Bhakta Bahadur Shrestha

Structural Analysis & Design Report

A STRUCTURAL DESIGN REPORT OF THE PROPOSED BUILDING OF RESIDENTIAL

OWNER: Mr. Bhakta Bahadur Shrestha

SUBMITTED TO: Dharan Sub-Metropolitan city, Sunsari

Structural Analysis & Design Report

TO WHOM IT MAY CONCERN This report comprises the summary of the residential building of Mr. Bhakta Bahadur Shrestha 15-Dharan Nepal. The reports consist of the design procedures adopted, the assumptions made, the inputs made in the design and the design output. During the design, it is assumed that the client will completely follow the architectural as well as the structural design. It is also assumed that the construction will be supervised by professional engineer.

The designer will not be responsible if any alterations to the structural system is made by the client or the contractor without the prior written permission from the designer, or the alterations to non-structural system is made such that the weight of each individual floor or the weight of the whole building is altered by more than 10% of design weight of each floor and the total weight.

The design calculations and derivations are limited to only a minimum to let the concerned people know the methodology adopted. However, the calculations may be provided to the client or concerned authorities when needed, upon request. Hence the building is safe.

1

Structural Analysis & Design Report

TABLE OF CONTENTS

S.N. Title 1

Introduction

Page No. 3

2

Salient features

3

3

Design Approach and Methodology

6

4

Preliminary Design

8

5

Final Analysis

9

6

Design Methodology

11

7

Analysis Output

13

8

Design of Members

20

2

Structural Analysis & Design Report

1.0 Background This report summarizes structural analysis and design of the Residential building for Dharan

Sub-Metro politician City. The analysis and design has been based on the

prevailing codes that are in practice in Nepal, the National Building Code of Nepal and the IS codes at places.

2.0 Salient Features 2.1 Project Information: Owner

:

Mr. Bhakta Bahadur Shrestha

Building Type

:

Residential Building

Location

:

Dharan-15

Plot no.

:

Land Area

:

Plinth Area

:

2.2 Building Features: Type of Structure:

RCC Framed Structure

Storey:

3-Storey + Staircase Cover

Storey Height:

3.048m

Total Height:

12.192 m

2.3 Site Condition: Soil Type:

III (for seismic consideration as per NBC 105)

Seismic Zone Factor:

1.0

Safe Bearing Capacity:

150 KN/m2 (assumed)

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Structural Analysis & Design Report

2.4 Material Specification: Considering Architectural, Economic and strength demands reinforced cement concrete (RCC) is used as the major structural material. The selected material also confirms the availability and ease in construction. The concrete grade used is M20 as per Indian Standard Specification. This material provides minimum grade of structural concrete and favorable for easy production and quality control as well. Fe 500 is provided as longitudinal and shear reinforcing in Beams, Columns, foundations, and slabs wherever RCC is used.

Considerations of material for loading and strength parameter are as detailed below:

Structural Components: Concrete: Grade:

M20

Characteristic Compressive Strength:

20 N/mm2

Unit Weight:

25.0 KN/m3

Young’s Modulus of Elasticity (E):

= 5000 √ fck N/mm2 ≈ 22360680 KN/m2 (for M20)

Steel Reinforcement: Grade:

Fe 500 (for both longitudinal and shear reinforcement)

Non-Structural Components: Brick wall: Unit Weight:

18.85 KN/m3

Strength:

Not Available

Finishing: Plaster: Unit Weight:

20.4 KN/m3

Flooring:

Screed + Punning

Unit Weight per meter:

1.2 KN/m2

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Structural Analysis & Design Report

2.5 Loading Details Number of Storey

1 Storey + Semi Basement + Staircase Cover

Loading in General

Structural Self Weight

(Gravity loads)

Live Load for residential services Dead load of finishing materials for floor

Panel walls

250mm & 125mm thick brick walls without openings 125mm thick brick walls with 30% openings

