design of six storied residential apartment building

PRESIDENCY UNIVERSITY

Azimur Rahman School of Engineering

Department of Civil Engineering

Capstone Design

CE- 492 & 493

“Design of Six Storied Residential Apartment Building”

As Partial Fulfillment for Degree of B.Sc. in Civil

Engineering

This Capstone Design is Prepared By

Supervised By

Prof. Dr. Engr. Zahid Hossain Prodhan

Professor

Department of Civil Engineering

Presidency University, Bangladesh

121 033 045

121 035 045

121 037 045

121 120 045

Md. Jasim Uddin

Md. Nazmul Hasan

Md. Moinur Rahman Abir

Saifullah

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Declaration

The dissertation entitled “Design of Six Storied Residential Building” has been

performed under the supervision of Prof. Dr. Engr. Zahid Hossain Prodhan,

Professor, Department of Civil Engineering, Presidency University, Dhaka,

Bangladesh and approved in partial fulfillment of the requirement for the Bachelor

of Science in Civil Engineering. To the best of our knowledge and belief, the

capstone contains no materials previously published or written by another person

except where due reference is made in the capstone itself.

Name of the reviewerProf. Dr. Engr. Zahid Hossain Prodhan

ProfessorDepartment of Civil Engineering

Presidency University, Bangladesh

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Acknowledgement

We would like to express our special thanks of gratitude to our cordial teacher Prof. Dr. Engr. Zahid Hossain Prodhan who gave us the golden opportunity to do

this wonderful project on the topic “Design of Six Storied Residential Building” which also helped us in doing a lot of research and we came to know about so many new things we are really thankful to him.

Secondly, we would also like to thank the Department of Civil Engineering, PU

for helping us a lot in finalizing this project within the limited time frame.

Authors

Presidency University, 2016

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Table of Contents

Chapter 01

Project Overview .............................................................................................................................1

Chapter 02

Structural Design Criteria & Consideration ....................................................................................6

Chapter 03

Architectural Drawings ..................................................................................................................14

Chapter 04

Slab Design ....................................................................................................................................21

Chapter 05

Beam Design ..................................................................................................................................28

Chapter 06

Column Design ..............................................................................................................................37

Chapter 07

Foundation Design .........................................................................................................................47

Chapter 08

Stair Design ....................................................................................................................................56

Chapter 09

Underground Water Reservoir .......................................................................................................62

Chapter 10

Overhead Water Tank Design........................................................................................................67

Chapter 11

Septic Tank Design ........................................................................................................................70

Chapter 12

Appendix........................................................................................................................................72

References......................................................................................................................................84

Chapter 01

Project Overviews

Page 1

1.1 Capstone

The Capstone Project is a two-semester process in which students pursue independent research on a

question or problem of their choice, engage with the scholarly debates in the relevant disciplines, and -

with the guidance of a faculty mentor - produce a substantial paper that reflects a deep understanding of

the topic.

1.2 Concrete Slab

A concrete slab is common structural element of modern buildings. Horizontal slabs of steel reinforced

concrete, typically between 4 and 20 inches (100 and 500 millimeters) thick, are most often used to

construct floors and ceilings, while thinner slabs are also used for exterior paving. Sometimes these

thinner slabs, ranging from 2 inches (51 mm) to 6 inches (150 mm) thick, are called mud slabs,

particularly when used under the main floor slabs or in crawl spaces.

1.3 Beam

A beam is a structural element that is capable of withstanding load primarily by resisting against bending.

The bending force induced into the material of the beam as a result of the external loads, own weight,

span and external reactions to these loads is called a bending moment. Beams are characterized by their

profile (shape of cross-section), their length, and their material.

1.4 Column

A column or pillar in architecture and structural engineering is a structural element that transmits, through

compression, the weight of the structure above to other structural elements below. In other words, a

column is a compression member. The term column applies especially to a large round support (the shaft

of the column) with a capital and a base or pedestal and made of stone, or appearing to be so. A small

wooden or metal support is typically called a post, and supports with a rectangular or other non-round

section are usually called piers. For the purpose of wind or earthquake engineering, columns may be

designed to resist lateral forces. Other compression members are often termed "columns" because of the

similar stress conditions. Columns are frequently used to support beams or arches on which the upper

parts of walls or ceilings rest. In architecture, "column" refers to such a structural element that also has

certain proportional and decorative features. A column might also be a decorative element not needed for

structural purposes; many columns are "engaged", that is to say form part of a wall.

