CHAPTER-I INTRODUCTION 1.1 General The safe and accurate design of a 10 storied building for a frame structure, largely depends on the size/shape of column for the effect of the lateral load (caused by the wind load and earthquake load), maximum or minimum bending moment for the shape and size of the column, which may help the design criteria of the structure because lateral load does not affect on slab and significantly beam design. 1.2 Objectives of study The objectives of the study are as follows: a) Comparative study of building design with lateral loads and without lateral loads. b) To get introduced with different way used for analyzing superstructure. c) To compare the results (reinforcement) of without considering lateral load and considering lateral loads. 1.3 Scope of works Without lateral load condition column has been design only gravity loads. Beams only for singly design method are used in this study. In this study slab design not required because lateral load does not affect on slab. 1.4 Methodology Keeping a close look to the followings, the project has been accomplished: 1) Analysis of the superstructure. 2) Design of the superstructure without considering lateral load. 3) Analysis of the superstructure by using ETABS. 1 4) Design of the Superstructure considering lateral load. 5) Comparison of the results for both conditions. 1.5 Limitations In this study no dynamic analysis is done for lateral loads. Dynamic analysis for lateral loads would give more accurate and reliable results. If dynamic analysis was performed then this study would have been more safe, economic and aesthetic. 2 CHAPTER-II LITERATURE REVIEW 2.1 General Reinforced Cement Concrete (RCC) has become the best choice to the structural engineers as a design option over the decades around the world. It gives better performance, easy to construct can be given any shape we like. Concrete is weak in tension but good in compression. On the other hand steel is both good in tension and compression. Concrete is good against corrosion but steel is vulnerable against corrosion. Again, concrete has good fire resistance properties but steel is very poor in this case. So, in can be inferred that concrete has some good qualities which steel does not possess and steel has some weakness which concrete can cover. And luckily and interestingly when they are used together in combination they offer us all the properties and qualities we need. In all sorts of structural members there are always tensions and compressions, either on the top or at the bottom, depending on the support conditions and loading conditions. When the members are heavily loaded, on the compression Zone concrete can take a substantial amount of compression up to a certain limit (when limit crosses steel is introduced which is known as doubly reinforced as steel is good in compression too) But on the tension zone concrete can not take tension. Tensile strength of normal weight concrete ranges from 3 to 5√f 'c (10% of √f 'c as a thumb rule). That means a 4000 psi concrete can take only 400 psi in tension. But the tensile stress comes is as high as 60000 psi or more which is well beyond concrete’s ability. This is why steel is introduced in tension zone as a reinforcement to take tension. Steel can take up to 75000 psi or even more in tension. This is why the name RCC comes from. Again, Concrete is alkaline in character. It has a typical PH value ranging 12 to 13. When steel is used in RCC, steel does not get rusted until its PH value goes below 9.0. So steel is better protected in concrete. 3 2.2 Flexural analysis and design of beams Flexural analysis got its theoretical ground when Euler–Bernoulli proposed their beam theory. Apart from this stress- strain analysis, some assumptions when stress becomes non-linear and using of equation of static equilibrium paved the way of today’s Flexural Analysis and Design procedure. The basic assumptions of Flexural Analysis of Beam can be stated as – 1) Euler–Bernoulli beam theory (also known as engineer's beam theory, classical beam theory or just beam theory) is a simplification of the linear theory of elasticity. In the Euler-Bernoulli theory of slender beams, a major assumption is that 'plane sections remain plane before and after bending' where any deformation due to shear across the section is not accounted for. Also, this linear distribution is only applicable if the maximum stress is less than the yield stress of the material. 2) Beam behaves elastically up to proportional limit .Neutral axis passes through the center of gravity of the cross section. Stress at any point in the section can be represented by the equation – f = My / I In the figure below the beam illustrates how plane section remains plane in a beam ρ θ Distorted section of bent beam Bent element from which relation for elastic curve is obtained 4 2.2.1 Conditions of designing tension reinforced rectangular beam In order to ensure that a tension reinforced rectangular beam can resist hypothetical loads. Required strength must be less than or equal to design strength. Design strength can be found by multiplying nominal strength with a strength reduction factor Φ. Therefore – Mu ≤ ΦMn Pu ≤ ΦPn Vu ≤ ΦVn 2.2.2 USD (Ultimate Strength Design) It has been found from experiments and analysis that distribution of internal stress and strain of a beam becomes non –linear near ultimate load. For the first mood of failure, that means steel stress equal yield point, concrete will either fail by crushing of concrete or yielding of steel in the compression zone. The exact behavior of concrete is yet to be known. But it has been possible to measure concrete strain from 0.0030 to 0.004 before failure for a rectangular beam. In order to ensure yielding of steel before crushing of concrete, it is not really necessary to know the exact shape of concrete. The most important thing to know is for a given distance c of the neutral axis 1) total resultant compression force C in the concrete and 2) its vertical location (Location of Resultant Force). In a rectangular beam compressive strength on area bc can be expressed as – C = favbc. In order to express the equation in terms of f'c, a ratio α has been introduced which can be expressed as α = fav / f'c , therefore – C = α f'c bc c γ = αa γ f'c C = α f'c cb C = γ f'c ab When concrete reaches its ultimate load it takes a parabolic stress distribution. This nonlinear stress distribution can be converted to an equivalent rectangular stress distribution of depth a and constant stress γf'c (γ= stress intensity factor). 