 338 mm2 Spacing, Sv = ( 1000 x ast ) / Ast = ( 1000 x 113.10 ) / ( 338 ) = 300 mm c/c Adopt 12 mm diameter bars at 300 mmc/c in shorter span direction. Effective depth, d = 204 - 12 = 192 mm 20.37 x 106 = 0.87 x 500 x Ast x 192 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 192 ) ] Ast = 250.43 mm2 Spacing, Sv = ( 1000 x ast ) / Ast = ( 1000 x 113.10 ) / ( 250.43 ) = 300 mm c/c Hence, provide 12 mm diameter bars at 300 mm c/c in the long span direction. STEP – 7 : ( Check for Shear stress ) Considering the short span lx and unit width of slab, the shear stress is given by., τv = Vu / b.d = 33.18 x 103 / ( 1000 x 204 ) = 0.16 n/mm2 pt = ( 100 x Ast ) / ( b . d ) = ( 100 x 338 ) / ( 1000 x 204 ) = 0.17 % k . τc = 1.12 x 0.304 = 0.34 n/mm2 > 0.16 n/mm2 ( τv ) Hence, the slab is safe against shear. STEP – 8 : ( Check for Deflection ) ( L / d ) basic = 20 x Modification Factor FS = 0.58 . fy . ( Ast req. / Ast prov. ) FS = 0.58 . 500 . ( 338 / 452.39 ) = 216.67 n/mm2 M F = 1.8 ( L / d )max = 20 x 1.8 = 36 ( L / d )provided = 5204 / 204 = 25.51 < 36 Hence, deflection control is satisfied. STEP – 9 : ( Torsion Reinforcements at corners ) Area of reinforcements in each of the four layers = 0.75 x 338 = 253.5 mm2 Distance over which torsion reinforcement is provided = ( L / 5 ) x short span = ( L / 5 ) x 5000 = 1000 mm Provide 8 mm diameter bars at 150 mm c/c for a length of 1000 mm at all four corners in 4 layers. 16 MIDDLE STRIP 4500 EDGE STRIP EDGE STRIP 600 600 # 8 - 150 c/c EDGE STRIP 625 0.10 Ly = 600 X EDGE STRIP 625 Ly = 6 m MIDDLE STRIP 3750 X TORSION REINFORCEMENT Lx = 5 m # 12 - 300 c/c 230 # 12 - 300 c/c 5000 SECTION X X REINFORCEMENT DETAILS IN TWO WAY SLAB ( with provision for torsion at corners ) EDGE BEAM REQUIRED DATAS : fck = 25 n/mm2 fy = 500 n/mm2 Clear Span = 8 m Bearing wall thickness = 300 mm STEP – 1 : ( Cross sectional Dimensions ) Assuming effective depth = ( Span / 15 ) = [ ( 8 x 103 ) / 15 ] = 533.33 mm Adopt d = 600 mm, D = 650 mm, b = 300 mm Cover to tension steel = 50 mm STEP – 2 : ( Loads ) Live Load, q = 6 kn/m Self weight of beam = 0.65 x 0.3 x 25 = 4.88 kn/m Total Dead Load, g = 3.8 + 4.88 = 8.68 kn/m 17 Total characteristics load = 19.56 kn/m STEP – 3 : ( Bending moments and Shear forces ) Negative B.M. at interior support is computed as, Mu (-ve) = 1.5 [ gL2/10 + qL2/9 ] = 1.5 [ ( 8.68 x 82 ) / 10 + ( 6 x 82 ) / 9 ] = 147.33 kn.m Positive B.M. at centre of span is computed as, Mu (+ve) = 1.5 [ gL2/12 + qL2/10 ] = 1.5 [ ( 8.68 x 82 ) / 12 + ( 6 x 82 ) / 10 ] = 127.04 kn.m Maximum shear force at the support section is given by, Vu = 0.6 L ( g + q ) 1.5 = ( 0.6 x 