1.5 Foundation

A foundation (or, more commonly, foundations) is the element of an architectural structure which

connects it to the ground, and transfers loads from the structure to the ground. Foundations are

generally

considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (Geotechnical engineering) in the design of foundation elements of structures.

Project Overviews Chapter 01

Page 2

A stairway, staircase, stairwell, flight of stairs, or simply stairs is a construction designed to bridge a large vertical distance by dividing it into smaller vertical distances, called steps. Stairs may be straight, round, or may consist of two or more straight pieces connected at angles. Special types of stairs include

escalators and ladders. Some alternatives to stairs are elevators (lifts in British English), stair lifts and inclined moving walkways as well as stationary inclined sidewalks (pavements in British English).

1.7 Structural loads

Structural loads or actions are forces, deformations, or accelerations applied to a structure or its

components. Loads cause stresses, deformations, and displacements in structures. Assessment of their

effects is carried out by the methods of structural analysis. Excess load or overloading may cause

structural failure, and hence such possibility should be either considered in the design or strictly

controlled. Mechanical structures, such as aircraft, satellites, rockets, space stations, ships, and

submarines, have their own particular structural loads and actions. Engineers often evaluate structural

loads based upon published regulations, contracts, or specifications. Accepted technical standards are

used for acceptance testing and inspection. Various load names are given bellow:

Dead load

Live load

Wind loads

Snow, rain and ice loads

Seismic loads

Temperature changes leading to thermal expansion cause thermal loads

Ponding loads

Frost heaving

Lateral pressure of soil, groundwater or bulk materials

Loads from fluids or floods

Permafrost melting

Dust loads

Foundation settlement or displacement

Fire

Corrosion

Explosion

Creep or shrinkage

Impact from vehicles or machinery vibration

Construction loads

1.8 Masonry

Masonry is the building of structures from individual units laid in and bound together by mortar; the term

masonry can also refer to the units themselves. The common materials of masonry construction are brick,

building stone such as marble, granite, travertine, and limestone, cast stone, concrete block, glass block,

and cob. Masonry is generally a highly durable form of construction. However, the materials used, the

quality of the mortar and workmanship, and the pattern in which the units are assembled can significantly

Project Overviews

1.6 Stairs

Chapter 01

Page 3

affect the durability of the overall masonry construction. A person who constructs masonry is called a

mason or bricklayer.

1.9 Admixture

A material other than water, aggregates, or cement that is used as an ingredient of concrete or mortar to

control setting and early hardening, workability, or to provide additional cementing properties. Over

decades, attempts have been made to obtain concrete with certain desired characteristics such as high

compressive strength, high workability, and high performance and durability parameters to meet the

requirement of complexity of modern structures. The properties commonly modified are the heat of

hydration, accelerate or retard setting time, workability, water reduction, dispersion and air-entrainment,

impermeability and durability factors. Types of admixtures are given bellow:

Chemical admixtures - Accelerators, Retarders, Water-reducing agents, Super plasticizers, Air

entraining agents etc.

Mineral admixtures - Fly-ash Blast-furnace slag, Silica fume and Rice Husk Ash etc.

1.10 Welding

Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by

causing fusion, which is distinct from lower temperature metal-joining techniques such as brazing and

soldering, which do not melt the base metal. Some of the best known welding methods include:

Shielded metal arc welding (SMAW) – also known as "stick welding or electric welding", uses an

electrode that has flux around it to protect the weld puddle. The electrode holder holds the

electrode as it slowly melts away. Slag protects the weld puddle from atmospheric contamination.

Gas tungsten arc welding (GTAW) – also known as TIG (tungsten, inert gas), uses a non-

consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric

contamination by an inert shielding gas such as argon or helium.

Gas metal arc welding (GMAW) – commonly termed MIG (metal, inert gas), uses a wire feeding

gun that feeds wire at an adjustable speed and flows an argon-based shielding gas or a mix of

argon and carbon dioxide (CO2) over the weld puddle to protect it from atmospheric

contamination.

Flux-cored arc welding (FCAW) – almost identical to MIG welding except it uses a special

tubular wire filled with flux; it can be used with or without shielding gas, depending on the filler.

Submerged arc welding (SAW) – uses an automatically fed consumable electrode and a blanket

of granular fusible flux. The molten weld and the arc zone are protected from atmospheric

contamination by being "submerged" under the flux blanket.

Electroslag welding (ESW) – a highly productive, single pass welding process for thicker

materials between 1 inch (25 mm) and 12 inches (300 mm) in a vertical or close to vertical

position.