Partition walls

125mm thick (half brick) walls with 30 & 20% openings

Parapet walls

125 mm thick (half brick) wall height 0.8m

Live Load

As per IS 875 Part II

Lateral Loading

As per NBC 105:1994


The loads distributed over the area are imposed on area element and that distributed over length are imposed on line element whenever possible.
Where such facility is not feasible, equivalent conversion to different loading distribution is carried to load the Model near the real case as far as possible.
For lateral load, necessary calculations were performed and checked using NBC 105: 1994 for response spectrum method.
Different load combinations based on Nepal National Codes are developed and used for design purposes. Load Combinations: The load combinations are based on NBC 105: 1994 Static Load Combination: 1.5 DL + 1.5 LL Seismic Load Combinations: 1.0 DL + 1.3 LL± ± 1.25 EQ 0.9 DL ± 1.25 EQ For seismic loading, mass equivalent to the load that composed of 100% of Dead load and 25% of Live load is taken into consideration. The Earthquake lateral loads were used in the combination from the Self-Generated Load on the Seismic coefficient Method. Modal analysis is carried out using FEM Based three dimensional analyses. 5

Structural Analysis & Design Report

3.0 Design Approach and Methodology: 3.1 Introduction The structure is analyzed for full Finite Element. Beams and columns modeled as frame (line) elements with five and three internal stations. All floor slabs are modeled as Shell (Area) elements with sufficient and appropriate meshing. Modulus of elasticity and Poisson’s ratio for used material i.e. M20 grade concrete (as per Indian Specification) are taken accordingly and section properties used are based on Preliminary section sizing with consideration for deflection, minimum size specified and serviceability. Computation for stiffness as a whole is carried out using FEM based latest software. Full Modal Analysis is carried out up to twelve modes confirming more than 95 % seismic mass participation and it is applied for lateral seismic force distribution that generated with NBC 105 based Spectral Function for Soil Type-III. For Section Design and Check, suitable Load combinations as suggested in NBC105:1994 and if not covered in that, IS 1893- 2002 is referred with consideration of Envelopes of internal Forces developed. Foundation design is carried out to satisfy strength and stability requirements. 3.2 Software used: (Introduction to Analysis software) The analysis for the structural system was carried out using ETABS 2016 ver 16.0.0 is a product of computers and structures Inc, Berkeley. It is a FEM based software having facility of RC Design based on IS-456:2000

3.3 Structural Performance: Structural response under limit state of serviceability is thoroughly checked. The force and stiffness relationship resulting the deflection under various load cases and combined action of forces are duly evaluated. Basically short-term elastic deflection due to vertical loads and lateral deflection due to seismic forces are of major importance along with the long-term deflection of beam elements under sustained loading condition due to shrinkage and creep are also taken into account.

3.4 Deformation under Vertical Loads:

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Structural Analysis & Design Report

Maximum vertical deflection in all components that resulted under vertical load of combined effect of self, imposed dead and live load are checked for every element and maintained to be within permissible limit. Short-term elastic deflection and long-term deflection due to shrinkage and creep due to sustained loads also are maintained within permissible limits for all the elements.

3.5 Deformation under Lateral Loads: Effect of lateral load due to seismic force is analyzed using self-generated seismic load compatible with Codal provision. The distribution of lateral force at different parts of the structure is done based on the response under unit force. Using Complete Quadratic Combination (CQC) method of modal combination combines the deformations, and related forces reported.

3.6 Recommendations: The following recommendations are made: •

Materials used shall confirm minimum standard specified before use. Primarily the cement, aggregate, sand and steel shall be used that confirms to NS or IS standard.

•

Batching, mixing, placing and curing of concrete and steel fabrication and placing shall be done as per standard practice.

•

7

Construction safety shall be well planned and implemented.

Structural Analysis & Design Report

4.0 Preliminary Design The Preliminary Design was done using the prevailing thumb rules and span consideration. Slab: The slab is designed based on IS456:2000. The slab is designed to meet the deflection criteria for the slab. Beam: The beam is designed based on IS456:2000. The slab is preliminarily designed to meet the deflection criteria as well as the moment requirements for the span. Column: The column is preliminarily designed to meet the stiffness criteria for the building. Staircase: The staircase is designed to satisfy the moment requirement as well as the deflection criteria.