8 ) ( 6 + 8.68 ) 1.5 = 105.70 kn.m STEP – 4 : ( Limiting moment of resistance ) Mu,lim = 0.138 fck b d2 = [ 0.138 x 25 x 300 x 6002 ] x 10-6 = 372.6 kn.m Since Mu < Mu,lim, the section is under reinforced. STEP – 5 : ( Main Reinforcements ) Mu (-ve) = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 147.33 x 106 = 0.87 x 500 x Ast x 600 x [ 1 – ( 500 x Ast ) / ( 25 x 300 x 600 ) ] Ast = 605.18 mm2 Using 2 bars of 20 mm diameter on the tension side (Ast = 628.32 mm2)at supports. Mu (+ve) = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 127.04 x 106 = 0.87 x 500 x Ast x 600 x [ 1 – ( 500 x Ast ) / ( 25 x 300 x 600 ) ] Ast = 516.37 mm2 Using 2 bars of 20 mm diameter on the tension face (Ast = 628.32 mm2) at midspan. STEP – 6 : ( Shear Reinforcements ) τv = Vu / b.d = 105.70 x 103 / ( 300 x 600 ) = 0.59 n/mm2 pt = ( 100 x Ast ) / ( b . d ) = ( 100 x 628.32 ) / ( 300 x 600 ) = 0.35 % τc = 0.412 n/mm2 < 0.59 n/mm2 ( τv ) Since τv > τc , shear reinforcements are to be designed to resist the balance shear computed as Vus = [ 105.70 – ( 0.412 x 300 x 600 ) 10-3 ] = 31.65 kn Sv = [ 0.87 fy Asv d / Vus ] = [ 0.87 x 500 x 2 x 50.27 x 600 / 31.65 x 103 ] = 829.10 mm Using 8 mm diameter 2 legged stirrups at 300 mm centres throughout the beam. 18 Y X Y X # 8 - 300 c/c 650 2 - # 25 2 - # 20 6000 6000 650 2 - # 25 2 - # 20 300 SECTION - XX SECTION - YY REINFORCEMENT DETAILS IN CONTINUOUS BEAM AXIALLY LOADED COLUMN REQUIRED DATAS : Number of story = Basement + G + 2 ( 3 STORY ) Height of floor = 4.675 m Size of column = 600 mm x 600 mm External and Internal wall thickness = 300 mm both fck = 25 n/mm2 & fy = 500 n/mm2 SBC = 200 kn/m2 I. INTERIOR COLUMN : Load Calculations -1. Factored Load on Roof Slab = 21.08 kn/m2 2. Factored Load on Floor Slab = 15.05 kn/m2 3. Factored Load of Wall = 34.88 kn/m Floor Area surrounded by column = 8 x 8 = 64 m2 Roof to 2nd Floor – Roof Load = 21.08 x 8 x 8 = 1349.12 kn Walls Load = 34.88 x 4.075 x 0.15 = 21.32 kn Total Load = 1370.44 kn 2nd Floor to 1st Floor – Floor Load = 15.05 x 8 x 8 = 963.20 kn Walls Load = 34.88 x 4.075 x 0.15 = 21.32 kn Load from Top Floor = 1370.44 kn Cummulative Load = 2354.96 kn 1st Floor to Plinth – 19 Floor Load = 15.05 x 8 x 8 = 963.20 kn Walls Load = 34.88 x 4.075 x 0.15 = 21.32 kn Load from Top Floor = 2354.96 kn Cummulative Load = 3339.48 kn II Floor – STEP – 1 : ( Slenderness Ratio ) L / D = 4675 / 600 = 7.79 < 12 Hence, the column is designed as a Short Column. nd STEP – 2 : ( Minimum Eccentricity ) emin = [ L / 500 + D / 30 ] = [ ( 4675 / 500 ) + ( 600 / 30 ) ] = 29.35 > 20 mm 0.05 D = 0.05 x 600 = 30 mm STEP – 3 : ( Longitudinal Reinforcements ) Pu = [ 0.4 . fck . Ag + ( 0.67 . fy + 0.4 . fck ) Asc ] 1370.44 x 103 = ( 0.4 . 