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1.11 Load combination in ETABS for analysis:

WSD

USD

UDCON3

UDCON4

UDCON5

UDCON6

UDCON15

UDCON16

UDCON17

UDCON18

DL+LL

1.4DL+1.7LL

0.75(1.4DL+1.7LL+1.7WX)

0.75(1.4DL+1.7LL-1.7WX)

0.75(1.4DL+1.7LL+1.7WY)

0.75(1.4DL+1.7LL-1.7WY)

1.05DL+1.275LL+1.4025EQX

1.05DL+1.275LL-1.4025EQX

1.05DL+1.275LL+1.4025EQY

1.05DL+1.275LL-1.4025EQY


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1.12 Grid details in ETABS analysis

Chapter 02

Structural Design

Criteria &

Consideration

Page 6

2.1 General

USD Design method used according to Bangladesh National Code (BNBC-2006), UBC-1994 and ACI-2008.

If any specifications or structure requirements not mentioned in the drawings or in the note sheet, follow BNBC-2006.

Any details not shown in the drawing should be done according to ACI-2008 Basic wind speed: 210 km/hr (for Dhaka) Seismic zone: 2 (for Dhaka) Other loads as per BNBC-2006.

2.2 Foundation

Existing Ground Level (EGL), Parking level and Finished ground level (FGL) are assumed to be at level of 0’-0’’, 2’-0’’ and 3’-0’’ respectively.

Depth of foundation is as per structural drawing and it should be measure from EGL.

Three inch (3’’) cement concrete (CC) must cast before casting foundation. This CC is not included in the depth of foundation.

2.3 Concrete

Concrete mix proportion and 28 days crushing strength of concrete cylinders

are as follows: Mix. proportion Crushing strength (f’c)

Column 1 : 1.5 : 3 35000 psi All other RCC 1 : 2 : 4 3000 psi

These crushing strength of concrete cylinders are based on Cylinder test of 150mm diameter and 300mm height.

Curing of RCC works: a. Curing time: minimum 14 days b. Method of crushing:

i. By pounding of water in case of horizontal surface ii. By wrapping other surfaces with just fabric and spaying water

frequency 2.4 Cement

Ordinary Portland cement confirming to BDS 2332: 1974/ASTM C150

Structural Design Criteria & Consideration Chapter 02

Page 7

2.5 Aggregate

Sylhet sand having minimum F.M. 2.5 shall be used as fine aggregates of RCC ¾’’ downgraded jhama brick chips shall be used in all RCC except columns,

beams and foundation. ¾’’ downgraded crushed stone shall be used for columns, beams and foundation.

2.6 Water

Fresh water should be used in concrete mixture.

2.7 Reinforcing Steels for Concrete Reinforcing steels designated by “T” shall be deformed billet steel bars having

yield strength, fy= 60 ksi and by “R” shall be deformed billet steel bars having yield strength, fy =40 ksi

2.8 Lap Length Lap length of splicing bars shall be as follows:

Bar size (mm) Tension bars Compression bars Column bars T 32 4’-6’’ 4’-3’’ 4’-3’’ T 25 4’-3’’ 3’-3’’ 3’-6’’ T 22 3’-4’’ 2’-9’’ 3’-0’’ T 20 2’-6’’ 2’-0’’ 2’-3’’ T 16 1’-9’’ 1’-9’’ 1’-9’’ T 12 1’-4’’ 1’-4’’ T 10 1’-0’’ 1’-0’’

2.9 Lap Location

1. Lap of column bars shall be made at mid height between floor slab or beam.

Not more than 50% of total bars in a column shall lapped in one location 2. Lap should not be provided at middle third zone of the span in case of beam

bottom bars, whereas it can be provided for Beam top bars 3. Lap splices, where provided, should be confined by hoops with maximum

spacing of d/4 (d= effective depth of beam) or 4’’ which is the minimum

Figure 2.1 Lap Splice for Beam


Page 8

Figure 2.2: Lap Splice for Column

2.10 Curtailment of Column Bars

If needed, column bars should cut at a minimum height of 3’-6’’ above the floor level which is concerned for the curtailment

2.11 Hooks of Rebar

90 degree (L- bent) standard hooks shall be provided for all reinforcing bars if not shown in the drawing

For beams, the end of the hooks shall be extend at last 4’’ beyond the main reinforcement as shown below:

For columns, the hooks in column ties shall be bent 45 degree inwards for at least 4’’ length as shown below:

Figure 2.3 Hook Rebar for Beam and Column


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2.12 Spacer Bars

To support second layer bars in beams, use 20mm diameter spacer bars @ 4’-0’’ c/c

2.13 Chairs

Use chairs of necessary dimension made of 12mm/16mm diameter bar to support top bars of mat foundation @ 4’-0’’ c/c

2.14 Corner Reinforcement

Corner reinforcement for beam supported 2-way slabs is shown below:

Figure 2.4: Corner Reinforcement

2.15 Clear Spacing of Rebar

Unless shown otherwise on plan, minimum clear space between beam rebar layers shall be 1’’ and between columns rebar layers shall be 1.5’’

2.16 Binder Rod

T10 binders wherever required shall be placed @ 10’’ c/c

Use T10 binder for top bars @ 12’’ c/c at places other than cantilever end. For cantilever end, see the detail as shown below:

Figure 2.5: Binder Rod


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2.17 Concrete Clear Cover for Reinforcing Bars

Figure 2.6: Clear Cover for Reinforcements

2.18 Reinforcement details for Slab Openings

Figure 2.7: Reinforcement details for Slab Opening


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2.19 Casting

Columns shall be cast in two lifts up to the bottom of the beam (or Drop/capital). At basement, the columns and retaining wall shall be cast together monolithically. There shall be a minimum of seven days gap between the two lifts. Capital, drop, floor slab and beams shall be cast together monolithically. Mechanical/electrical vibrators shall be used to compact concrete in footing, columns, beams and walls. Slabs may be compact manually

2.20 Water Stopper

10’’ wide PVC water stopper should be used at all construction joints below ground in mat, retaining wall and water tank wall

2.21 Position Stirrups/Ties Joint

Figure 2.8: Stirrup position and Tie joints


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2.22 Confinement Requirements of Beams & Columns at Joints for Earthquake Loading

Figure 2.9: Confinement requirements of Beams & Columns at Joints for Earthquake


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Chapter 03

Architectural

Drawings

Page 14

Architectural Plan & Elevation Chapter 03

3.1 Typical Floor Plan

Page 15


3.2 Ground Floor Plan

Page 16


3.4 Elevation

Page 17


Page 18


Page 19


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Chapter 04

Slab Design

Page 21

4.1 Calculation of slab thickness:

Thickness formula:

So, thickness of slab = 5”

4.2 Calculation of loads on slab:

Design load = 1.4DL + 1.7LL

4.3 Calculation for moment (moment co-efficient method):

fy f'c

60000 psi 3000 psi

one way simple supported one end continuous both end continuous cantilever

l/20 l/24 l/28 l/10

two way [l*{0.8+(fy/200000)}]/(36+9β)

or

perimeter/180

slab panel lb,ft la,ft β=lb/la slab type t,ft t,in rounded t,in

s1 16.75 11.25 1.49 two way 0.31 3.73 4

s2 16.75 15.58 1.08 " 0.36 4.31 5

s3 16.5 11.25 1.47 " 0.31 3.70 4

s4 17.75 15.58 1.14 " 0.37 4.44 5

s5 5.83 5 1.17 " 0.12 1.44 2

s6 16.92 15.58 1.09 " 0.36 4.33 5

thickness = 5"

slab panel self weight, psf pw, psf ff, psf total dl, psf LL, psf 1.4DL 1.7LL total load, psf

s1 62.5 50 25 137.5 40 192.5 68 260.5

s2 62.5 50 25 137.5 40 192.5 68 260.5

s3 62.5 50 25 137.5 40 192.5 68 260.5

s4 62.5 50 25 137.5 40 192.5 68 260.5

s5 62.5 50 25 137.5 40 192.5 68 260.5

s6 62.5 50 25 137.5 40 192.5 68 260.5

slab panel lb la m=la/lb case co-effi for neg moment co-effi of dl pos moment co-effi of ll pos monents

Ca neg Cb neg Ca pos, dl Cb pos,dl Ca pos,ll Cb pos,ll

s1 16.75 11.25 0.67 4 0.0834 0.0166 0.0484 0.0098 0.06 0.0122

s2 16.75 15.58 0.93 4 0.057 0.043 0.0312 0.0232 0.0366 0.0278

s3 16.5 11.25 0.68 8 0.0704 0.027 0.0416 0.0102 0.056 0.0128

s4 16.5 15.58 0.94 8 0.038 0.056 0.022 0.021 0.031 0.027

s5 5.83 5 0.86 4 0.0648 0.0352 0.0354 0.0196 0.0422 0.0236

s6 16.92 15.58 0.92 4 0.058 0.042 0.0318 0.0228 0.0374 0.0272

Slab Design Chapter 04

Page 22

Load on slab, W = 260.5 Moment, M = C*W*l2

4.4 Calculation of rebar spacing (for continuous end):

slab panel Ma neg Mb neg Ma pos dl Ma pos ll total Ma pos Mb pos dl Mb pos ll total Mb pos

