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IJSRD - International Journal for Scientific Research & Development| Vol. 7, Issue 02, 2019 | ISSN (online): 2321-0613 Analysis, Design and Estimation of RC Shear Walls G Plus 13 Multi- Storied Residential Building 1 2 3 4 5 L Ravi Kumar K. V. Ganesh T Bhanu Prakash P Geetha Afjal Basha 1Associate Professor 2,3,4,5BE Student 1,2,3,4,5Department of Civil Engineering 1,2,3,4,5Kuppam Engineering, Ananatapur, A.P, India Abstract— Computer Aided “Analysis, design and estimation we require formwork of greater strength, which means the of RC Shear Walls G PLUS 13 Multi-Storied Residential conventional formwork, is not suitable for the construction. Building” involves analysis of building frames by using Hence we require an aluminum formwork which is called STAAD Pro. Conventional method of analysis involves lot of mivan shuttering. complications and tedious calculations such analysis is a time The proposed building is G+13 stories R.C.C framed consuming task. Analysis can be made quickly by using structure. The building consists of four flats in each floor and software’s. STAAD Pro is the leading design software in the the total flats in the building are 56 numbers. This project market. Many design companies use this software for their which is going on in Bangalore comprises of development of project design purposes. Hence this project mainly deals with residential Building along with other necessary utilities. This the analysis of the building by using STAAD Pro , drafting document pertains to the structural designs carried out for a by AutoCAD, Architecture design by REVIT architecture part of above said residential township project for various and Estimation done by the MS excel. structures. The development is in the seismic Zone – II. The Keywords: STAAD Pro, REVIT Architecture, RC Wall Load basic wind speed at location of the development is 33 m/s. SBC of soil according to soil investigations is 250 KN/m2. I. INTRODUCTION The design parameters considered are as per Indian Standard Day to day increase in the industrial growth and population Code of practice. established the problem of constructing number of buildings Block 3 Block 2 Block 1 either for the residence or for office or for industry. On Living room 5.1x3.20 6.5x4.7 5.5x3.3 account of the high cost involved in acquiring land especially Bed room 1 4.1x3.2 4.5x3.7 3.9x3.3 in densely populated areas, there is invariably a need for the Bed room 2 4.4x3.2 3.7x3.2 4.0x3.2 construction of multi-storied buildings. So, the advanced Bed room 3 4.5x4.2 knowledge in technology especially knowledge in reinforced Dining/kitchen 4.1x3.2 4.2x2.7 5.6x3.2 cement concrete has come to the rescue of the engineer for Bathroom 1 1.8x1.4 2.4x1.2 2.1x1.5 planning and designing multi-storied buildings. The stage has Bathroom 2 2.3x1.2 2.5x1.2 2.3x1.5 come in which multi-storied construction is essential and Shaft 1 1.2x0.7 3.1x1.5 1.5x0.7 inevitable. Shaft 2 3.2x0.9 In this project, the concept of monolithic Utility 3.2x1.0 2.0x1.2 3.2x1.2 construction technology is adapted. That means the whole structure along with the slab is casted at a single pour [at a Balcony 2.0x1.2 3.3x1.2 time]. In order to construct a monolithic structure obviously Table 1: Dimensions of the rooms Fig. 1: Building layout All rights reserved by www.ijsrd.com 1551 Analysis, Design and Estimation of RC Shear Walls G Plus 13 Multi-Storied Residential Building (IJSRD/Vol. 7/Issue 02/2019/427) II. LITERATURE REVIEW E. A Study on Construction of RC Shear Walls for Multi- Storied Residential Building-by A. Shiva Shankar, S. Sunil A. IS: 875 (Part 1) for Dead Loads: Prathap Reddy Indian Standard Code of Practice For Design Loads (Other A study has been carried out to determine the strength of RC Than Earthquake) For Buildings and Structures. The dead shear wall of a multistoried building by changing shear wall load comprises of the weights of walls, partitions floor location. Three different cases of shear wall position for a finishes, false ceilings, false floors and the other permanent multi-story building have been analyzed. Incorporation of constructions in the buildings. The dead loads may be shear wall has become inevitable in multi-store building to calculated from the dimensions of various members and their resist lateral forces unit weights. The unit weights of plain concrete and III. ANALYSIS AND DESIGN reinforced concrete