The sizes of the structural components are as given below: Sizes of Structural Components: Slab:

5” thick RCC (M20) Slab

Beam:

Rectangular Beams size-

Column:

Square, size-

Staircase:

Waist Slab 5” thick

8

10” X 15” (BXD)

12”X 12” (HXB)

Structural Analysis & Design Report

5.0 Final Analysis 5.1 Load Calculations: Refer Table: Load Intensity of Building Components Live Load:

2.0 KN/m2 (for all rooms)

Live Load:

3 KN/m2 (for staircases and lobbies)

Roof Live Load:

1.5 KN/m2 (for roof accessible), 0.75 KN/m2 (for roof inaccessible)

5.2 Seismic Lump Load: Seismic weight: Comprises Dead Load+ 25% of Live Load (as per IS Code for live load intensity ≤ 3 KN/m2) Seismic wt. at ith floor level (WI) = (Total dead load of all components i.e. Beam, Slab, Columns And Walls for ½ height above and ½ height below the floor level + 25% of live load) n

Total Weight of the frame, W= ∑ Wi

Where, n = total number of storey

I=1

Seismic Wt. of Building W = 2311.94 KN Base Shear Calculation: As Per NBC 105: Total Horizontal Base Shear V= Cd × W Where, Cd = C×Z×I×K Where, Basic Shear Factor (C)

= According to time period of vibration and Soil type

Seismic Zoning Factor (Z) = For Dharan Importance Factor (I)

= According to the type of building

Performance Factor (K)

= for the moment resisting frame

Distribution of design seismic force: Fi = Design Seismic Force at floor Level I Wi = seismic wt. at ith floor level hi = height of floor i measured from base According to NBC 105:1994 Height of building (h) = 12.192 m 9

Structural Analysis & Design Report

Soil type = III Time period (T) = 0.06 × H0.75 = 0.39 Sec C = 0.08

(from Fig 8.1 of NBC105:1994)

Z = 1.00

(for Dharan, Fig 8.2 of NBC105:1994)

I = 1.0

(for Residential Bldg., Table 8.1 of NBC105:1994)

K = 1.00

(for Ductile Moment resisting Frame, Table 8.2 of NBC105:1994)

Cd = C×Z×I×K = 0.08 Total Horizontal Base shear Vx = Vy = 0.08*2311.94 Total Horizontal Base shear Vx = Vy = 184.955 KN

5.3 Load Cases: Dead : Self Weight of the building structural components (Beams, columns and slabs) Finish : Weight of the finishing of the slabs as well as staircases (including steps). Wall

: Wall loads (inclusive of plaster)

Live

: Live load in the building area elements.

Rlive : Live load in the terraces both accessible and inaccessible (not including in seismic behaviour) EQX : Spectral Seismic Load in X – Direction EQY : Spectral Seismic Load in Y – Direction

5.4 Load Combination: DL = 1.5Dead + 1.5Finish + 1.5 Wall + 1.5 Rlive + 1.5Live DQX = 0.9 Dead + 0.9 Wall + 0.9 Finish ± 1.25 EQX DQY = 0.9 Dead + 0.9 Wall + 0.9 Finish ± 1.25 EQY DLEQX = 1.0 Dead + 1.0Wall + 1.0 Finish + 1.3 Live ± 1.25 EQX DLEQY= 1.0 Dead + 1.0 Wall + 1.0 Finish + 1.3 Live ± 1.25 EQY

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Structural Analysis & Design Report

6.0 Design of Structural Members 6.1 Design Assumptions: Foundation The Safe Bearing Capacity (SBC) of the soil is taken to be 150 KN/m2. The depth of the foundation is taken as 1.67 m. It is assumed that the soil below is converted to a firm base by sufficient compaction through any convenient means or as directed by the site engineer.

Beam: The beams are assumed to be rectangular. The preliminary design of the beam is carried out considering the deflection criteria as well as the loading condition.

Slab: The longest span slab is designed and for uniformity in construction, all the slabs are detailed according to the designed slab. The slab is designed based on IS 456:2000, for adjacent edge discontinuous. However during detailing, the torsion in the free edges is considered.

6.2 Design Methodology: The design of beams and columns that are the structural components in the building are carried out using the results and analysis for critical responses and also checking with manual calculations is carried out. The design of the foundation is carried out based on the base reactions as obtained from the software with necessary adjustments. The design of slabs and staircases are carried out based on the prevailing design practices, following the codal provisions.