lb-ft lb-ft lb-ft lb-ft lb-ft lb-ft lb-ft lb-ft

s1 3113.82 1373.91 1807.06 2240.16 4047.22 811.11 1009.74 1820.85

s2 4081.61 3558.94 2234.15 2620.82 4854.97 1920.17 2300.89 4221.06

s3 2628.45 2168.47 1553.18 2090.81 3643.99 819.20 1028.02 1847.22

s4 2721.08 4497.57 1575.36 2219.82 3795.18 1686.59 2168.47 3855.06

s5 477.90 352.94 261.08 311.23 572.30 196.52 236.63 433.15

s6 4153.22 3547.09 2277.11 2678.11 4955.22 1925.56 2297.16 4222.72

slab plan moment used bar e.depth, short e.depth,long Rn ρ As As,min spacing, c/c max spacing direction

lb-ft in in sq. in sq. in in 2h or 18"

s1 3113.82 #3 4.1 205.82 0.00358118 0.18 0.11 7.49 10.00 short, neg

1373.91 #3 3.69 112.12 0.00191158 0.08 0.11 12.00 10.00 long, neg

4047.22 #3 4.1 267.51 0.00472074 0.23 0.11 5.68 10.00 short, pos

1820.85 #3 3.69 148.59 0.00255313 0.11 0.11 11.68 10.00 long, pos

s2 4081.61 #3 4.1 269.79 0.0047634 0.23 0.11 5.63 10.00 short, neg

3558.94 #3 3.69 290.42 0.00515267 0.23 0.11 5.79 10.00 long, neg

4854.97 #3 4.1 320.90 0.00573542 0.28 0.11 4.68 10.00 short, pos

4221.06 #3 3.69 344.45 0.00619189 0.27 0.11 4.81 10.00 long, pos

s3 2628.45 #3 4.1 173.74 0.00300159 0.15 0.11 8.94 10.00 short, neg

2168.47 #3 3.69 176.95 0.00305933 0.14 0.11 9.74 10.00 long, neg

3643.99 #3 4.1 240.86 0.00422429 0.21 0.11 6.35 10.00 short, pos

1847.22 #3 3.69 150.74 0.0025913 0.11 0.11 11.50 10.00 long, pos

s4 2721.08 #3 4.1 179.86 0.00311154 0.15 0.11 8.62 10.00 short, neg

4497.57 #3 3.69 367.01 0.00663479 0.29 0.11 4.49 10.00 long, neg

3795.18 #3 4.1 250.85 0.00440968 0.22 0.11 6.08 10.00 short, pos

3855.06 #3 3.69 314.58 0.00561382 0.25 0.11 5.31 10.00 long, pos

s5 477.90 #3 4.1 31.59 0.00052977 0.03 0.11 12.00 10.00 short, neg

352.94 #3 3.69 28.80 0.00048276 0.02 0.11 12.00 10.00 long, neg

572.30 #3 4.1 37.83 0.00063521 0.03 0.11 12.00 10.00 short, pos

433.15 #3 3.69 35.35 0.00059325 0.03 0.11 12.00 10.00 long, pos

s6 4153.22 #3 4.1 274.52 0.00485234 0.24 0.11 5.53 10.00 short, neg

3547.09 #3 3.69 289.45 0.00513434 0.23 0.11 5.81 10.00 long, neg

4955.22 #3 4.1 327.53 0.00586331 0.29 0.11 4.58 10.00 short, pos

4222.72 #3 3.69 344.59 0.00619454 0.27 0.11 4.81 10.00 long, pos


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4.5 Sample calculation:

Moment, M = 3113.82 lb-ft [Ma (neg) = short direction]

Using steel bar = #3

Effective depth, d (short) = 5" − 0.75” −3

8⁄ ”

2= 4.1”

Effective depth, d (long) = 5" − 0.75” −3

8−

38⁄ ”

2= 3.69”