25 . 600 . 600 ) + ( 0.67 . 500 + 0.4 . 25 ) Asc Asc = 5568.87 mm2 Assume 25 mm & 20 mm diameter bars Provide 7 nos. of 25 mm dia bars, Asc = 3436.12 mm2 Provide 7 nos. of 20 mm dia bars, Asc = 2199.11 mm2 Total Asc = 5635.23 mm2 > 5568.87 mm2 Minimum Asc = 0.8 % of B . D = 0.8/100 x 600 x 600 = 2880 mm2 Maximum Asc = 6 % of B . D = 6/100 x 600 x 600 = 21600 mm2 STEP – 4 : ( Lateral Ties ) I. ( 1 / 4 ) x 25 = 6.25 mm II. 6 mm STEP – 5 : ( Spacing ) I. Least Lateral Dimensions = 600 mm II. 16 x D =16 x 25 = 400 mm III. 300 mm Provide 8 mm diameter ties at 300 mm c/c. 20 520 600 4 - # 25 mm 4 - # 20 mm TIES - # 8 - 300 c/c REINFORCEMENT DETAILS UNIAXIAL ECCENTRIC LOADED COLUMN REQUIRED DATAS : Size of column = 600 mm x 650 mm fck = 25 n/mm2 & fy = 500 n/mm2 Ultimate Load, Pu = 1370.44 kn Ultimate moment, Mu = 200 kn.m STEP – 1 : ( Non-Dimensional Parameters ) ( Pu / fck b D ) = 0.14 ( Mu / fck b D2 ) = 0.03 STEP – 2 : ( Longitudinal Reinforcements ) Adopting an effective cover of 50 mm = d / ( d / / D ) = 0.10 Refer chart 33 of SP : 16 and read out the ratio ( p /fck ) = 0.02 P = 25 x 0.02 = 0.50 Asc = ( p b D / 100 ) = 1950 mm2 Adopt 5 bars of 25 mm dia. Area provided = 2454.37 mm2 Provide 5 bars on each of the short faces at an effective cover of 50 mm. STEP – : 3 ( Lateral ties ) I. ( 1 / 4 ) x 25 = 6.25 mm II. 6 mm STEP – 4 : ( Spacing ) I. Least Lateral Dimensions = 600 mm II. 16 x D =16 x 25 = 400 mm III. 300 mm 21 Provide 8 mm diameter ties at 300 mm c/c. 650 600 8 - # 25 mm # 8 mm TIES @ 300 mm c/c REINFORCEMENTS IN COLUMNS WITH UNIAXIAL BENDING BIAXIAL ECCENTRIC LOADED COLUMN REQUIRED DATAS : Size of column = 600 mm x 600 mm fck = 25 n/mm2 & fy = 500 n/mm2 Ultimate Load, Pu = 1370.44 kn Ultimate moment, Mu = 120 kn.m @ Major Axis Ultimate moment, Mu = 90 kn.m @ Minor Axis STEP – 1 : ( Equivalent Moment ) The reinforcement in section is designed for the axial compressive load Pu and the equivalent moment given by the relation, Mu = 1.15 √ ( M2ux + M2uy ) = 172.5 kn.m STEP – 2 : ( Non-Dimensional Parameters ) ( Pu / fck b D ) = 0.15 ( Mu / fck b D2 ) = 0.03 STEP – 3 : ( Longitudinal Reinforcements ) Adopting an effective cover of 50 mm = d / ( d / / D ) = 0.10 Refer chart 33 of SP : 16 and read out the ratio ( p / fck ) = 0.06 P = 25 x 0.04 = 1 Asc = ( p b D / 100 ) = 3600 mm2 22 Adopt 8 bars of 25 mm dia. Area provided = 3926.99 mm2 Provide 8 bars of 25 mm dia with 3 bars in each face. P = ( 100 x 3926.99 ) / ( 600 x 600 ) = 1.09 and the ratio ( p / fck ) = 0.04 ( Mux1 / fck b D2 ) = 0.04 Mux1 = 0.04 