6.2 Calculation of Wall Loads. The calculations of the loads are given in the following tables:

Load Intensity of Wall 10”Thickness of wall Full wall intensity =15.0 KN/M 11

Structural Analysis & Design Report

20% opening Wall intensity =12.0KN/M 30% opening Wall intensity =10.5KN/M

5”Thickness of wall Full wall intensity =7.50 KN/M 20% opening Wall intensity =6.0 KN/M 30% opening Wall intensity =5.2 KN/M Parapet 5”wall Parapet wall =2.2KN/M

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Structural Analysis & Design Report

7.0 ANALYSIS OUTPUT Result from Structural models and analysis

3D Model of the Building

13

Structural Analysis & Design Report

JOINT REACTIONS

14

Structural Analysis & Design Report

Design Plan (Basement)

15

Structural Analysis & Design Report

Design Plan (Ground Floor)

16

Structural Analysis & Design Report

Shear Force Diagram (Sample only)

17

Structural Analysis & Design Report

Axial Force Diagram (Sample only)

18

Structural Analysis & Design Report

Bending Moment Diagram (Sample only)

19

Structural Analysis & Design Report

8.0 Design of Members Design of Beams and Columns The design of beams and columns are done from the software itself. However, it is to be notified that the limitations of the design by the software have been evaluated and the adjustments have been made accordingly. The samples (summary) of the design through the software based on IS456: 2000 has been presented hereunder. Output for the Reinforcement Area (Beams and Columns)

Grid -1

20

Structural Analysis & Design Report

Grid –2

21

Structural Analysis & Design Report

Grid –3

22

Structural Analysis & Design Report

Grid –4

23

Structural Analysis & Design Report

Grid –A

24

Structural Analysis & Design Report

Grid –B

25

Structural Analysis & Design Report

Column Reinforcement First Floor Second Floor

Node No.

Column Type

Ground Floor

38,40

C-1 (12"X12")

8-16φ

4-16φ+4-12φ

4-16φ+4-12φ

_

29,30,31, 34,36

C-2 (12"X12")

4-20φ+4-16φ

8-16φ

4-16φ+4-12φ

8-12φ

32

C-3 (12"X12")

8-20φ

4-20φ+4-16φ

8-16φ

4-16φ+4-12φ

Grid No.

Beam Type

Y-dir

Stirrups

Beam Reinforcement Top Reinforcement Bottom Reinforcement 2-16φ (T) +2-16φ (E) 3-16φ (T) 2-16φ (T) +1-16φ (E) 3-16φ (T) 2-16φ (T) +1-12φ (E) 2-16φ +1-12φ (T) 3-12φ (T) 3-12φ (T) 2-16φ (T) +1-16φ (E) 2-16φ +1-12φ (T) 2-16φ (T) +1-12φ (E) 2-16φ +1-12φ (T) 3-12φ (T) 3-12φ (T) 3-12φ (T) 2-16φ +1-12φ (T)

Floor

GF 1st B-1 (10"X15") 2nd Top GF 1st B-2 (10"X15") 2nd 3rd

X-dir

Stair Cover

8mm φ @4" c/c near joint & 6" c/c at mid 8mm φ @4" c/c near joint & 6" c/c at mid 8mm φ @4" c/c near joint & 6" c/c at mid

Stirrups 8mm φ @4" c/c near joint & 6" c/c at mid 8mm φ @4" c/c near joint & 6" c/c at mid

Combined Footing Reinforcement Details Node No.

Footing Type

Size

Reinforcement in x-direction & ydirection

Concrete Footing Depth

Edge Depth

Footing depth from Ground level

31,32

CF2

6'0"X12'0"

12mm φ @ 150mm c/c

16"

8"

5'-6"

34,36

CF1

6'0"X12'0"

12mm φ @ 150mm c/c

16"

8"

5'-6"

Isolated Footing Reinforcement Details Node No.

Footing Type

30,40

F-1

Size

Reinforcement in x-direction & ydirection

Concrete Footing Depth

Edge Depth

Footing depth from Ground level

5'6"X5'6"

12mm φ @ 150mm c/c

16"

8"

5'-6"

Strap Footing Reinforcement Details

Node No.

Footing Type

Size

Reinforcement in xdirection & ydirection

31,34

F-1

5'6"X5'6"

12mm φ @ 150mm c/c

Type SB-1

26

Size 12"X18"

Concrete Footing Depth

Edge Depth

16"

8"

Strap Beam Reinforcement Details Top reinforcement Bottom Reinforcement 4-16mm φ Th. 3-16mm φ Th.

Footing depth from Ground level 5'-6"

Stirrups 2-L-8mm φ @4" c/c th.