𝑅𝑛 =𝑀𝑢

∅𝑏𝑑2=

3113.82 ∗ 12

0.9 ∗ 12 ∗ 4.12= 205.82

𝜌 = 0.85 ∗3

60∗ (1 − √1 −

2 ∗ 205.82

0.85 ∗ 3000) = 0.00358

𝐴𝑠 = 𝜌𝑏𝑑 = 0.358 ∗ 12 ∗ 4.1 = 0.18 𝑖𝑛2

As (min) = 0.0018bh = 0.0018*12*5 = 0.11 in2 < As

So, As = 0.18 in2

Spacing = (0.11/0.18) *12 = 7.59 ≈ 7.5” c/c

So, provide #[email protected]” c/c


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Abir

Rectangle


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Abir

Rectangle


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Abir

Rectangle

Chapter 05

Beam Design

Page 28

ETABS Concrete Design

ETABS v9.7.4 - File:Etabs_Capstone - Kip-in Units

ACI 318-99 BEAM SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope) Level : STORY2 L=135.000 Element : B13 D=12.000 B=10.000 bf=10.000 Section ID : FB12X10 ds=0.000 dct=1.200 dcb=1.200 E=3122.000 fc=3.000 Lt.Wt. Fac.=1.000 fy=60.000 fys=60.000 Phi(Bending): 0.900 Phi(Shear): 0.850 Phi(Torsion): 0.850

Flexural Reinforcement for Major Axis Moment ------- End-I --------- --------- Middle -------- --------- End-J --------- Rebar Area Rebar % Rebar Area Rebar % Rebar Area Rebar % 1.497 1.248 0.573 0.477 1.549 1.291 Top (+2 Axis) 1.304 1.087 0.649 0.541 1.318 1.098 Bot (-2 Axis)

Design Mu Station Loc Design Mu Station Loc Design Mu Station Loc -730.724 7.500 -313.243 40.000 -750.793 129.000 Top (+2 Axis) 652.583 7.500 351.764 40.000 658.242 129.000 Bot (-2 Axis)

Controlling Combo Controlling Combo Controlling Combo UDCON18 UDCON18 UDCON17 Top (+2 Axis) UDCON17 UDCON17 UDCON18 Bot (-2 Axis)

Shear Reinforcement for Major Shear (V2) ------- End-I --------- --------- Middle -------- --------- End-J --------- Rebar Av/s Rebar Av/s Rebar Av/s 0.010 0.008 0.009

Design Vu Station Loc Design Vu Station Loc Design Vu Station Loc 15.465 7.500 14.223 90.000 15.166 129.000

Controlling Combo Controlling Combo Controlling Combo UDCON18 UDCON18 UDCON18

Torsion Reinforcement ------- Shear --------- ------ Longitudinal ----- Rebar At/s Rebar Al 0.000 0.000

Design Tu Station Loc Design Tu Station Loc 5.186 40.000 5.186 40.000

Controlling Combo Controlling Combo UDCON15 UDCON15

Beam Design Chapter 05

Page 29

Abir

Typewriter

Floor Beam

5.1 Check (FB):

5.1.1 T-beam check:

Beam L/4 (X-direction) 𝑏𝑤 + 2(8𝑡) C/C spacing of beam

FB 11’3”/4=33.75” 12+2*8*5=92” 35” +99” =134”

Minimum value, b=33.75”

Let, a = 1, As =0.85𝑓′𝑐∗𝑎𝑏

𝑓𝑦

= (0.85*3000*1*33.75)/60000

= 1.43 in2

Now, 𝑎 =𝐴𝑠𝑓𝑦

0.85∗𝑓′𝑐∗𝑏

= 1.43∗60000

0.85∗3000∗33.75

= 0.996 ≈1; a < t (so this beam is not a T-beam)

5.1.2 Moment capacity check:

𝑎 =(𝐴′𝑠 − 𝐴𝑠)𝑓𝑦

0.85𝑓′𝑐𝑏

=(2 ∗ 0.31 + 1 ∗ 1.00 − 3 ∗ 0.44) ∗ 60

0.85 ∗ 3 ∗ 10

= 0.71

∅ = 0.9 [from ETABS]

∅𝑀𝑛 = ∅(𝐴′𝑆 − 𝐴𝑠)𝑓𝑦 (𝑑 −𝑎

2) + ∅𝐴′𝑠𝑓𝑦(𝑑 − 𝑑′)

= 0.9 ∗ (2 ∗ 0.31 + 1 ∗ 1.00 − 3 ∗ 0.44) ∗ 60 ∗ (10.5 −0.71

2) + 0.9 ∗ 1.62 ∗ 60 ∗ (10.5 − 1.5)