x 25 x 600 x 6002 = 235.44 kn.m Due to symmetry, Mux1 = Muy1 = 235.44 kn.m Pu = [ 0.45 fck Ac + 0.75 fy As ] = 5478.44 kn Pu / Puz = 0.25 STEP – : 4 ( Check for safety under Biaxial Loading ) ( Mux / Mux1 )αn + ( Muy / Muy1 ) αn < 1 0.51 + 0.38 = 0.89 < 1 Hence, the section is safe under specified loading. STEP – : 5 ( Lateral ties ) III. ( 1 / 4 ) x 25 = 6.25 mm IV. 6 mm STEP – 6 : ( Spacing ) IV. Least Lateral Dimensions = 600 mm V. 16 x D =16 x 25 = 400 mm VI. 300 mm Provide 8 mm diameter ties at 300 mm c/c. 600 600 8 - # 25 mm # 8 mm TIES @ 300 mm c/c REINFORCEMENTS IN COLUMNS WITH BIAXIAL BENDING CIRCULAR COLUMN REQUIRED DATAS : Diameter of column, D = 600 mm Unsupported Length, L = 4675 mm fck = 25 n/mm2 ; fy = 500 n/mm2 23 STEP – 1 : ( Slenderness Ratio ) L / D = 4675 / 600 = 7.79 < 12 Hence, the column is designed as a Short Column. STEP – 2 : ( Minimum Eccentricity ) emin = [ L / 500 + D / 30 ] = [ ( 4675 / 500 ) + ( 600 / 30 ) ] = 29.35 > 20 mm 0.05 D = 0.05 x 600 = 30 mm STEP – 3 : ( Longitudinal Reinforcements ) Pu = [ 0.4 . fck . Ag + ( 0.67 . fy + 0.4 . fck ) Asc ] 1370.44 x 103 = ( 0.4 . 25 . 600 . 600 ) + ( 0.67 . 500 + 0.4 . 25 ) Asc Asc = 5568.87 mm2 Minimum Asc = 0.8 % of B . D = 0.8/100 x 600 x 600 = 2880 mm2 Maximum Asc = 6 % of B . D = 6/100 x 600 x 600 = 21600 mm2 STEP – 4 : ( Helical Reinforcement spirals ) Assuming clear cover of 40 mm over spirals Core diameter = [ 600 – ( 2 x 40 ) ] = 520 mm Area of core = Ac = 206736.43 mm2 Volume of core/m = Vc = 206736.43 x 103 mm3 Gross area of section = Ag = 282743.34 mm2 Using 8 mm diameter helical spirals at a pitch ‘p’ mm, the volume of helical spiral per metre length is given by Vns = (80859 x 103) / p mm3 / m ( Vns / Vc ) < 0.36 [ Ag /Ac ) – 1 ] ( fck / fy ) Solving pitch, p = 58.93 mm p < 75 mm or ( core diameter / 6 ) = 86.67 mm p > 25 mm or ( 3 x diameter of helix ) = 24 mm Hence, provide 10 mm diameter spirals at a pitch of 86 mm. 24 600 86 # 10 - spiral @ pitch 36 mm 12 - # 25 CLEAR COVER 40 mm # 10 - spiral @ pitch 36 mm REINFORCEMENTS IN HELICALLY REINFORCED COLUMN DOG LEGGED STAIRCASE [ Emergency Exit ] REQUIRED DATAS : No. of steps = 10 Tread = 250 mm ; Rise 150 mm UDL = 4 kn/m2 Weight of finishes = 1 kn/m2 STEP – 1 : ( Effective Span ) The landing slabs span parallel with the risers ( perpendicular to the flight direction ) Effective span of flight slab = 2.5 + 1 = 3.5 m STEP – 2 : ( Loads ) Consider 1 m of width of flight slab. Live Load = 4 kn/m Self weight of steps = 1.5 kn/m Assume the total thickness of waist slab as 3.5 x 47 =164.5 165 mm Self weight of slab per m2 of inclined area = 1 x 0.165 x 25 = 4.13 kn/m