5 Where, γ = α c/a => αc = γa C = γ f'c ab The value of stress intensity factor γ is 0.85 regardless of f’c . The concrete compression force at failure in a rectangular beam of width b is – C = 0.85 f'c ab From the condition of equilibrium C=T Again, tensile force can be written as – T = Asfs If, failure is initiated by yielding, then fs=fy So, T = Asfy Therefore, 0.85 f'c ab = Asfy => a = Asfy / 0.85 f'c b Substituting, As = ρbd => a = ρbdfy / 0.85 f'c b = ρdfy / 0.85 f'c Nominal moment of an under reinforced beam considering yielding of steel fs = fy at failure Mn = Asfy (d – a/2) Substituting, a = ρdfy / 0.85 f'c Mn = ρbd fy (d – 1/2(ρdfy / 0.85 f'c )) = ρbd2 fy (1 – 0.59ρfy / f'c ) From experimentally obtained values β / α = 0.59, which gives – Mn = ρbd2fy (1 - 0.59 ρfy / f'c ) Mn = Rbd2 R = ρfy (1 - 0.59 ρfy / f'c ) This R is termed as flexural resistant factor. 6 2.3 Moment coefficients Discontinuous end unrestrained: Spandrel: Column: Discontinuous end unrestrained: Spandrel: Column: 0 1 1 11 1 1 1 1 1 1 24 1 14 1 10 11 16 11 11 16 14 1 1 1 11 1 1 1 11 1 24 1 14 1 9 9 14 1 24 1 16 14 14 16 0 0 1 2.4 Column A primarily compression member, which may or may not be designed to carry simultaneous flexural forces, shall be termed a column. 2.4.1 Design of short columns For concentrically axially loaded columns design strength of a column is – Pu =ΦPn = αΦ Ag [0.85f`c + (1 - ρg) + ρg fy] ρg = ratio of area of distributed longitudinal reinforcement to gross concrete area perpendicular to that reinforcement ACI code specifies - 0.01 ≤ ρg ≤ 0.08 But for practice ρg should no go beyond 0.04 for bar splicing and steel congestion. Where: Φ α Tied Columns 0.65 0.80 Spiral Columns 0.70 0.85 7 2.5 ETABS ETABS means Extended 3D Analysis of Building Systems. ETABS is a sophisticated, yet easy to use, special purpose analysis and design program developed specifically for building systems. ETABS Version 9 features an intuitive and powerful graphical interface coupled with unmatched modeling, analytical, and design procedures, all integrated using a common database. Although quick and easy for simple structures, ETABS can also handle the largest and most complex building models, including a wide range of nonlinear behaviors, making it the tool of choice for structural engineers in the building industry. 2.5.1 Overview of ETABS 1. Object-oriented intuitive 2D/3D graphical model generation. 2. Pull down menus, floating tool bars, and tool tip help. 3. Quick data input through property sheets and spreadsheets. 4. Customizable structural templates for creating a model. 5. Full range of analysis including static, concrete. 6. Supports truss and beam members, plates, solids, linear and non-linear cables and curvilinear beams. 7. Flexible zoom, pan and multiple views. 8. Isometric and perspective views 3D shapes. 9. Toggle display of loads, supports, properties, joints, members, etc. 10. Built-in command file editor. 11. Copy &paste through clipboard. 12. Simple command language. 13. State-of-the-art graphical pre and post processors. 14. Rectangular/cylindrical coordinate systems with mix and match capabilities. 15. Joint, member/element, mesh generation with flexible user- controlled numbering scheme. 16. Presentation quality printer plots of geometry and results as part of run output. 17. Performs multiple analysis in the same run - perfect for phase or stage construction. 8 2.5.2 Design Codes 2.5.2.1 Concrete design 1. Design of Concrete Beam, Column per ACI 318. Optional codes include BS8007, BS8110, Canadian, French, German, Spanish, Scandinavian, Japanese, Chinese, Australian, Singaporean and Indian Codes. 2. Numerical and Graphical Design Outputs with reinforcement details. 3. Interactive concrete design and detailing with bar scheduling and interactive rebar layout. 4. Design "physical members" by combining separate beam entities as one with full step-by-step calculation sheets for verification. 2.5.2.2 Analysis and design 1. Plate elements consider inclined supports. 2. Full and partial moment releases (excellent for steel frames where releases defined by springs are hard to determine). 3. Member and spring specification. 4. Fixed, pinned and spring supports with releases. Also Inclined Supports. 5. Automatic spring support generator for mat foundations. 2.5.2.3 Load types and load generation 1. Loading for Joints, Members/Elements including Concentrated, Uniform Linear, Trapezoidal, Temperature, Strain, Support displacement, Pre-stress and Fixed-end Loads. 2. Global, Local and Projected Loading Directions. 3. Uniform or varying Element Pressure Loading on entire or selected portion of plate elements. 4. Floor/Area Load converts load-per-area to member loads based on one-way or two-way actions. 9 2.5.2.4 Model verification 1. 2D/3D drawings on screen as well as on plotter/printer. 2. Graphical representation of the unstable area of a structure due to improper modeling. 3. Full 3D shapes for Beams, Plates and Solids with shading and lighting. 4. Isometric or any rotations for full 3D viewing. Display of Loads, Supports, Orientations, Properties, Hidden line removed, Joint/Member numbering, Dimensions etc. 2.6 Loads for different types of building In designing a floor the following loads are considered: 1. Dead load. 2. Live load. 3. Wind load. 4. Earthquake load 2.6.2 Dead load Dead load is the vertical load due to the weight of permanent structural and non-structural components of building such as walls, floors, ceilings, permanent partitions and fixed service equipment etc. In designing a floor slab, the actual weight of the materials of construction must be added to the live load to obtain the design load. 2.6.2 Live load The live loads are governed by the type of occupancy of the building. Minimum live loads for floors and roofs are given the building regulations of the various cities and the designer is required to make his computations in accordance with the loads specified. In general, live loads are due to human occupancy, furniture, equipment, stored materials, and occasionally movable partitions. 10 2.6.3 Wind load and earthquake load For Buildings having greater height, lateral loads should have to be considered for the design of the building component. Mainly wind loads and Earthquake loads are the major forms of lateral loads. To make the design structurally safe these lateral loads should be considered very cautiously. 