Structural Analysis & Design Report

ETABS 2016 Concrete Frame Design IS 456:2000 Beam Section Design

Beam Element Details Type: Ductile Frame (Summary) Level

Element

Unique Name

Section ID

Combo ID

Station Loc

Length (mm)

LLRF

Story1

B10

10

Beam 10X15

DCon7

3200.4

3352.8

1

b (mm)

h (mm)

bf (mm)

ds (mm)

dct (mm)

dcb (mm)

254

381

254

0

25

25

Section Properties

Material Properties Ec (MPa)

fck (MPa)

Lt.Wt Factor (Unitless)

fy (MPa)

fys (MPa)

22360.68

20

1

500

500

Design Code Parameters ɣC

ɣS

1.5

1.15

Factored Forces and Moments Factored Mu3 kN-m

Factored Tu kN-m

Factored Vu2 kN

Factored Pu kN

-99.1431

5.885E-06

94.1851

0.3002

Design Moments, Mu3 & Mt Factored Moment kN-m

Factored Mt kN-m

Positive Moment kN-m

Negative Moment kN-m

-99.1431

8.654E-06

0

-99.1431

Design Moment and Flexural Reinforcement for Moment, Mu3 & Tu Design -Moment kN-m Top

(+2 Axis)

Design +Moment kN-m

-99.1431

Bottom (-2 Axis)

0

-Moment Rebar mm²

+Moment Rebar mm²

Minimum Rebar mm²

Required Rebar mm²

744

0

744

208

372

0

0

372

Shear Force and Reinforcement for Shear, Vu2 & Tu Shear Ve kN

27

Shear Vc kN

Shear Vs kN

Shear Vp kN

Rebar Asv /s mm²/m

Structural Analysis & Design Report

Shear Ve kN

Shear Vc kN

Shear Vs kN

Shear Vp kN

Rebar Asv /s mm²/m

123.3232

52.2367

71.0865

85.0373

553.33

Torsion Force and Torsion Reinforcement for Torsion, Tu & VU2 Tu kN-m

Vu kN

Core b1 mm

Core d1 mm

Rebar Asvt /s mm²/m

6.235E-06

86.4033

224

351

0

ETABS 2016 Concrete Frame Design IS 456:2000 Column Section Design

Column Element Details Type: Ductile Frame (Summary) Level

Element

Unique Name

Section ID

Combo ID

Station Loc

Length (mm)

LLRF

Story1

C4

50

Col 12X12

DCon7

0

3048

0.651

Section Properties b (mm)

h (mm)

dc (mm)

Cover (Torsion) (mm)

304.8

304.8

56

30

Material Properties Ec (MPa)

fck (MPa)

Lt.Wt Factor (Unitless)

fy (MPa)

fys (MPa)

22360.68

20

1

500

500

Design Code Parameters ɣC

ɣS

1.5

1.15

Axial Force and Biaxial Moment Design For Pu , Mu2 , Mu3 Design Pu kN

Design Mu2 kN-m

Design Mu3 kN-m

Minimum M2 kN-m

Minimum M3 kN-m

Rebar Area mm²

Rebar % %

712.789

-14.2558

73.8201

14.2558

14.2558

2175

2.34

Axial Force and Biaxial Moment Factors

28

K Factor Unitless

Length mm

Initial Moment kN-m

Additional Moment kN-m

Minimum Moment kN-m

Major Bend(M3)

0.714001

Minor Bend(M2)

0.665395

2667

29.528

0

14.2558

2667

-2.1788

0

14.2558

Structural Analysis & Design Report

Shear Design for Vu2 , Vu3 Shear Vu kN

Shear Vc kN

Shear Vs kN

Shear Vp kN

Rebar Asv /s mm²/m

Major, Vu2

56.7692

80.3933

30.3333

56.7692

337.85

Minor, Vu3

48.336

80.3933

30.3333

48.336

337.85

Joint Shear Check/Design Joint Shear Force kN

Shear VTop kN

Shear Vu,Tot kN

Shear Vc kN

Joint Area cm²

Shear Ratio Unitless

Major Shear, Vu2

N/A

N/A

N/A

N/A

N/A

N/A

Minor Shear, Vu3

N/A

N/A

N/A

N/A

N/A

N/A

(1.1) Beam/Column Capacity Ratio Major Ratio

Minor Ratio

N/A

N/A

Additional Moment Reduction Factor k (IS 39.7.1.1) Ag cm²

Asc cm²

Puz kN

Pb kN

Pu kN

k Unitless

929

21.7

1651.588

314.4795

712.789

0.702111

Additional Moment (IS 39.7.1) Consider Ma

Length Factor

Section Depth (mm)

KL/Depth Ratio

KL/Depth Limit

KL/Depth Exceeded

Ma Moment (kN-m)