Self weight of slab per m of horizontal length = 4.82 kn/m Weight of finishes = 1 kn/m Total Characteristics load = 15.45 kn/m Design Load = 23.18 kn/m The same Loading is assumed in the landing portions also. 25 STEP – 3 : ( Bending moments and shearing force ) Design B.M @ midspan = 35.49 kn.m Design S.F @ support = 40.57 kn STEP – 4 : ( Depth required ) For balanced sections of M25 grade concrete and Fe500 grade steel, Moment of resistance = 2.66 b d2 Effective depth required = 115.51 Providing 10 mm dia. Bars with a nominal cover of 20 mm, Effective depth provided = 165 – 20 – 5 = 140 mm > 115.51 mm STEP – 5 : ( Reinforcements ) BM = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 23.18 x 106 = 0.87 x 500 x Ast x 140 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 140 ) ] Ast = 403.93 mm2 Anchorage Length required is, Ld = ( 0.87 x 500 x 8 ) / ( 4 x 1.4 x 1.6 ) = 388.39 mm In addition to Ld, we have to provide sufficient balancing moment to prevent overturning. Distribution reinforcement = 0.12% of b.D = 198 mm2 Spacing, Sv = ( 1000 x ast ) / Ast = ( 1000 x 50.27 ) / ( 198 ) = 253.89 mm 240 mm Provide 8 mm dia. bars at 240 mm c/c STEP – 6 : ( Check for shear & stiffness ) Nominal shear stress = 0.25 n/mm2 Minimum value of permissible shear stress = 0.28 n/mm2 Hence safe. For stiffness, basic value of L / d ratio = 20 % of tension steel = 0.47 % < 0.72 % Stress in steel, fs = ( 0.58 x 500 x 8 ) / 10 = 232 n/mm2 Modification factor = 1.5 Effective depth required for stiffness = 93.33 mm Effective depth provided = 140 mm > 93.33 mm Since the effective depth provided is more than both the requirements, a lesser value of overall depth may be assumed ( D = 140 mm ) and checked. 26 165 T = 300 400 R = 160 WAIST SLAB # 12 - 240 c/c ( main ) LANDING BEAM 4000 REINFORCEMENT IN STAIRCASE FLIGHT RETAINING WALL / GUIDE WALL REQUIRED DATAS : Height of Embankment above ground level = 4 m Safe Bearing capacity of soil = 200 kn/m2 Density of Earth = 18 kn/m3 Angle of Repose = 30° Co-efficient of friction = 0.5 M 25 & Fe 500 STEP – 1 : ( Dimensions of retaining wall ) Minimum depth of Foundation = ( p / ɣe ) [ (1-sin) / (1-sin) ]2 = 1.23 m ∴ Provide depth of foundation = 1.2 m Overall Depth of wall = 4 + 1.2 = 5.2 m Thickness of base slab = (h/12) = 5200/12 = 433.33 mm Adopt thickness of base slab, tb = 450 mm ∴ Height of stem, hs = 5.2 – 0.45 = 4.75 m Co-efficient of Active earth pressure is computed as, Ca = [ (1-sin) / (1-sin) ] = 0.333 Width of base slab = 0.4 H to 0.7 H = 1.9 m to 3.33 m Adopt B = 3 m Width of heel slab = 0.5 B = 0.5 x 3 = 1.5 m Width of toe slab = 3 – ( 1.5 + 0.45 ) = 1.05 m