2.6.3.1 Wind load Design wind pressure, Pz = CG Cp qz Where, Pz=Design wind pressure at height z, kN/m2 CG=Gust coefficient which shall be Gz or Gh Cp=Pressure coefficient for structures or components qz=Sustained wind pressure =CcCtCzVb2 Ct=Structure importance coefficient Cc=Velocity to pressure conversion coefficient Cz=Combined height and exposure coefficient Vb=Basic wind speed Design wind load for all framing system, F1=ΣPAz Where, F1=Wind force acting normal to a surface P=Design wind pressure on building surfaces Az=Area of the building surface at height z upon which design pressure P operates Design wind load for any building or structure as a whole, F2=ΣPzAz Where, F2=Total wind force on the framed system of the building in a specified direction Pz=Design wind pressure for the cross-sectional shapes of the building Az=Projected frontal area normal to the wind at height z 2.6.3.2 Earthquake load Total design base shear in a given direction, V= ZIC R W Where, Z=Seismic zone coefficient I=Structure importance coefficient R=Response modification coefficient for the structural systems C=Numerical coefficient 1.25π = π 2/3 ≤<2.75 S= Site coefficient for soil characteristics T=fundamental period of vibration of the structure 11 =Ct (hn) ¾ Ct=0.083 (for steel moment resisting frames) =0.073 (for reinforced concrete resisting frames and eccentric braced steel frames) =0.049 (for all other structural systems) hn=Height above the base to level n The vertical distribution of the total lateral force, which is the base shear v, can be given along the height of the structure as: V=Ft+∑ππ=1 Fi Where, Fi=Lateral load applied at story level i Ft=Concentrated lateral force considered at the top of the building in addition to the force Fn =0.07TV ≤ 0.25V (for T > 0.7 second) =0 (for T ≤ 0.7 second) The remaining portion of the base shear (V-Ft) shall be distributed over the height of the building including level n as follows: πΉπ₯ = (V−Ft )Wx hx ∑n i=1 wi hi At each storey level x, the force Fx shall be applied over the area of the building in proportion to the mass distribution at that level. 12 CHAPTER-III BEAM LOAD CALCULATION AND DESIGN WITHOUT LATERAL LOAD Fig. 3.1 Plan 13 Fig. 3.2 Beam area details 14 Fig. 3.3 Grid and beam, column layout 15 3.1 Concrete and steel properties Strength of Concrete f ’c = 4000 psi Yield strength of Steel fy = 60000 psi Unit weight of Concrete = 150 pcf 3.2 Slab thickness calculation Slab thickness "h"= Perimeter/180 = [{2 ∗ (16.75 + 16.50) ∗ 12}/180] = 4.43 in ππππ£ππππ = 5 in 3.3 Load calculation 3.3.1 Dead load calculation:Self weight for slab = 62.5 psf Floor finish = 25 psf False celing = 30 psf Partition wall load = 66.50 psf Total Dead Load = 184 psf πππ‘ππ π·πππ πΏπππ πΉπππ‘ππππ "ππ·πΏ " = 1.2 ∗ D. L psf = 1.2 ∗ 184 psf = 221 psf 3.3.2 Live load calculation:Assume Live Load = 60 psf πππ‘ππ πΏππ£π πΏπππ πΉπππ‘ππππ "WLL " = 1.6 ∗ L. L psf = 1.6 ∗ 60 psf = 96 psf Total Factored Load = (1.2 ∗ D. L + 1.6 ∗ L. L) psf Total Factored Load = (1.2 ∗ 184 + 1.6 ∗ 60) psf πππ‘ππ πΉπππ‘ππππ πΏπππ "π" = 317 psf 16 3.4 Loading area calculation A1 = (7.875)2 = 62 ft 2 2 A2 = (8.75) = 76.56 ft 2 Similarly, A3 = 62 ft 2 A4 = 124 ft 2 A5 = 152.17 ft 2 A6 = 123.97 ft 2 A7 = 75.61 ft 2 A8 = 61.95 ft 2 A9 = 77.77 ft 2 A10 = 58.14 ft 2 A11 = 158.88 ft 2 A12 = 116.28 ft 2 A13 = 156.88 ft 2 A14 = 116.28 ft 2 A15 = 1 15 ∗ (17.75 + 2) ∗ ( ) = 77.77 ft 2 2 2 3.5 Uniformly distributed load calculation for beam Assume Beam size =12"X24" Slab load (factored) = 317 psf Self Weight for Beam Stem (factored) = 12 ∗ 19 ∗ 150 ∗ 1.2 = 285 lb/ft 144 17 Load/ft of Beam WB1 = 62 ∗ 317 + 285 = 1533 lb/ft 15.75 WB2 = 76.56 ∗ 317 + 285 = 1672 lb/ft 17.5 WB3 = 62 ∗ 317 + 285 = 1533 lb/ft 15.75 WB4 = 124 ∗ 317 + 285 = 2781 lb/ft 15.75 WB5 = 152.56 ∗ 317 + 285 = 3041 lb/ft 17.5 WB6 = 123.97 ∗ 317 + 285 = 2780 lb/ft 15.75 WB7 = 75.61 ∗ 317 + 285 = 1655 lb/ft 17.5 WB8 = 61.95 ∗ 317 + 285 = 1532 lb/ft 15.75 WB9 = 77.77 ∗ 317 + 285 = 1674 lb/ft 17.75 WB10 = 58.14 ∗ 317 + 285 = 1494 lb/ft 15.75 WB11 = 156.88 ∗ 317 + 285 = 3087 lb/ft 17.75 WB12 = 116.28 ∗ 317 + 285 = 2702 lb/ft 15.25 WB13 = 156.88 ∗ 317 + 285 = 3087 lb/ft 17.75 WB14 = 116.28 ∗ 317 + 285 = 2702 lb/ft 15.25 WB15 = 77.77 ∗ 317 + 285 = 1674 lb/ft 17.75 18 3.6 Moment calculation 3.6.1 Grid 3 B1 −M = +M = −M = WB1 l2 16 WB1 l2 14 WB1 l2 10 = = = 1533∗15.752 16 1533∗15.752 14 1533∗15.752 10 = 23768 lb-ft = 285 kip-in = 27163 lb-ft = 326 kip-in = 38028 lb-ft = 456 kip-in B2 −M = +M = −M = WB2 l2 11 WB2 l2 16 WB2 l2 11 = = = 1672∗17.52 11 1672∗17.52 16 1672∗17.52 11 = 46550 lb-ft = 559 kip-in = 32003 lb-ft = 384 kip-in = 46550 lb-ft = 559 kip-in B3 −M = +M = −M = WB3 l2 10 WB3 l2 14 WB3 l2 16 = = = 1533∗15.752 10 1533∗15.752 14 1533∗15.752 16 = 38028 lb-ft = 456 kip-in = 27163 lb-ft = 326 kip-in = 23768 lb-ft = 285 kip-in 3.6.2 Grid 2 B4 −M = +M = −M = WB4 l2 16 WB4 l2 14 WB4 l2 10 = = = 2781∗15.752 16 2781∗15.752 14 2781∗15.752 10 = 43116 lb-ft = 517 kip-in = 49276 lb-ft = 591 kip-in = 68986 lb-ft = 828 kip-in B5 −M = +M = −M = WB5 l2 11 WB5 l2 16 WB5 l2 11 = = = 3041∗17.52 11 3041∗17.52 16 3041∗17.52 11 = 84664 lb-ft = 1016 kip-in = 58207 lb-ft = 699 kip-in = 84664 lb-ft = 1016 kip-in 19 B6 −M = +M = −M = WB6 l2 10 WB6 l2 14 WB6 l2 16 = = = 2780∗15.752 10 2780∗15.752 14 2780∗15.752 16 = 76624 lb-ft = 920 kip-in = 49258 lb-ft = 591 kip-in = 43101 lb-ft = 517 kip-in 3.6.3 Grid 1 B7 −M = +M = −M = WB7 l2 16 WB7 l2 14 WB7 l2 9 = = = 1655∗17.52 16 1655∗17.52 14 1655∗17.52 9 = 31678 lb-ft = 380 kip-in = 36203 lb-ft = 434 kip-in = 56316 lb-ft = 676 kip-in B8 −M = +M = −M = WB8 l2 9 WB8 l2 14 WB8 l2 16 = = = 1532∗15.752 9 1532∗15.752 14 1532∗15.752 16 = 42226 lb-ft = 507 kip-in = 27145 lb-ft = 326 kip-in = 23752 lb-ft = 285 kip-in 3.6.4 Grid D B9 −M = +M = −M = WB9 l2 16 WB9 l2 14 WB9 l2 9 = = = 1674∗17.752 16 1674∗17.752 14 1674∗17.752 9 = 32963 lb-ft = 396 kip-in = 37672 lb-ft = 452 kip-in = 58602 lb-ft = 703 kip-in B10 −M = +M = WB10 l2 9 WB10 l2 14 = = 1494∗15.252 9 1494∗15.252 14 = 38605 lb-ft = 463 kip-in = 24818 lb-ft = 298 kip-in 20 −M = WB10 l2 16 = 1494∗15.252 16 = 21716 lb-ft = 261 kip-in 3.6.5 Grid C B11 −M = +M = −M = WB11 l2 16 WB11 l2 14 WB11 l2 9 = = = 3087∗17.752 16 3087∗17.752 14 3087∗17.752 9 = 60787 lb-ft = 730 kip-in = 69471 lb-ft = 834 kip-in = 108066 lb-ft = 1297 kip-in B12 −M = +M = −M = WB12 l2 9 WB12 l2 14 WB12 l2 16 = = = 2702∗15.252 9 2702∗15.252 14 2702∗15.252 16 = 69820 lb-ft = 838 kip-in = 44885 lb-ft = 539 kip-in = 39274 lb-ft = 471 kip-in 3.6.6 Grid B B13 −M = +M = −M = WB13 l2 16 WB13 l2 14 WB13 l2 9 = = = 3087∗17.752 16 3087∗17.752 14 3087∗17.752 9 = 60787 lb-ft = 730 kip-in = 69471 lb-ft = 834 kip-in = 108066 lb-ft = 1297 kip-in B14 −M = +M = −M = WB14 l2 9 WB14 l2 14 WB14 l2 16 = = = 2702∗15.252 9 2702∗15.252 14 2702∗15.252 16 = 69820 