= 951.67 kip − in > 750.793 kip − in [ETABS] ∴ 𝐬𝐞𝐜𝐭𝐢𝐨𝐧 𝐢𝐬 𝐨𝐤


Page 30

5.1.3 Stirrup check:

Vu = 15.47 kip [ETABS]

∅𝑣𝑐 = ∅2√𝑓′𝑐 ∗ 𝑏𝑑

= 0.85 ∗ 2 ∗ √3000*10*10.5

= 9776.85 lb

= 9.78 kip

𝑣𝑠 =𝑣𝑢 − ∅𝑣𝑐

∅

=15.47 − 9.78

0.85

= 6.69 kip

So, ∅𝑣𝑐 > 𝑣𝑠; no stirrup need, but we give minimum stirrup #3@5"c/c


Page 31

Fig: FB rebar layout (12”x10”) [End]

Fig: FB rebar layout (12”x10”) [Mid]

Reinforcement detailing of FB (12”x10”)


Page 32



ACI 318-99 BEAM SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope) Level : GF L=135.000 Element : B25 D=12.000 B=12.000 bf=12.000 Section ID : GB12X12 ds=0.000 dct=2.000 dcb=2.000 E=3122.000 fc=3.000 Lt.Wt. Fac.=1.000 fy=60.000 fys=60.000 Phi(Bending): 0.900 Phi(Shear): 0.850 Phi(Torsion): 0.850

Flexural Reinforcement for Major Axis Moment ------- End-I --------- --------- Middle -------- --------- End-J --------- Rebar Area Rebar % Rebar Area Rebar % Rebar Area Rebar % 1.400 0.972 0.400 0.278 1.363 0.946 Top (+2 Axis) 1.103 0.766 0.492 0.341 1.135 0.788 Bot (-2 Axis)

Design Mu Station Loc Design Mu Station Loc Design Mu Station Loc -652.346 6.000 -179.326 90.000 -637.535 129.000 Top (+2 Axis) 531.254 6.000 252.676 90.000 544.568 129.000 Bot (-2 Axis)

Controlling Combo Controlling Combo Controlling Combo UDCON17 UDCON18 UDCON18 Top (+2 Axis) UDCON18 UDCON17 UDCON17 Bot (-2 Axis)

Shear Reinforcement for Major Shear (V2) ------- End-I --------- --------- Middle -------- --------- End-J --------- Rebar Av/s Rebar Av/s Rebar Av/s 0.010 0.010 0.010

Design Vu Station Loc Design Vu Station Loc Design Vu Station Loc 12.882 22.500 12.280 90.000 13.733 129.000

Controlling Combo Controlling Combo Controlling Combo UDCON18 UDCON18 UDCON18

Torsion Reinforcement ------- Shear --------- ------ Longitudinal ----- Rebar At/s Rebar Al 0.000 0.000

Design Tu Station Loc Design Tu Station Loc 4.570 45.000 4.570 45.000

Controlling Combo Controlling Combo UDCON4 UDCON4


Page 33

Abir

Typewriter

Grade Beam

5.2 Check (GB):

5.2.1 T-beam check:

Beam L/4 (X-direction) 𝑏𝑤 + 2(8𝑡) C/C spacing of beam

FB 11’3”/4=33.75” 12+2*8*5=92” 35” +72.5” =107.5”

Minimum value, b=33.75”

Let, a = 1, As =0.85𝑓′𝑐∗𝑎𝑏

𝑓𝑦

= (0.85*3000*1*33.75)/60000

= 1.43 in2

Now, 𝑎 =𝐴𝑠𝑓𝑦

0.85∗𝑓′𝑐∗𝑏

= 1.43∗60000

0.85∗3000∗33.75

= 0.996 ≈1; a < t (so this beam is not a T-beam)



0.85𝑓′𝑐𝑏

=(3 ∗ 0.60 − 3 ∗ 0.44) ∗ 60

0.85 ∗ 3 ∗ 12

= 0.94



2) + ∅𝐴′𝑠𝑓𝑦(𝑑 − 𝑑′)

= 0.9 ∗ (3 ∗ 0.60 − 3 ∗ 0.44) ∗ 60 ∗ (10 −0.94

2) + 0.9 ∗ 1.80 ∗ 60 ∗ (10 − 1.5)