STEP – 2 : ( Stability computations ) 27 Vertical Load Parts Force (kn) Distance from heel (m) Moment (kn.m) W1 Soil on Heel 128.25 0.75 96.19 W2 Stem ( Triangle ) 38.59 1.63 62.71 W3 Stem ( Rectangle ) 23.75 1.85 43.94 W4 Base Slab 33.75 ∑W = 224.34 1.50 50.63 ∑M = 253.46 Total = STEP – 3 : ( Design of Stem ) Mu = ( 1.5 Ca ɣe h3 ) / 6 = 159.15 kn.m Consider cover = 50 mm Mu = 0.87 x fy x Ast x d x [ 1 – ( fy x Ast ) / ( fck x b x d ) ] 253.46 x 106 = 0.87 x 500 x Ast x 400 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 400 ) ] Ast = 1581.77 mm2 Provide 20 mm dia. bars @ 150 mm c/c. STEP – 4 : ( Calculation of Earth pressure ) Distance of point of application of resultant from edge of heel, Z = ∑M / ∑W = 1.13 Eccentricity, e = [ Z – ( 0.5 x B ) ] = - 0.37 < 0.5 B / 6 = 0.5 Pmax & Pmin = ( W / B ) [ 1 + 6 e / B ] Pmax = 130.12 kn/m2 Pmin = 19.44 kn/m2 STEP – 5 : ( Calculation of Moment ) By interpolating the Pmax & Pmin values with required distance, we get the pressure distribution values below for the heel and toe design. P1 -118.87 kn/m2 P2 -80.13 kn/m2 P3 21.97 kn/m2 P4 77.31 kn/m2 Moment for the design of Heel = 1.5 x (P3 x (1.52 / 2) + [ (P4 - P3) x (1.52) / 3 ] = 37.07 + 41.51 = 78.58 kn.m 28 Moment for the design of Toe = 1.5 x (P2 x (1.052 / 2) + [ (P1 – P2) x (1.052) / 3 ] = 66.26 + 14.24 = 80.50 kn.m STEP – 6 : ( Design of Heel ) 78.58 x 106 = 0.87 x 500 x Ast x 400 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 400 ) ] Ast = 462.30 mm2 Provide 20 mm dia. bars @ 300 mm c/c. STEP – 7 : ( Design of Toe ) 80.50 x 106 = 0.87 x 500 x Ast x 400 x [ 1 – ( 500 x Ast ) / ( 25 x 1000 x 400 ) ] Ast = 473.87 mm2 Provide 20 mm dia. bars @ 300 mm c/c. STEP – 8 : ( Distribution reinforcements ) Ast = 0.12% of b .D 0.12 / 100 x b x D = 432 mm2 Assuming 12 mm dia. bars Spacing, Sv = ( 1000 x ast ) / Ast = 261.8 250 mm Provide 12 mm dia. bars @ 250 mm c/c as distribution reinforcements for Stem, Heel slab & Toe slab. STEP – 9 : ( Check for overturning ) Mo = ( Ca ɣe hs3 ) / 6 = 106.10 kn.m Ms = ∑W ( B – Z ) = 419.52 kn.m F.0.S against overturning = ( 0.9 x Ms ) / Mo = 3.56 > 1.4 Hence it’s safe against overturning. STEP – 10 : ( Check for overturning ) P = 0.5 Ca ɣe h2 = 80.31 kn.m ∑W = 224.34 kn F.0.S against sliding = ( 0.9 x ∑W ) / P = 2.51 > 1.4 Hence it’s safe against sliding. 