lb-ft = 838 kip-in = 44885 lb-ft = 539 kip-in = 39274 lb-ft = 471 kip-in 21 3.6.7 Grid A B15 −M = +M = −M = WB15 l2 16 WB15 l2 14 WB15 l2 9 = = = 1674∗17.752 16 1674∗17.752 14 1674∗17.752 9 = 32964 lb-ft = 396 kip-in = 37673 lb-ft = 452 kip-in = 58602 lb-ft = 703 kip-in 3.7 Size determination and reinforcement calculation 3.7.1 Grid C Beam ID: B11 & B12 -Mmax = 1297 kip-in ø=0.9 Mu d = √( ) øRb ρ = 0.85 ∗ β ∗ d = √( 1297 ) 0.9 ∗ 0.912 ∗ 12 f′c €c ∗ fy €c + €t ρ = 0.85 ∗ 0.85 ∗ 4 0.003 ∗ 60 0.003 + 0.005 ρ= 0.0181 d= 11.48" ρ ∗ fy ) f ′c Total depth “h” = d+ clear cover R = ρ ∗ fy ∗ (1 − 0.588 ∗ h= 11.48"+2.5" R = 0.0181 ∗ 60 ∗ (1 − 0.588 ∗ h=13.98 ≈ 14" (So ok) 0.0181 ∗ 60 ) 4 R= 0.912 ksi Effective Depth d = 14"-2.5" d= 11.50" Check for Singly or Doubly Beam: M= *R*b*d2 M=0 .9*0.912*12*11.502 M= 1303 kip-in > Mu So it is singly reinforcement beam. Let, a= 3.65" As = Mu a ø ∗ fy ∗ (d − 2) 22 1297 As = 0.9 ∗ 60 ∗ (11.5 – 3.65 2 ) As= 2.48 in2 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ b a= 2.48 ∗ 60 0.85 ∗ 4 ∗ 12 a= 3.65" C= a 3.65 = = 4.30 in β1 0.85 ∈t =∈u × d−C C ∈t = 0.003 × 12.5 − 4.30 4.30 ∈t = 0.00502 So ∈t = 0.005 (ok) So As= 2.48 in2 ∴ Beam size = 12" X 14" Design of T beam +Mmax = 834 kip-in Calculation effective width of flange a) ¼ * Span = ¼ *17.75*12 = 53.24 ≈ 54 in b) bw+16*t = 12+16*5 = 92 in c) Spacing of beam = 15*12 =180 in ∴ bf = 54 in Let, a = 0.45 834 As = 0.9 ∗ 60 ∗ (11.5 – 0.45 ) 2 As = 1.37 in2 23 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ bf a= 1.37 ∗ 60 0.85 ∗ 4 ∗ 54 a= 0.45" ∴ As = 1.37 in 3.7.2 Grid A Beam ID: B15 -Mmax = 703 kip-in ø=0.9 Mu d = √( ) øRb d = √( ρ = 0.85 ∗ β ∗ 703 ) 0.9 ∗ 0.912 ∗ 12 f′c €c ∗ fy €c + €t ρ = 0.85 ∗ 0.85 ∗ 4 0.003 ∗ 60 0.003 + 0.005 d= 8.45" ρ= 0.0181 Total depth “h” = d+ clear cover R = ρ ∗ fy ∗ (1 − 0.588 ∗ ρ ∗ fy ) f ′c h= 8.45"+2.5" h=10.95 ≈ 12" (So ok) Effective Depth d = 12"-2.5" R = 0.0181 ∗ 60 ∗ (1 − 0.588 ∗ 0.0181 ∗ 60 ) 4 R= 0.912 ksi d= 9.5" Check for Singly or Doubly Beam: M= *R*b*d2 M=0 .9*0.912*12*9.52 M= 889 kip-in > Mu So it is singly reinforcement beam. Let, a= 2.30" As = As = Mu a ø ∗ fy ∗ (d − 2) 703 0.9 ∗ 60 ∗ (9.5 – 2.30 2 ) 24 As= 1.56 in2 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ b a= 1.65 ∗ 60 0.85 ∗ 4 ∗ 12 a= 2.30" C= a 2.30 = = 2.71 in β1 0.85 ∈t =∈u × d−C C ∈t = 0.003 × 9.5 − 2.71 2.71 ∈t = 0.0075 So ∈t = 0.005 (ok) So As= 1.56 in2 ∴ Beam size = 12" X 12" (Note: The minimum width of a beam should be 12 inches. Bibliography No. 11) +Mmax = 452 kip-in As= 0.89 in2 Similarly 3.7.3 Grid B Beam ID: B13 & B14 -Mmax = 1297 kip-in Mu d = √( ) øRb d = √( ø=0.9 R= 0.912 ksi 1297 ) 0.9 ∗ 0.912 ∗ 12 d= 11.48" Total depth “h” = d+ clear cover 25 h= 11.48"+2.5" h=13.98 ≈ 14" (So ok) Effective Depth d = 14"-2.5" d= 11.50" As = Mu a ø ∗ fy ∗ (d − 2) 1297 As = 0.9 ∗ 60 ∗ (11.5 – 3.65 2 ) As= 2.48 in2 ∴ Beam size = 12" X 14" +Mmax = 834 kip-in As= 1.37 in2 3.7.4 Grid D Beam ID: B9 & B10 -Mmax = 703 kip-in d = √( Mu ) øRb d = √( 703 ) 0.9 ∗ 0.912 ∗ 12 d= 8.45" Total depth “h” = d+ clear cover h= 8.45"+2.5" h=10.95 ≈ 12" (So ok) Effective Depth d = 12"-2.5" d= 9.5" Let, a= 2.30" As = Mu a ø ∗ fy ∗ (d − 2) 26 703 As = 0.9 ∗ 60 ∗ (9.5 – 2.30 2 ) As= 1.56 in2 ∴ Beam size = 12" X 12" +Mmax = 452 kip-in As= 0.89 in2 3.7.5 Grid 1 Beam ID: B7 & B8 -Mmax = 676 kip-in d = √( Mu ) øRb d = √( 676 ) 0.9 ∗ 0.912 ∗ 12 d= 8.30" Total depth “h” = d+ clear cover h= 8.30"+2.5" h=10.8 ≈ 12" (So ok) Effective Depth d = 12"-2.5" d= 9.5" 676 As = 0.9 ∗ 60 ∗ (9.5 – 2.20 2 ) As= 1.50 in2 ∴ Beam size = 12" X 12" +Mmax = 434 kip-in As= 0.86 in2 27 3.7.6 Grid 2 Beam ID: B4, B5 & B6 -Mmax = 1016 kip-in d = √( Mu ) øRb d = √( 1016 ) 0.9 ∗ 0.912 ∗ 12 d= 10.16" Total depth “h” = d+ clear cover h= 10.16"+2.5" h=12.66 ≈ 14" (So ok) Effective Depth d = 14"-2.5" d= 11.5" 1016 As = 0.9 ∗ 60 ∗ (11.5 – 2.73 2 ) As= 1.86 in2 ∴ Beam size = 12" X 14" +Mmax = 699 kip-in As= 1.14 in2 3.7.7 Grid 3 Beam ID: B1, B2 & B3 -Mmax = 559 kip-in d = √( Mu ) øRb d = √( 559 ) 0.9 ∗ 0.912 ∗ 12 d= 7.53" Total depth “h” = d+ clear cover h= 7.53"+2.5" 28 h=10.03 ≈ 12" (So ok) Effective Depth d = 12"-2.5" d= 9.5" 559 As = 0.9 ∗ 60 ∗ (9.5 – 1.76 2 ) As= 1.20 in2 ∴ Beam size = 12" X 12" +Mmax = 384 kip-in As= 0.76 in2 Table 3.1 Summary of the beam design for without lateral load condition Beam ID Beam Size B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 B13 B14 B15 12" X 12" 12" X 12" 12" X 12" 12" X 14" 12" X 14" 12" X 14" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 12" X 14" 12" X 14" 12" X 14" 12" X 14" 12" X 12" Positive Steel Area in in2 0.64 0.76 0.64 0.97 1.14 0.97 0.86 0.64 0.89 0.60 1.37 0.89 1.37 0.89 0.89 Negative Steel Area in in2 0.98 1.20 0.98 1.51 1.86 1.70 1.50 1.12 1.56 1.03 2.48 1.61 2.48 1.61 1.56 29 CHAPTER-IV COLUMN DESIGN WITHOUT LATERAL LOAD 4.1 Loading area calculation of columns CA1 = ( 17.75 15.75 )∗( ) = 69.89 ft 2 2 2 CA2 = ( 15.75 + 17.5 17.75 )∗( ) = 147.55 ft 2 2 2 CA3 = ( 15.75 + 17.5 17.75 )∗( ) = 147.55 ft 2 2 2 CA4 = ( 17.75 15.75 )∗( ) = 69.89 ft 2 2 2 CA5 = ( 17.75 + 15.25 15.75 )∗( ) = 129.94 ft 2 2 2 CA6 = ( 17.75 + 15.25 15.75 + 17.5 )∗( ) = 274.31 ft 2 2 2 CA7 = ( 17.75 + 15.25 15.75 + 17.5 )∗( ) = 274.31 ft 2 2 2 CA8 = ( 17.75 + 15.25 15.75 )∗( ) = 129.94 ft 2 2 2 CA9 = ( 15.25 15.75 )∗( ) = 60 ft 2 2 2 17.5 + 15.75 15.25 CA10 = ( )∗( ) = 126.77 ft 2 2 2 17.5 + 15.75 15.25 CA11 = ( )∗( ) = 126.77 ft 2 2 2 15.25 15.75 CA12 = ( )∗( ) = 60 ft 2 2 2 30 4.1.1 Beam load Beam size Beam Stem Load Per ft 12"X12" 12 ∗ 7 ∗ 150 = 87.5 lb/ft 144 12"X14" 12 ∗ 9 ∗ 150 = 112.5 lb/ft 144 12"X15" 12 ∗ 10 ∗ 150 = 125 lb/ft 144 4.1.2 Self wt of Column Column size Column load/floor 12"X12" 12 ∗ 12 ∗ 9.5 ∗ 150 = 1425 lb 144 15"X15" 15 ∗ 15 ∗ 9.5 ∗ 150 = 2227 lb 144 20"X20" 20 ∗ 20 ∗ 9.5 ∗ 150 = 3958 lb 144 24"X24" 24 ∗ 24 ∗ 9.5 ∗ 150 = 5700 lb 144 4.2 Load calculation on column for 1st storey C1 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 15.75 C2 = {147.55 ∗ 317 + 87.5 ∗ ( 17.75 + 87.5 ∗ 2 + 2 + 1425) ∗ 10 = 250457 lb = 250 kips 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 10 = 512316 lb = 512 kips 15.75 C3 = {147.55 ∗ 317 + 87.5 ∗ ( 2 + 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 10 = 512316 lb = 512 kips C4 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 17.75 C5 = {129.94 ∗ 317 + 87.5 ∗ ( 17.75 + 87.5 ∗ 2 + 2 + 1425) ∗ 10 = 250457 lb = 250 kips 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 10 = 457476 lb = 458 kips C6 = {274.31 ∗ 317 + 125 ∗ ( 17.75 2 + 15.25 15.75 2 2 ) + 112.5 ∗ ( + 17.5 2 ) + 5700} ∗ 10 = 965891 lb = 966 kips 31 15.75 C7 = {274.31 ∗ 317 + 112.5 ∗ ( 2 ∗ 17.5 17.75 