made with sand and gravel or crushed natural stone aggregate may be taken as 24 KN/m3 and 25 A G+13 floor residential building is considered whose 3 KN/m respectively. architectural plan and structural framing plans were prepared B. IS: 875 (Part 2) for Imposed Loads: as shown in figure below, before it is modeled in STAAD Pro. Indian Standard Code Of Practice For Design Loads (Other The entire analysis of building has been done in one stage Than Earthquake), For Buildings And Structures, Imposed keeping the IS code provision in view wherever necessary. load is produced by the intended use or occupancy of a The whole building has been split into its structural building including the weight of movable partitions, components viz., slab, beams, columns and footings. distributed and concentrated loads, load due to impact and A. Statement of the Project vibration and dust loads. Imposed loads do not include loads The design data shall be as follows: due to wind, seismic activity, snow, and loads imposed due 2 Live load : 3.0 kN/m to temperature changes to which the structure will be Floor finish : 1.0 kN/m2 subjected to, creep and shrinkage of the structure, the Location : Bangalore (Zone -II) differential settlements to which the structure may undergo. Depth of foundation below ground: 3.25 m C. IS: 875 (Part 3) for Wind Loads: Safe bearing capacity (SBC) of the soil: 250 kN/m2 Indian Standard Code Of Practice For Design Loads (Other Ground floor and first floor height : 3.8 m Than Earthquake) For Buildings And Structures, This First floor to fourteenth Floor Height: 2.825m standard gives wind forces and their effects (static and Floors : G + 13 floors. dynamic ) that should that taken into account when designing Inner and exterior Wall: 150 mm thick reinforced concrete buildings, structures and components thereof. Wind is air in walls motion relative to the surface of the earth. 1) Material Properties Concrete: All components unless specified in design: M25 grade all The primary cause of wind is traced to earth’s 2) Material Properties Steel: rotation and differences in terrestrial radiation. The effects are HYSD reinforcement of grade Fe 415 confirming to IS: 1786 primarily responsible for convection either upwards or is used throughout. downwards. The wind generally blows horizontal to the ground at high wind speeds. Since vertical components of B. Load Combinations: atmospheric motion are relatively small the term ‘Wind’ Dead load + Live load denotes almost exclusively the horizontal wind, vertical Dead load + live load + seismic load winds are always identified as such. The wind speeds are Dead load + live load + wind load assessed with the aid of anemometers or anemographs which Dead load + wind load are installed at meteorological observatories at heights Dead load + seismic load generally varying from 10 to 30 meters above ground. Live load + wind load D. IS: 1893 (Part 1) for Earthquake Resistant Design of Partial safety factor for loads: 1.5 Structures: Partial safety factor for steel: 1.15 Indian Standard Criteria for Earthquake Resistant Design of Partial safety Factor for Concrete: 1.5 Structures, (Part 1-General Provisions and Buildings), It deals 1) Dead Load with assessment of seismic loads on various structures and Dead load consists of the permanent construction material earthquake resistant design of buildings. Its basic provisions load compressing the roof, floor, wall, and foundation are applicable to buildings; elevated structures; industrial and systems, including claddings, finishes and fixed equipment. stack like structures; bridges; concrete masonry and earth Dead load is the total load of all the components of the dams; embankments and retaining walls and other structures. building (or) structure. Temporary elements such as scaffolding, temporary Weight = volume x density Slab weight = 0.15x25 = 3.75 kN/m2 excavations need not be designed for earthquake forces. 