29 0.2 # 20 - 150 c/c 1.75 4.75 3 # 12 - 250 c/c 0.45 # 20 - 300 c/c # 20 - 300 c/c 1.05 0.45 1.5 REINFORCEMENT DETAILS IN CANTILEVER RETAINING WALL ISOLATED COLUMN FOOTING REQUIRED DATAS : Factored Load = 3600 kn Size of Column = 600 x 600 mm S.B.C of Soil = 200 kn/m2 M 25 & Fe 500 HYSD bars STEP – 1 : ( Size of Footing ) Load on Column = 3600 kn Weight of footing and backfill at 10% = 360 kn Total Load = 3960 kn Area of footing = ( 3960 / 200 ) = 19.8 m2 Size of Footing = L = B = √19.8 = 4.45 m Adopt 4.5 m x 4.5 m square footing. Net soil pressure at ultimate loads with a load factor of 1.5 is given by qu = ( 3600 x 1.5 ) / ( 4.5 x 4.5 ) = 266.67 kn/m2 = 0.27 n/mm2 STEP – 2 : ( One way Shear ) The critical section is at a distance ‘d’ from the column face. Factored shear force, Vu1 = ( 0.27 x 4500 ) ( 1950 – d ) = 1215 ( 1950 – d ) Assuming percentage of reinforcement in footing, pt = 0.25 % τc = 0.36 n/mm2 30 One way shear resistance = Vct = ( 0.36 x 4500 x d ) = ( 1620 d ) N Vu1 < Vct 1215 ( 1950 – d ) < 1620 d d > 835.71 mm STEP – 3 : ( Two way Shear ) Assuming the effective depth of slab, d = 835.71 mm and computing the 2 way shear resistance at a critical section (d/2) from the face of the column, we have the relation, Vu2 = 0.26 [ 45002 – ( 600 + d2 ] = 0.26 [ 45002 – ( 600 + 835.712 ] = 5083257.09 N Two way shear resistance Vc2 is computed as, Vc2 = ks τc [ 4 ( 600 + d ) d ] where ks = 1 & τc = 0.25 = 1.118 n/mm2 Vc2 = 2683.2 d + 4.47 d2 Vu2 < Vct 5083257.09 N < ( 2683.2 d + 4.47 d2 ) Solving, d = 807.69 mm Hence, one way shear is more critical. Adopt effective depth, d = 1712.5 mm and Overall depth, D = 1800 mm STEP – 4 : ( Design of Reinforcements ) Ultimate moment at column face, Mu = 3960 x 1.950 x 0.5 = 3861 kn.m / m ( Mu / bd2 ) = 1.32 Refer table – 2 of SP : 16 and interpolate the percentage reinforcement as, pt = 0.32 % assumed for 1 way-shear. Ast = ( pt x b x d ) / 100 = 5480 mm2 / m Using 25 mm dia bars, Spacing of bars, S = 100 mm c/c Adopt 25 mm dia bars @ 100 mm c/c in both directions. 31 600 COLUMN REINFORCEMENT 1800 # 25 - 100 mm c/c ( BOTH WAYS ) 4500 SECTION X - X SECTION FOR MOMENT SECTION FOR 1 WAY SHEAR X 600 4500 X SECTION FOR 2 WAY SHEAR 600 d/2 d 4500 PLAN DESIGN OF COLUMN FOOTING 32 CONCLUSION ➢ The Shopping Complex is designed for about 21.920 sq. m. ➢ For the safety of the Shopping Complex, we checked out the Bending Moment, Shear force and Deflection control by using Limit State Method. ➢ Thus the Shopping Complex is designed with safe and economical. 33 REFERENCES ➢ MODEL BUILDING BYE – LAWS, 2016 ➢ IS code of practice for Plain and RCC - IS 456-2000 ➢ IS code of practice for design loads - IS 875 (Part 1 – Super imposed Loads) – 1987 ; (Part 2 – Imposed Loads) – 1987 ➢ Design aids for RCC structures (S.P. 16), Bureau of Indian Standards, New Delhi. ➢ Reinforced Concrete Design – AUTHOR – N. Krishna Raju & R.N. Pranesh : New Age International (P) Limited, Publishers 34