2 2 ) + 125 ∗ ( + 15.25 2 ) + 5700} ∗ 10 = 965891 lb = 966 kips 17.75 C8 = {129.94 ∗ 317 + 87.5 ∗ ( 2 + 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 10 = 457476 lb = 458 kips C9 = (60 ∗ 317 + 87.5 ∗ 15.25 2 + 87.5 ∗ 9 + 1425) ∗ 10 = 218997 lb = 219 kips C10 = {126.77 ∗ 317 + 87.5 ∗ C11 = {126.77 ∗ 317 + 87.5 ∗ 15.25 2 15.25 2 + 87.5 ∗ ( + 87.5 ∗ ( 17.5 2 ) + 2227} ∗ 10 = 438460 lb = 439 kips 15.75 2 + 17.5 2 ) + 2227} ∗ 10 = 445350 lb = 445 kips C12 = (60 ∗ 317 + 87.5 ∗ 15.25 2 + 87.5 ∗ 15.75 2 + 1425) ∗ 10 = 218013 lb = 218 kips 4.3 Column design for 1st storey 4.3.1 Column ID: C6 & C7 Load Pn = 966 kips Assume Column size=20"X20" ACI code specifies 0.01 ≤ ρg ≤ 0.08 Using ρg=0.03 Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 400 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 1060.5 kips > 966 kips so ok AS = ρ ∗ Ag = 0.03 ∗ 400 = 12 in2 4.3.2 Column ID: C1, C4, C9 & C12 Load Pn = 250 kips Assume Column size=12"X12" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 144 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 381 kips > 250 kips so ok AS = ρ ∗ Ag = 0.03 ∗ 144 = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) 32 4.3.3 Column ID: C2 & C3 Load Pn = 512 kips Assume Column size=12"X15" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 180 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 477 kips < 512 kips not ok Assume Column size=12"X18" Pu = 0.80 ∗ 0.65 ∗ 216 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 573 kips > 512 kips So ok AS = ρ ∗ Ag = 0.03 ∗ 216 = 6.48 in2 4.3.4 Column ID: C5, C8, C10 & C11 Load Pn = 458 kips Assume Column size=12"X16" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 192 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 509 kips > 458 kips So ok AS = ρ ∗ Ag = 0.03 ∗ 192 = 5.76 in2 4.4 Load calculation on column for 3rd storey C1 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 + 87.5 ∗ 15.75 C2 = {147.55 ∗ 317 + 87.5 ∗ ( 2 + 17.75 2 + 1425) ∗ 7 = 175320 lb = 175 kips 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 7 = 358621 lb = 359 kips 15.75 C3 = {147.55 ∗ 317 + 87.5 ∗ ( 2 + 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 7 = 358621 lb = 359 kips C4 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 + 87.5 ∗ 17.75 2 + 1425) ∗ 7 = 175320 lb = 175 kips 33 17.75 C5 = {129.94 ∗ 317 + 87.5 ∗ ( + 2 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 7 = 320234 lb = 320 kips C6 = {274.31 ∗ 317 + 125 ∗ ( 17.75 2 + 15.25 15.75 2 2 ) + 112.5 ∗ ( + 17.5 ) + 5700} ∗ 7 = 676124 lb 2 = 676 kips 15.75 C7 = {274.31 ∗ 317 + 112.5 ∗ ( 2 ∗ 17.5 17.75 2 2 ) + 125 ∗ ( + 15.25 2 ) + 5700} ∗ 7 = 676124 lb = 676 kips 17.75 C8 = {129.94 ∗ 317 + 87.5 ∗ ( 2 + 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 7 = 320234 lb = 320 kips C9 = (60 ∗ 317 + 87.5 ∗ 15.25 2 + 87.5 ∗ 9 + 1425) ∗ 7 = 153298 lb = 153 kips C10 = {126.77 ∗ 317 + 87.5 ∗ C11 = {126.77 ∗ 317 + 87.5 ∗ C12 = (60 ∗ 317 + 87.5 ∗ 15.25 2 15.25 2 15.25 2 + 87.5 ∗ ( + 87.5 ∗ ( + 87.5 ∗ 15.75 2 17.5 2 ) + 2227} ∗ 10 = 214845 lb = 215 kips 15.75 2 + 17.5 2 ) + 2227} ∗ 7 = 218222 lb = 218 kips + 1425) ∗ 7 = 106826 lb = 107 kips 4.5 Column design for 3rd storey 4.5.1 Column ID: C6 & C7 Load Pn = 676 kips Assume Column size=16"X16" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 256 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 679 kips > 676 ππππ so ok AS = ρ ∗ Ag = 0.03 ∗ 256 = 7.68 in2 34 4.5.2 Column ID: C1, C4, C9 & C12 Load Pn = 175 kips Assume Column size=12"X12" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 144 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 382 kips > 175 kips so ok AS = ρ ∗ Ag = 0.03 ∗ 144 = 4.32 in2 4.5.3 Column ID: C2 & C3 Load Pn = 359 kips Assume Column size=12"X12" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 144 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 382 kips > 359 kips So ok AS = ρ ∗ Ag = 0.03 ∗ 144 = 4.32 in2 4.5.4 Column ID: C5, C8, C10 & C11 Load Pn = 320 kips Assume Column size=12"X12" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 144 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 382 kips > 320 kips So ok AS = ρ ∗ Ag = 0.03 ∗ 144 = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) 35 4.6 Load calculation on column for 5th storey C1 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 15.75 C2 = {147.55 ∗ 317 + 87.5 ∗ ( 17.75 + 87.5 ∗ + 2 2 + 1425) ∗ 5 = 125229 lb = 125 kips 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 5 = 256158 lb = 256 kips 15.75 C3 = {147.55 ∗ 317 + 87.5 ∗ ( + 2 17.5 17.75 2 2 ) + 87.5 ∗ + 2227} ∗ 5 = 256158 lb = 256 kips C4 = (69.89 ∗ 317 + 87.5 ∗ 15.75 2 17.75 C5 = {129.94 ∗ 317 + 87.5 ∗ ( 17.75 + 87.5 ∗ + 2 2 + 1425) ∗ 5 = 125229 lb = 125 kips 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 5 = 228738 lb = 229 kips C6 = {274.31 ∗ 317 + 125 ∗ ( 17.75 2 + 15.25 15.75 2 2 ) + 112.5 ∗ ( + 17.5 ) + 5700} ∗ 5 2 = 482945.4 lb = 483 kips 15.75 C7 = {274.31 ∗ 317 + 112.5 ∗ ( 2 ∗ 17.5 17.75 2 2 ) + 125 ∗ ( + 15.25 2 ) + 5700} ∗ 5 = 482945.4 lb = 483 kips 17.75 C8 = {129.94 ∗ 317 + 87.5 ∗ ( 2 + 15.25 15.75 2 2 ) + 112.5 ∗ + 2227} ∗ 5 = 228738 lb = 229 kips C9 = (60 ∗ 317 + 87.5 ∗ 15.25 2 + 87.5 ∗ 9 + 1425) ∗ 5 = 109499 lb = 110 kips C10 = {126.77 ∗ 317 + 87.5 ∗ C11 = {126.77 ∗ 317 + 87.5 ∗ 15.25 2 15.25 2 + 87.5 ∗ ( + 87.5 ∗ ( 17.5 2 ) + 2227} ∗ 5 = 219230 lb = 219 kips 15.75 2 + 17.5 2 ) + 2227} ∗ 5 = 222675 lb = 223 kips C12 = (60 ∗ 317 + 87.5 ∗ 15.25 2 + 87.5 ∗ 15.75 2 + 1425) ∗ 5 = 109007 lb = 110 kips 36 4.7 Column design for 5th storey 4.7.1 Column ID: C6 & C7 Load Pn = 483 kips Assume Column size=14"X14" Pu = φPn(max) = 0.80φAg [0.85fc′ (1 − ρg ) + ρfy ] Pu = 0.80 ∗ 0.65 ∗ 196 ∗ {0.85 ∗ 4 ∗ (1 − 0.03) + 0.03 ∗ 60} = 520 kips > 483 kips so ok AS = ρ ∗ Ag = 0.03 ∗ 196 = 5.88 in2 4.7.2 All columns are minimum size = 12" X 12" Steel area is, AS = ρ ∗ Ag = 0.03 ∗ 144 = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) Table 4.1 Column design summary without lateral load condition Column ID C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 Steel Area in in2 Column Size 1st Storey 12" X 12" 12" X 18" 12" X 18" 12" X 12" 12" X 16" 20" X 20" 20" X 20" 12" X 16" 12" X 12" 12" X 16" 12" X 16" 12" X 12" 3rd Storey 12" X 12" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 16" X 16" 16" X 16" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 5th Storey 12" X 12" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 14" X 14" 14" X 14" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 12" X 12" 1st Storey 4.32 6.48 6.48 4.32 5.76 12 12 5.76 4.32 5.76 5.76 4.32 3rd Storey 4.32 4.32 4.32 4.32 4.32 7.68 7.68 4.32 4.32 4.32 4.32 4.32 5th Storey 4.32 4.32 4.32 4.32 4.32 5.88 5.88 4.32 4.32 4.32 4.32 4.32 37 CHAPTER-V ETABS ANALYSIS 5.1 Introduction of ETABS ETABS will continue to be the professional engineer's choice for an end-to-end, multi-material structural software solution. For static, dynamic, P-delta, non-linear, buckling or cable analysis, ETABS is the industry standard. Complex models can be quickly and easily generated through powerful graphics, text and spreadsheet interfaces that provide true interactive model generation, editing, and analysis. ETABS easily generates comprehensive custom reports for management, architects, owners, etc. Reports contain only the information you want, where you want it. Add your own logo as well as graphical input and output results. Export all data to Microsoft Word. The analysis of the building has done by computer software ETABS for 3D analysis of the structure. A manual design has been done by USD methods for design beam & column. 