Major Bending (M3 )

Yes

0.875

304.8

6.248

12

No

0

Minor Bending (M2 )

Yes

0.875

304.8

5.822

12

No

0

Notes: N/A: Not Applicable N/C: Not Calculated N/N: Not Needed

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Structural Analysis & Design Report

DESIGN OF FLOOR SLAB Design Data Dimensions of the slab (c/c distance b/w supports), Length of short span,

Lx

= 3.35 m

Length of long span,

Ly

= 3.96 m

Width of the supporting beam,

= 230

mm

Clear cover to main reinforcement

= 20

mm

Assume dia. of reinforcement steel

= 8

mm

fck

= 20

N/mm 2

fy

= 500

N/mm 2

Calculations d = 101

mm

lx = 3.35 m (or) 3.221 m whichever is less;

d = 3.221

m

ly = 3.96 m (or) 3.831 m whichever is less;

d = 3.831

m

Assume the thickness of slab as Effective span, (ly / lx ) =

125

mm ;

Effective depth,

1.19 < 2 ; Here, (ly / lx ) is less than 2, Hence design the slab as two way slab

Load Calculations Dead Load of slab

= 0.125 x 25

Finishes load on slab Live Load on slab

= 3.13 KN/m 2 = 1.20 KN/m 2 = 3.0 KN/m 2

Dust Load on slab

= 0

KN/m 2

Other load on slab

= 0

KN/m 2

Total Dead load acting on the Structure = 4.33 KN/m 2 Total live load acting on the Structure = 3.0 KN/m 2 2 Factored Design Load w = 11.00 KN/m (Type of panel according to support condition)

Support Condition

Two Adjacent Edges Discontinuous

For this support condition, 1.19,

Short span coefficient for (ly / lx ) =

Long span coefficient,

For negative moment,

ax =

0.0593

For negative moment,

ay =

0.047

For positive moment,

ax =

0.0445

For positive moment,

ay =

0.035

Moment Calculation Mx

Max. BM per unit width,

= ax w l x 2

Mu / bd2

Mu

2

pt

My

& Ast, req mm

0.50

0.1428

144

0.66

0.1904

192

N/mm

At mid span,

5.08

At supports,

6.77

For Short Span,

= (0.12/100) bD

Provide

Y 8

@

At mid span,

3.99

0.46

0.131

132

At supports,

5.36

0.62

0.1784

180

Provide

pro)

= 0.33

= 125

Refer Fig. 4 of IS 456, Modification factor

= 2

Allowable (Span / deff ) ratio

= 52

Effective depth required

= 62

mm

< d prov. Hence OK

Y 8

@

supports for long span

Check for Deflection fs = 0.58 fy (Ast req / Ast

150

mm 2

150 mm c/c at midspan & 335 mm 2 ) 150 mm c/c at midspan &

supports for short span

Percentage of tension reinforcement

=

Reinforcement details

For Long span,

30

Ast , min

2

%

KNm

= ay w l x 2

%

(Ast pro. =

(Ast pro. =

335 mm 2 )

Structural Analysis & Design Report

Design of Combined foundation Pleft(X)(unfactored) Pright(Y)(Unfactored) Soil bearing Cent Col Size Cornor Col Size Dist betw. Col. Center to center

361.33 488.00 150 0.3 0.3 3.35

KN KN KN/mm2 m m m

Max P Net upward soil pressure = Net upward soil pressure along length =

732 2 198.91 KN/m

Area req Width prov Total Length provided length Left Projection Right Projection

6.23 CG/from Left of Force 1.83 m 3.40 Check Value 3.5 m

0.00 0.75

0.15 0.15

1.92 4.4

364.00 KN/m

B.M under colm X= B.M under colm Y= dis dis

4.10 4.10 1.49 2.01

maxim projection 0.15

KN-m KN-m from left from right

Maximum hooging Moments

-322.22 KN-m

from left

Maximum hooging Moments max moments d calculated from moments =

-626.22 KN-m 4.10 KN-m 28.47 mm

from right

Check for two way shear D= d=

ok

550 494 mm

2.76543E-05 Ast

Ast at bottom

Ast mim.=

2

mm

12 dia spacing =

2

190.62

2.76543E-05 Ast

Ast At top Ast.

mm

2

108.43 mm

19.06

2

125 mm -1806.60 1806.60

-1 Ast

1907.18

12 dia spacing =

1084.82 mm provide spacing =

2

2

19.06 19.06 =0

-1 Ast

19.07

1084.824 mm

1907.18 mm

-3511.03

2

provide spacing =

125 mm

20

Grade of concrete M

Check for one way shear at d distance (Vu)= -179.82 Nominal shear stress(Tv)= -0.20 % of tension steel p = 12 dia 0.18 shear strength of M20 concrete for above % steel =

0.32 Ok

for 12 dia.