2 Self-weight of Floor finishing = 0.01x25 = 0.25 kN/m All rights reserved by www.ijsrd.com 1552 Analysis, Design and Estimation of RC Shear Walls G Plus 13 Multi-Storied Residential Building (IJSRD/Vol. 7/Issue 02/2019/427) k1 = risk coefficient k2 = terrain roughness and height factor k3 = topography factor k4 = Importance factor for cyclonic region. Basic wind speed in Bangalore 33 m/s Fig. 2: Dead load 2) Live load Live loads are produced by the use and occupancy of a building. Load includes those from human occupants, furnishings, no fixed equipment, storage, and construction and maintenance activities. In STAAD we assign live load in Fig. 4: wind load terms of UDL. We have to create a load case at live load and 4) RC Wall Load select all the beams to carry such load. After the assignment Floor load is calculated based on the load on the RC WALL. of the live load the structure appears as shown below. Assignment of floor load is done by creating load case for RC Live load is taken as 3 kN/m2 WALL load. After the assignment of RC WALL load of a structure look as shown in below. The intensity of RC WALL load is taken as 3 .75 kN/m2 Fig. 3: live load 3) Wind Load Fig. 5: shear wall load In the list of loads we can see wind load is present both in vertical and horizontals loads. This is because wind causes IV. MANUAL DESIGN OF REINFORCED STRUCTURES uplift of the roof by creating a negative pressure on the top of the roof. Wind produces non static loads on a structure at A. Design of Beam: highly variable magnitudes. The variation in pressure at Beam is the horizontal member of a structure, carrying different locations on a building is complex to the point that transverse loads. Beams are rectangular in cross-section. pressure may become too analytically intensive for precise Beam carries the floor slab or the roof slab. Beam transfer all consideration in design. the loads including its self –weight to the columns or walls. a) Design Wind Pressure: Beam is subjected to bending moments and shear forces. It can be mathematically expressed as follows It is typically used for resisting vertical loads, shear forces Vz = Vb x k1x k2 x k3 x k4 {Pg.no 5 clause no 6.3 of IS 875- and bending moments. 2015} Types of Beams pz = 0.6Vz2 {Pg.no 9 clause no 7.2 of IS 875-2015} 1) Simply supported beam pd = Kd x Ka x Kc x pz {Pg.no 9 clause no 7.2 of IS 875- 2) Fixed beam 2015} 3) Cantilever beam 0.7 pz {Pg.no 9 clause no 7.2 of IS 875-2015} 4) Continuous beam Design Wind Pressure is Maximum of ( pd , 0.7pz) 5) Overhanging beam Where Vb = design wind speed at height Z in m/s {Pg.no 51 6) We are considering the fixed beam. Annexure A of IS 875 Part3-2015} All rights reserved by www.ijsrd.com 1553 Analysis, Design and Estimation of RC Shear Walls G Plus 13 Multi-Storied Residential Building (IJSRD/Vol. 7/Issue 02/2019/427) 1) Details of Beam Materials: Length available beyond the actual cutoff point from center For M25 Concrete, Fck = 25 N/mm2 of supports 2 l 4 For Fe 415 Steel, fy = 415 N/mm eff 1.85 1.850.15m 2 2 Clear span l = 7.4 m Effective length leff = 7.26+0.23 = 7.49m Provision of shear reinforcement D = 600 mm w l 73.24 Vu = u eff Mu = 361.73 KN-m 2 2 Moment of Resistance X max = 146.4KN Xumax u 2 Design shear force at distance d = 412 face to support at a Mu,lim 0.36 10.42 bd fck distance of d d l support width = eff dCentre of beam 2 2 d = 520mm 4 0.23 D = 600mm = 0.412 2 2 Assuming ϕ 20 for main reinforcement and ϕ8for shear = 1.47m reinforcement From similarity of triangle 146.42 Vu = 1.873= 137.10 KN 4 D 2D Breath of the beam between and V 137.10103 u 3 3 c bd 230412 B = 450 mm 2 Hence provide b = 450 mm = 0.426N/mm Tensile reinforcement (Ast) % Ps = 1002314.1= 0.66% A f 230412 st y Mu 0.87fy Ast d 1 bdfck = 0.42 c D = 412mm = (412+20+8) = 440mm Ast = 2004.79 mm2 At the upper lever of bars does not continue up to the critical Curtailment and detailing of reinforcement section for shear force. V=0.87fyAsvd=0.87415100412 16 ϕ of 8 bars S S 1.78103 A f v st y Mu 0.87fy Astd 1 =8356.269mm bdf ck Sv, min = 0.75×d = 0.75×412 = 309mm (or) Sv, min = 300mm Mu = 308.98106N-mm Sv, min given by the following formula Asv 0.4 Let theoretical cut off section from support=x bS 0.87f vmin y 100 0.4 Mu = 230S 0.87415 X = 1.00 vmin Sv min 1000.87415 2300.4 = Sv min =300mm from center of the beam Provide 2-Legged stirrups ϕ8 @ 300mm c/c Actually upper bars will be curtailed at 2.745+ (12 ϕ or d (or) Check shear strength at cut off point as per Cl 26.2.3.2(a) whichever greater) from Centre of the beam Shear at cut off point = = 2.745+0.412 W l l = u ef ef = 3.157 w 1.85 2 u 2 The curtailment of upper bars will be done at 3.157 m from Centre of the beam =73.24 4 73.2 1.85 φσ LD = st 2 2 4τ bd = 135.4KN 200.87415 = Shear strength of the section with ϕ8 @300mmc/c stirrups 41.61.2 2 = τ bdV = 0.940 < 2.02m 3 c us All rights reserved by www.ijsrd.com 1554
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