5.2 Modeling a building by ETABS Step-1: Geometry New page-File- New modal Building plan Grid system and spacing-Grid only-Edit Grid Unit – (kip-ft) X Grid Display Grid as Spacing Bubble size-(60) Y grid- Same as Simple story data No of story-11 Typical story height-10 ft Bottom story height-8 ft Ok 38 Step-2: Assign property Column Define Frame section Add rectangular Section name (CC) Material Properties (Column) Dimension-Depth (12)-Width (12) Reinforcement Design Type (column) Check/Design-(Reinforcement to be designed), Ok (Define Beam, Slab, and Share Wall as same) Step-3: Insert support Support Selects below all column Column symbol select Assign Restrain First restrain Fixed Ok Step-4: Assign load Define Static load Cases Type Dead load select Load (DL) Add new load- (Ok) 39 Modify load- (OK) (Define LL and WL same as) Step-5: Load combination Define Load combinations Add New Combination Data Case name (like as DEAD static load) Scale Factor (like as 1.2) Add Ok 5.3 Analysis of a ten storied frame structure residential building Analyze Check model (all select) Ok Analyze Run analysis Ok Beam moment and Shear force out put Display Show member forces/stress diagram Frame/Pier/Spandrel forces Load (Com-1) Beam moment (3-3) Show value OK 40 Fig. 5.1.1 Three dimensional view on ETABS 41 Fig. 5.1.2 Axial force diagram 42 Fig. 5.1.3 Bending moment diagram 43 5.4 Summary after analysis by ETABS Table 5.1 Maximum moment on beams Beam ID B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 B13 B14 B15 Positive Moment (Max) in kip-in 629 392 566 660 868 762 721 317 620 818 1059 1031 969 680 356 Negative Moment (Max) in kip-in 1258 783 1133 1319 1736 1525 1442 633 610 1636 2119 2062 1938 1359 712 Table 5.2 Data for column 1st Story Column ID 3rd Story 5th Story C1 Vertical Mx Load in in kips kip-in 340 326 My in kip-in 689 Vertical Mx Load in in kips kip-in 285 548 My Vertical Mx in Load in in kip-in kips kip-in 471 209 614 My in kip-in 386 C2 686 776 782 543 1119 619 404 1135 460 C3 702 674 800 565 1120 644 406 1250 463 C4 378 939 363 309 982 296 232 920 223 C5 359 672 562 320 153 95 193 160 70 C6 1385 1828 916 1229 1229 339 490 827 273 C7 1473 1945 85 1179 1556 345 484 248 499 C8 609 953 875 482 574 905 356 404 861 C9 220 167 216 88 129 286 71 75 290 C10 440 191 565 225 224 350 98 29 38 C11 538 963 613 410 917 467 291 775 331 C12 337 822 324 262 794 252 188 180 242 44 CHAPTER-VI BEAM DESIGN WITH LATERAL LOAD 6.1 Beams design with lateral load conditions 6.1.1 Grid C Beam ID: B11 & B12 -Mmax = 2119 kip-in ø=0.9 Mu d = √( ) øRb ρ = 0.85 ∗ β ∗ 2119 ) 0.9 ∗ 0.912 ∗ 12 d= 14.67" d = √( Total depth “h” = d+ clear cover f′c €c ∗ fy €c + €t ρ = 0.85 ∗ 0.85 ∗ 4 0.003 ∗ 60 0.003 + 0.005 ρ= 0.0181 R = ρ ∗ fy ∗ (1 − 0.588 ∗ h= 14.67"+2.5" ρ ∗ fy ) f ′c h=17.17 ≈ 18" (So ok) R = 0.0181 ∗ 60 ∗ (1 − 0.588 ∗ Effective Depth d = 18"-2.5" R= 0.912 ksi 0.0181 ∗ 60 ) 4 d= 15.50" Check for Singly or Doubly Beam: M= *R*b*d2 M=0 .9*0.912*12*15.502 M= 2366 kip-in > Mu So it is singly reinforcement beam. Let, a= 4.32" As = Mu a ø ∗ fy ∗ (d − 2) 2119 As = 0.9 ∗ 60 ∗ (15.5 – 4.32 2 ) As= 2.94 in2 45 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ b a= 2.94 ∗ 60 0.85 ∗ 4 ∗ 12 a= 4.32" C= a 4.32 = = 5.10 in β1 0.85 ∈t =∈u × d−C C ∈t = 0.003 × 15.5 − 5.10 5.10 ∈t = 0.0061 So ∈t = 0.005 (ok) So As= 2.94 in2 ∴ Beam size = 12" X 18" Design of T beam +Mmax = 1059 kip-in Calculation effective width of flange a) ¼ * Span = ¼ *17.75*12 = 53.24 ≈ 54 in b) bw+16*t = 12+16*5 = 92 in c) Spacing of beam = 15*12 =180 in ∴ bf = 54 in a = 0.42 1059 As = 0.9 ∗ 60 ∗ (15.5 – 0.42 2 ) As= 1.28 in2 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ bf a= 1.28 ∗ 60 0.85 ∗ 4 ∗ 54 46 a= 0.42" ∴ As = 1.28 in 6.1.2 Grid A Beam ID: B15 -Mmax = 712 kip-in ø=0.9 Mu d = √( ) øRb ρ = 0.85 ∗ β ∗ f′c €c ∗ fy €c + €t 712 ) 0.9 ∗ 0.912 ∗ 12 d= 8.51" ρ = 0.85 ∗ 0.85 ∗ Total depth “h” = d+ clear cover ρ= 0.0181 d = √( 4 0.003 ∗ 60 0.003 + 0.005 R = ρ ∗ fy ∗ (1 − 0.588 ∗ h= 8.51"+2.5" h=11.01 ≈ 12" (So ok) ρ ∗ fy ) f ′c R = 0.0181 ∗ 60 ∗ (1 − 0.588 ∗ Effective Depth d = 12"-2.5" 0.0181 ∗ 60 ) 4 R= 0.912 ksi d= 9.5" Check for Singly or Doubly Beam: M= *R*b*d2 M=0 .9*0.912*12*9.52 M= 889 kip-in > Mu So it is singly reinforcement beam. Let, a= 2.35" As = Mu a ø ∗ fy ∗ (d − 2) 712 As = 0.9 ∗ 60 ∗ (9.5 – 2.50 2 ) As= 1.60 in2 Check a: As ∗ fy a= 0.85 ∗ f`c ∗ b a= 1.6 ∗ 60 0.85 ∗ 4 ∗ 12 47 a= 2.35" C= a 2.35 = = 2.76 in β1 0.85 ∈t =∈u × d−C C ∈t = 0.003 × 9.5 − 2.76 2.76 ∈t = 0.007 So ∈t = 0.005 (ok) So As= 1.60 in2 ∴ Beam size = 12" X 12" (Note: The minimum width of a beam should be 12 inches. Bibliography No. 11) +Mmax = 356 kip-in As= 0.80 in2 Similarly 6.1.3 Grid B Beam ID: B13 & B14 -Mmax = 1938 kip-in Mu d = √( ) øRb ø=0.9 R= 0.912 ksi 1938 ) 0.9 ∗ 0.912 ∗ 12 d= 11.61" d = √( Total depth “h” = d+ clear cover h= 14.03"+2.5" h=16.53 ≈ 18" (So ok) Effective Depth d = 18"-2.5" d= 15.5" 48 As = Mu a ø ∗ fy ∗ (d − 2) 1938 As = 0.9 ∗ 60 ∗ (15.5 – 4.20 2 ) As= 2.70 in2 ∴ Beam size = 12" X 18" +Mmax = 969 kip-in As= 1.35 in2 6.1.4 Grid D Beam ID: B9 & B10 -Mmax = 1636 kip-in d = √( Mu ) øRb 1636 ) 0.9 ∗ 0.912 ∗ 12 d= 12.89" d = √( Total depth “h” = d+ clear cover h= 12.89"+2.5" h=15.39 ≈ 16" (So ok) Effective Depth d = 16"-2.5" d= 13.5" 1636 As = 0.9 ∗ 60 ∗ (13.5 – 3.85 2 ) As= 2.62 in2 ∴ Beam size = 12" X 16" +Mmax = 818 kip-in As= 1.14 in2 6.1.5 Grid 1 Beam ID: B7 & B8 -Mmax = 1442 kip-in 49 d = √( Mu ) øRb 1442 ) 0.9 ∗ 0.912 ∗ 12 d= 12.1" d = √( Total depth “h” = d+ clear cover h= 12.1"+2.5" h=14.6 ≈ 15" (So ok) Effective Depth d = 15"-2.5" d= 12.5" 1442 As = 0.9 ∗ 60 ∗ (12.5 – 3.70 2 ) As= 2.51 in2 ∴ Beam size = 12" X 15" +Mmax = 721 kip-in As= 1.08 in2 6.1.6 Grid 2 Beam ID: B4, B5 & B6 -Mmax = 1736 kip-in d = √( Mu ) øRb 1736 ) 0.9 ∗ 0.912 ∗ 12 d= 13.28" d = √( Total depth “h” = d+ clear cover h= 13.28"+2.5" h=15.78 ≈ 16" (So ok) Effective Depth d = 16"-2.5" d= 13.5" 50 As = 1736 4.1 0.9 ∗ 60 ∗ (13.5 – 2 ) As= 2.81 in2 ∴ Beam size = 12" X 16" +Mmax = 868 kip-in As= 1.21 in2 6.1.7 Grid 3 Beam ID: B1, B2&B3 -Mmax = 1258 kip-in d = √( Mu ) øRb 1258 ) 0.9 ∗ .912 ∗ 12 d= 11.30" d = √( Total depth “h” = d+ clear cover h= 11.30"+2.5" h=13.80 ≈ 14" (So ok) Effective Depth d = 14"-2.5" d= 11.50" As = Mu a ø ∗ fy ∗ (d − ) 2 1258 As = 0.9 ∗ 60 ∗ (11.50 – 3.50 2 ) So As= 2.40 in2 ∴ Beam size = 12" X 14" +Mmax = 629 kip-in As= 1.03 in2 51 Table 6.1 Summary of the beam design for with lateral load condition Beam ID Beam Size B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 B13 B14 B15 12" X 14" 12" X 14" 12" X 14" 12" X 16" 12" X 16" 12" X 16" 12" X 15" 12" X 15" 12" X 16" 12" X 16" 12" X 18" 12" X 18" 12" X 18" 12" X 18" 12" X 12" Positive Steel Area in in2 1.03 0.75 0.93 1.07 1.21 1.05 1.08 0.55 1.00 1.14 1.28 1.44 1.35 0.94 0.80 Negative Steel Area in in2 2.40 1.49 2.16 2.13 2.81 2.47 2.51 1.10 1.00 2.62 2.94 2.86 2.70 1.88 1.60 52 CHAPTER-VII COLUMN DESIGN WITH LATERAL LOAD 7.1 For 1st storey column design Column ID: C1 Assume Column size=14"X14" Ag = 14 X 14 = 196 in2 ρ = 0.03 Pu = 340 kips MX = 326 kip-in My = 689 kip-in ex = MX 326 = = 0.959 in Pu 340 ey = My 689 = = 2.026 in Pu 340 ex = 0 γ= 14 − 5 = 0.64 14 ey 2.026 = = 0.1447 h 14 Pnx0 = 0.8629 ∗ 4 ∗ 196 = 676.48 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 0.959 = = 0.064 h 14 Pny0 = 1.071 ∗ 4 ∗ 196 = 840 kips P0 = 1.27 ∗ 4 ∗ 196 = 995.69 kips 53 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 676.48 840 995.69 Pn = 600.82 kips Pu = 0.65 X 600.84 = 390 kips > 340 ππππ (ππ ππ) ∴ As = ρAg = 0.03 X 196 = 5.88 in2 Column ID: C2 Assume Column size=14"X20" Ag = 14 X 20 = 280 in2 ρ = 0.03 Pu = 686 kips MX = 776 kip-in My = 782 kip-in ex = MX 776 = = 1.13 in Pu 686 ey = My 782 = = 1.14 in Pu 686 ex = 0 γ= 20 − 5 = 0.75 20 ey 1.14 = = 0.06 h 20 Pnx0 = 1.1 ∗ 4 ∗ 280 = 1232 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 1.13 = = 0.08 h 14 Pny0 = 1.069 ∗ 4 ∗ 280 = 1197 kips 54 P0 = 1.27 ∗ 4 ∗ 280 = 1422 kips 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 1232 1197 1422 Pn = 1059.08 kips Pu = 0.65 X 1059.08 = 688.4 kips > 686 ππππ (ππ ππ) ∴ As = ρAg = 0.03 X 280 = 8.4 in2 Similarly Column ID: C3 Column size=15"X20" ∴ As = 9.00 in2 Column ID: C4 Column size=15"X15" ∴ As = 6.75 in2 Column ID: C5 Column size=14"X16" ∴ As = 6.72 in2 Column ID: C6 Column size=24"X24" ∴ As = 17.28 in2 Column ID: C7 Column size=24"X24" ∴ As = 17.28 in2 Column ID: C8 Column size=16"X20" ∴ As = 9.60 in2 55 Column ID: C9 Column size=12"X12" ∴ As = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) Column ID: C10 Column size=14"X18" ∴ As = 7.56 in2 Column ID: C11 Column size=14"X20" ∴ As = 8.4 in2 Column ID: C12 Column size=14"X14" ∴ As = 5.88 in2 56 7.2 For 3rd storey column design Column ID: C1 Assume Column size=14"X14" Ag = 14 X 14 = 196 in2 ρ = 0.03 Pu = 285 kips MX = 548 kip-in My = 471 kip-in ex = MX 548 = = 1.923 in Pu 285 ey = My 471 = = 1.653 in Pu 285 ex = 0 γ= 14 − 5 = 0.64 14 ey 1.653 = = 0.118 h 14 Pnx0 = 0.918 ∗ 4 ∗ 196 = 720.16 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 1.923 = = 0.14 h 14 Pny0 = 0.889 ∗ 4 ∗ 196 = 687 kips P0 = 1.27 ∗ 4 ∗ 196 = 995.69 kips 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 720.16 687 995.69 Pn = 549.54 kips Pu = 0.65 X 549.54 = 357 kips > 285 ππππ (ππ ππ) 57 ∴ As = ρAg = 0.03 X 196 = 5.88 in2 Column ID: C2 Assume Column size=14"X20" Ag = 14 X 20 = 280 in2 ρ = 0.03 Pu = 543 kips MX = 1119 kip-in My = 619 kip-in ex = MX 1119 = = 2.06 in Pu 543 ey = My 619 = = 1.14 in Pu 543 ex = 0 γ= 20 − 5 = 0.75 20 ey 1.14 = = 0.06 h 20 Pnx0 = 1.12 ∗ 4 ∗ 280 = 1254 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 2.06 = = 0.15 h 14 Pny0 = 0.864 ∗ 4 ∗ 280 = 968 kips P0 = 1.27 ∗ 4 ∗ 280 = 1422 kips 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 1254 968 1422 Pn = 887 kips 58 Pu = 0.65 X 887 = 576.6 kips > 543 ππππ (ππ ππ) ∴ As = ρAg = 0.03 X 280 = 8.4 in2 Similarly Column ID: C3 Column size=15"X20" ∴ As = 9.00 in2 Column ID: C4 Column size=14"X14" ∴ As = 5.88 in2 Column ID: C5 Column size=12"X14" ∴ As = 5.04 in2 Column ID: C6 Column size=20"X20" ∴ As = 12 in2 Column ID: C7 Column size=22"X22" ∴ As = 14.52 in2 Column ID: C8 Column size=14"X18" ∴ As = 7.56 in2 59 Column ID: C9 Column size=12"X12" ∴ As = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) Column ID: C10 Column size=12"X14" ∴ As = 5.05 in2 Column ID: C11 Column size=14"X18" ∴ As = 7.56 in2 Column ID: C12 Column size=14"X14" ∴ As = 5.88 in2 60 7.3 For 5th storey column design Column ID: C1 Assume Column size=14"X14" Ag = 14 X 14 = 196 in2 ρ = 0.03 Pu = 209 kips MX = 614 kip-in My = 386 kip-in ex = MX 614 = = 2.938 in Pu 209 ey = My 386 = = 1.847 in Pu 209 ex = 0 γ= 14 − 5 = 0.64 14 ey 1.847 = = 0.132 h 14 Pnx0 = 0.89 ∗ 4 ∗ 196 = 697.76 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 2.938 = = 0.21 h 14 Pny0 = 0.7 ∗ 4 ∗ 196 = 549 kips P0 = 1.27 ∗ 4 ∗ 196 = 995.69 kips 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 697.76 549 995.69 Pn = 444 kips Pu = 0.65 X 444 = 288 kips > 285 ππππ (ππ ππ) 61 ∴ As = ρAg = 0.03 X 196 = 5.88 in2 Column ID: C2 Assume Column size=14"X18" Ag = 14 X 18 = 252 in2 ρ = 0.03 Pu = 404 kips MX = 1135 kip-in My = 460 kip-in ex = Mx 1135 = = 2.81 in Pu 404 ey = My 460 = = 1.14 in Pu 404 ex = 0 γ= 18 − 5 = 0.722 18 ey 1.14 = = 0.063 h 20 Pnx0 = 1.06 ∗ 4 ∗ 252 = 1073 kips ey = 0 γ= 14 − 5 = 0.64 14 ex 2.81 = = 0.2 h 14 Pny0 = 0.75 ∗ 4 ∗ 252 = 755 kips P0 = 1.27 ∗ 4 ∗ 252 = 1280 kips 1 1 1 1 1 1 1 = + − = + − Pn Pnx0 Pny0 P0 1073 755 1280 62 Pn = 677 kips Pu = 0.65 X 677 = 440 kips > 404 ππππ (ππ ππ) ∴ As = ρAg = 0.03 X 252 = 7.56 in2 Column ID: C3 Column size=14"X18" ∴ As = 7.56 in2 Column ID: C4 Column size=14"X14" ∴ As = 5.88 in2 Column ID: C5 Column size=12"X12" ∴ As = 4.32 in2 Column ID: C6 Column size=15"X15" ∴ As = 6.75 in2 Column ID: C7 Column size=15"X15" ∴ As = 6.75 in2 Column ID: C8 Column size=14"X16" ∴ As = 6.75 in2 63 Column ID: C9 Column size=12"X12" ∴ As = 4.32 in2 Column ID: C10 Column size=12"X12" ∴ As = 4.32 in2 Column ID: C11 Column size=12"X16" ∴ As = 5.75 in2 Column ID: C12 Column size=12"X12" ∴ As = 4.32 in2 (Note: The minimum column dimension to 12 inches. Bibliography No. 2) 64 Table 7.1 Column design summary with lateral load condition Column ID C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 