Check for two way shear concreate capacity =

1754132.72 N

From load =

606601.80 N

check

ok lateral distance

0.765

Transverse reinforcement 400 KN/m 117.05 KN-M

W= B.M = transverse reinforcement dis.(b)= 2 3.92914E-05 Ast Ast. Required 12 dia spacing =

31

556.86

1288

Ast min =

mm

544.67 544.67

-1 Ast mm 190.62 mm

2

763.5264 mm2

763.53 mm provide spacing=

2

125.00 mm for 12 dia.

Structural Analysis & Design Report

Design of Strap Footing

Project info: Strap Footing

Data:

Status of designe:

Exterior column load [KN].unfactored Interior column load [KN].unfactored Load factor Distance between column center lines[m] Depth of foundation Df [m] Allowable bearing capacity of soil [KN/sq.m] Width of ext. col. In strap beam direction [m] Width of ext. col. In direct perpendicular strap beam [m] Width of int. col. In strap beam direction [m] Width of int. col. In direct perpendicular strap beam [m] Breadth of strap beam [m] Eccentricity of exterior load from footing [m] R.C designation : Fcu [N/sq.mm] reinf. Strength : Fy [N/sq.mm] density of soil [KN/cu.m]

= = = = = = = = = = = = = =

TRUE

212 254.667 .

1 3.35 1.5 150 0.3 0.3 0.3 0.3 0.3 0.688 20 500 19

Calculation: reaction of ext.footing R1 geo. reaction of ext.footing R1T Req. ext. footing

266.79 [KN] 329.37 [KN] 2.20 [sq.m]

Dim. sq

1.48183

reaction of int.footing R2 geo. reaction of int.footing R2T Req. int. footing

199.87 [KN] 246.76 [KN] 1.65 [sq.m]

Dim. sq

1.2826

Use dimensions for ext.footing

L= B=

1.676 1.676

[m] Area prov.d 2.81 [m] in strap direction

128%

Use dimensions for int.footing

L= B=

1.676 1.676

[m] Area prov.d 2.81 [m] in strap direction

171%

check dim

Design of strap beam: Breadth of strap beam [m]

0.3 306.05 450 500

depth of strap beam from shear d Use depth d total depth H fcu

=

Width Depth

= = 2

K = M/bd fcu Z As bottom Design shear

= = = v=

Design concrete shear vc =

20 N/smm

300 mm 450 mm

fy

2

1.40 N/mm 2 0.56 N/mm

[mm] [mm] [mm]

TRUE = 500 N/smm

Max. B.M. Max. S.F.

2 0.12 N/mm 328.31 mm 2 600.00 mm

TRUE

A's required As required As provided

Mu‾ = 109 kNm Vu = 164 kN Mu = 42 kNm 2 mm 0.00 2 765.82 Top mm 2 800 Top mm

Diameter of stirrups 8 mm Spacing of stirrups reqd. 346 mm

check shear at col face

32

TRUE

As prvd. 104% No. legs

TRUE 2

Structural Analysis & Design Report

Design of exterior footing:

fcu

TRUE

147.48 [KN/sq.m]

Net presure under ext. footing

20 N/smm

fy

500 N/smm

Safe bearing capacity 150 [KN] [KN] Overburden height 1.0 Area of footing reqd. 1.90 [KN] [KN] Area of footing provided 2.81 500 [KN/sq.m] Footing thickness Short span Long span Length L= 1.68 Width B= 1.68 m 300.00 mm Column breadth 300 Column width Max. cantilever proj. 0.69 Max. cantilever proj. 1.38 m 139.62 kNm Max. B.M. /m width 35 Max. B.M. /m width

m mm m kNm

K = M/bd2fcu

N/mm 2

Ult. column load Self weight Overburden Total load Net upward pressure ult.

266.79 49.16 98.31 414.26 147.48

0.037 410.40 782.06 12 125

Z As required /m width Diameter of bars Spacing of bars As provided/m width

[KN/sq.m] m m2 m2

A prvd.