Steel Area in in2 Column Size 1st Storey 14" X 14" 14" X 20" 15" X 20" 15" X 15" 14" X 16" 24" X 24" 24" X 24" 16" X 20" 12" X 12" 14" X 18" 14" X 20" 14" X 14" 3rd Storey 14" X 14" 14" X 20" 15" X 20" 14" X 14" 12" X 14" 20" X 20" 22" X 22" 14" X 18" 12" X 12" 12" X 14" 14" X 18" 14" X 14" 5th Storey 14" X 14" 14" X 18" 14" X 18" 14" X 14" 12" X 12" 15" X 15" 15" X 15" 14" X 16" 12" X 12" 12" X 12" 12" X 16" 12" X 12" 1st Storey 5.88 8.4 9 6.75 6.72 17.28 17.28 9.6 4.32 7.56 8.4 5.88 3rd Storey 5.88 8.4 9 5.88 5.04 12 14.52 7.56 4.32 5.04 7.56 5.88 5th Storey 5.88 7.56 7.56 5.88 4.32 6.75 6.75 6.72 4.32 4.32 5.76 4.32 65 CHAPTER VIII RESULTS & DISCUSSIONS 8.1 Results For beam: Without lateral load Positive Negative Steel Steel Total Total in in2 in in2 13.52 23.18 With lateral load Positive Steel Negative Total Steel Total in in2 in in2 15.62 32.67 For column: No of Storey 1st Storey 3rd Storey 5th Storey Without lateral load Total reinforcement of column in in2 77.28 58.56 54.96 With lateral load Total reinforcement of column in in2 107.07 91.08 70.14 8.2 Discussions From the results we can see that the amount of reinforcement varies in a significant amount while considering lateral loads and not considering lateral loads in the design. The concrete section also varies for both the condition. The inner beams carry more load than the perimeter beams. The inner columns carry more load than the other columns. The perimeter columns carry medium load than the inner columns. The corner columns carry smaller loads than other columns. οΆ For Beam design it is found that the amount of steel required in design while considering lateral loads are about 28% higher of the amount of steel required in design without considering lateral loads. οΆ In 1st storey columns design it is found that the amount of steel required in design while considering lateral loads are about 38% higher of the amount of steel required in design without considering lateral loads. οΆ In 3rd storey columns design it is found that the amount of steel required in design while considering lateral loads are about 55% higher of the amount of steel required in design 66 οΆ In 5th storey columns design it is found that the amount of steel required in design while considering lateral loads are about 27% higher of the amount of steel required in design without considering lateral loads. οΆ Average considering lateral loads are about 37% higher of the amount of steel required in design without considering lateral loads. 8.3 Comparison chart & data 8.3.1 Positive steel area (in2) comparison chart on beam Positive Steel Area (in2) Comparison on Beam 1.6 Without lateral load 1.4 With lateral load Steel Area 1.2 1 0.8 0.6 0.4 0.2 0 Beam ID B1 B2 B3 B4 B5 B6 B7 B8 B10 B11 Without lateral load 0.64 0.76 0.64 0.97 1.14 0.97 0.86 0.64 0.89 0.6 1.37 0.89 1.37 0.89 0.89 With lateral load 1.14 1.28 1.44 1.35 0.94 1.03 0.75 0.93 1.07 1.21 1.05 1.08 0.55 B9 1 B12 B13 B14 B15 0.8 67 8.3.2 Negative steel area (in2) comparison chart on beam Negative Steel Area (in2) Comparison Chart on Beam 3.5 Without lateral load 3 With lateral load Steel Area 2.5 2 1.5 1 0.5 Beam ID0 B1 B2 B3 B4 B5 B6 B7 1.7 1.5 Without lateral load 0.98 1.2 With lateral load 1.49 2.16 2.13 2.81 2.47 2.51 2.4 0.98 1.51 1.86 B8 B9 B10 B11 B12 B13 B14 B15 1.12 1.56 1.03 2.48 1.61 2.48 1.61 1.56 1.1 1 2.62 2.94 2.86 2.7 1.88 1.6 8.3.3 1st story comparison chart & data Steel area comparison between two case (1st Storey) 20 18 Without lateral load Steel Area 16 14 With lateral load 12 10 8 6 4 2 Column0ID C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 Without lateral load 4.32 6.48 6.48 4.32 5.76 12 12 5.76 4.32 5.76 5.76 4.32 With lateral load 8.4 9 6.75 6.72 9.6 4.32 7.56 8.4 5.88 5.88 17.28 17.28 68 8.3.4 3rd storey comparison chart & data Steel area comparison between two case (3rd Storey) 16 14 Without lateral load With lateral load Steel Area 12 10 8 6 4 2 0 Column ID C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 Without lateral load 4.32 4.32 4.32 4.32 4.32 7.68 7.68 4.32 4.32 4.32 4.32 4.32 With lateral load 8.4 9 5.88 5.04 12 14.52 7.56 4.32 5.04 7.56 5.88 5.88 8.3.5 5th storey comparison chart & data Steel area comparison between two case (5th Storey) 8 Without lateral load 7 With lateral load Steel Area 6 5 4 3 2 1 Column 0ID C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 Without lateral load 4.32 4.32 4.32 4.32 4.32 5.88 5.88 4.32 4.32 4.32 4.32 4.32 With lateral load 5.88 7.56 7.56 5.88 4.32 6.75 6.75 6.72 4.32 4.32 5.76 4.32 69 CHAPTER IX CONCLUSION & RECOMMENDATION 9.1 Conclusion The column section varies for different stories. Amount of reinforcement in column varies for different stories. The beam section does not vary significantly for different stories. Amount of reinforcement in beam varies for different stories. The cost is higher when lateral load is considered for design than that is not considered for design. Though the overall cost is higher but the design of building considering lateral load is more safe and reliable. 9.2 Recommendation The analysis can be compared for flat plate design. Dynamic analysis for earthquake loading was not considered in this study and hence should be considered in future study. The similar investigation can be made by providing shear wall or other type of lateral bracing system. 70 BIBLIOGRAPHY 1. ACI Code, 2002, 1995. 2. ACI 318 - 21.6.1.1 3. Arthur H. Nilson, (2005) Design of Concrete Structures (12th Edition), TATA McGraw-Hill Company Ltd, New Delhi. 4. Arthur H. Nilson, (2006) Design of Concrete Structures (13th Edition), TATA McGraw-Hill Company Ltd, New Delhi. 5. Bangladesh National Building Code BNBC-2006. Housing and building Research Institute. Darussalam, Mirpur, Dhaka 1218.and Bangladesh Standard and Testing Institution. 16/A Tejgaon Industrial Area, Dhaka1208. 6. Evangelos Petroutsos, (1998) Mastering Visual Basic 6, 1st Indian edition. 7. Everard Noel J. and Tanner John L. “Reinforced Concrete Design” McGraw-Hill, New York, USA, 1966. 8. Khan, A.F. Advanced Concrete Structures. Dhaka-1: Rizia Khatun 61, Hossani Dalan. 2002. 9. Leet Kenneth M. and Bernal Dionisio “Reinforced Concrete Design” 3 rd edition McGraw-Hill, Singapore, 1997. 10. Park and Pauley, Reinforced Concrete Structure, The McGraw-Hill Companies, Inc.International edition. 11. Refer to the table on page 6 from section 9 of the ACI 318. 12. S.N. Sinha, (1995) Handbook of Concrete Design, Tata McGraw-Hill Publishing Companies. 13. Vazirani, V.N. Concrete Structures. Delhi: Khanna Publishers 2-B, Nath Market, Nai Shrak, 1980. 71