TRUE L reqd. 1.14 B/W 1.00

[mm]

As min 577

N/mm 2

K = M/bd2fcu

0.009

mm

Z As required /m width Diameter of bars Number of bars/side As provided/m width

12 [mm] As prvd. 125 [mm] 905 [sq.mm] 116%

[mm] [mm] [mm] 905 [sq.mm]

No. of bars 422 mm 13 190 [sq.mm] 13

TRUE

476%

0.00 [KN] Dist. to critical section 0.00 [N/sq.mm] Shear force 0.37 [N/sq.mm] Shear stress

Punch shear Punch shear stress Allow.shear stress

688 [mm] 101 [KN] 0.23 [N/sq.mm] TRUE

Design of interior footing:

fcu

20 N/smm

Ult. column load Self weight Overburden Total load Net upward pressure ult.

199.87478 44 103 347 124

Short span Width B= Column width Max. cantilever proj. Max. B.M. /m width 2

K = M/bd fcu Z As required /m width Diameter of bars Spacing of bars As provided/m width

fy

500 N/smm

Safe bearing capacity [KN] [KN] Overburden height [KN] Area of footing reqd. Area of footing provided [KN] [KN/sq.m] Footing thickness Long span

1.68 m

0.010 N/mm 363 mm 185 [mm]

150 1.1 1.60 2.81

[KN/sq.m] m 2 m 2 m

A prvd.

TRUE L reqd. 0.95 B/W 1.00

450 [mm]

Length L= 1.68 m Column breadth 300 mm Max. cantilever proj. 0.69 m Max. B.M. /m width 29 kNm

300 mm 0.69 m 29 kNm

12 125

TRUE

123.66 [KN/sq.m]

Net presure under int. footing

2

[mm] [mm] 905 [sq.mm]

2

N/mm

As min 512 2

K = M/bd fcu

0.009

Z As required /m width Diameter of bars Number of bars/side As provided/m width

12 [mm] 125 [mm] As prvd. 905 [sq.mm] 488%

No. of bars 374 mm 13 180 [sq.mm] 13

503% Punch shear Punch shear stress Allow.shear stress

33

0 [KN] Dist. to critical section 0.000 [N/sq.mm] Shear force 0.39 [N/sq.mm] Shear stress

344 [mm] 43 [KN] 0.11 [N/sq.mm] TRUE

TRUE

Structural Analysis & Design Report

DESIGN OF DOG LEGGED STAIRCASE Data Internal Dimensions Length = Width = Floor Height = Fck = Fy = Riser = Tread = Landing width = Effective Span = Height of each flight = No. of risers in each flight No. of Tread in each flight

3.9 1.93 3.05 20 500 166.75 250 1070 3.3 1.525 9.145427 8.145427

m m m N/mm2 N/mm2 mm mm mm m m Nos Nos

Design d

=

104

mm Required

D d

= =

125 104

mm mm

Loads DL of waist slab DL on horizontal area DL of steps LL FF Total load Factored load

= = = = = = =

3.125 3.76 2.084375 3 1.2 10.04 15.1

kN/m

= =

21 25

kN-m kN

d from BM consideration

86

mm

1.896 0.498 518

% mm2

= =

12 218

mm mm

Ast

=

125

mm

Dia of bar Spacing

= =

8 400

mm mm

2

kN/m2 kN/m2 kN/m2 kN/m2 kN/m2 (of one flight)

BM and SF Mu Vu

k pt Ast

= = =

Main Reinforcement Dia Spacing

Distribution Steel 2

Development Length Ld Therefore, Ld Provide, Ld

34

= = =

Ld = (Ø x σs) / (4 x Tbd) 1088 mm 1090 mm

Structural Analysis & Design Report

List of design code and Standards 1.

NBC-000-114:1994

: All relevant design codes in Nepal

2.

IS 456 – 2000

: Code for practice for plain & Reinforced concrete

3.

IS 875 – 1987

: Code of practice for Design Loads (other than Earthquake load for building & structures.

4.

IS 1893(part-I)-2002

: Code of practice for earthquake resist design of Structures.

5.

IS 13920 – 1993 Reinforced

: Code of practice for Ductile detailing of Concrete structures subjected to seismic forces.

6.

SP: 16 – 1980

: Design aids for Reinforced concrete to IS 456 -

1978

7.

35

ETABS 2016 V 16.0.0

: Proprietary program of Research Engineers

Structural Analysis & Design Report

36