= 1073.22 kip − in > 652.35 kip − in [ETABS] ∴ 𝐬𝐞𝐜𝐭𝐢𝐨𝐧 𝐢𝐬 𝐨𝐤


Page 34



∅𝑣𝑐 = ∅2√𝑓′𝑐 ∗ 𝑏𝑑

= 0.85 ∗ 2 ∗ √3000*12*10

= 11173.54 lb

= 11.17 kip


∅

=12.88 − 11.17

0.85

= 2.01 kip

So, ∅𝑣𝑐 > 𝑣𝑠; no stirrup need, but we give minimum stirrup #3@5"c/c


Page 35

Reinforcement detailing &

section of GB (12”x12”)


Page 36

Chapter 06

Column Design

Page 37



ACI 318-99 COLUMN SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope) Level : GF L=96.000 Element : C1 B=12.000 D=12.000 dc=1.800 Section ID : C12X12 E=3122.000 fc=3.000 Lt.Wt. Fac.=1.000 fy=60.000 fys=60.000 RLLF=1.000 Phi(Compression-Spiral): 0.750 Phi(Compression-Tied): 0.700 Phi(Tension): 0.900 Phi(Bending): 0.900 Phi(Shear/Torsion): 0.850

Axial Force & Biaxial Moment Reinforcement for Pu-Mu2-Mu3 Interaction Column End Rebar Area Rebar % Top 1.440 1.000 Bottom 2.244 1.559

Column End Design Pu Design Mu2 Design Mu3 Station Loc Controlling Combo Top -0.276 52.876 33.191 84.000 UDCON18 Bottom 1.095 -436.986 -33.898 0.000 UDCON4

Shear Reinforcement for Major Shear (V2) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.000 4.227 84.000 UDCON16 Bottom 0.000 4.227 0.000 UDCON16

Shear Reinforcement for Minor Shear (V3) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.010 6.096 84.000 UDCON4 Bottom 0.010 6.096 0.000 UDCON4 Joint Shear Check/Design Joint Shear Shear Shear Joint Controlling Ratio VuTot phi*Vc Area Combo Major(V2) 0.516 41.495 80.449 144.000 UDCON15 Minor(V3) 0.750 60.304 80.449 144.000 UDCON15

C1-12x12

Column Design Chapter 06

Page 38





Column End Design Pu Design Mu2 Design Mu3 Station Loc Controlling Combo Top 1.585 29.700 -41.758 84.000 UDCON18 Bottom -20.771 29.718 1006.851 0.000 UDCON15



C2-12x18


Page 39





Column End Design Pu Design Mu2 Design Mu3 Station Loc Controlling Combo Top 177.495 186.370 -28.807 84.000 UDCON18 Bottom 102.786 1198.199 117.176 0.000 UDCON17



C3-15x18


Page 40

6.1 Design of Column (Sample:C3-15x18)

6.1.1 Design data

Design load (ETABS) = 177.5 kip

Moment in X direction, MUXO = 117.18 kip-in

Moment in Y direction, MUYO = 1198.2 kip-in

b = 15”, h = 18”

Compressive strength of concrete, f’c = 3000 psi

Tensile strength of steel, fy = 60000 psi

Elastic modulus = 29000000 psi

Assume, 𝜌 =𝐴𝑠𝑡

𝐴𝑔= 0.02 [1% to 8% steel of gross area]

6.1.2 Steel area calculation

Ag = 15*18 = 270 in2

Ast = Ag* ρ = 270*0.02 = 5.4 in2

Using 6#9 (1.00 in2) which Ast = 6 in2

Revised ρ = 6/270 = 0.022

As = A’s = Ast/2 = 6/2 = 2 in2

6.1.3 Tie bar design

Use #3 as tie

Spacing = 16*main bar dia. = 16*0.875 = 14 in.

Spacing = 48*tie bar dia. = 48*0.375 = 18 in. not to exceed the smallest value

Spacing = least dimension of colm = 15 in.

So, provide #3@14” c/c

6.1.4 Check for nominal aggregate size

Distance between to steel bar = 18"−2∗2−0.875∗4

3 = 3.5” (1<3.5<6) OK

[18” is the depth of column, 2” is clear cover, 0.875

is the dia. of #7, 3 is number of interval of steel]


Page 41

6.1.5 Column interaction diagram

P-M Points (X or 3-3 Direction) *

Loads

(kip)

-323.92

-209.03

-121.7

-63.02

-6.98

87.95

150.24

210.22

Moment

(kip-ft)

76.68

116.7

142.15

161.75

169.05

152.81

143.43

125.32

Loads

(kip)

297.34 372.06 439.06 497.39 537.22 537.22 537.22

Moment

(kip-ft)

125.32 106.85 86.64 65.36 47.62 12.37 0.00

P-M Graph (X or 3-3 Direction) *

Load-Moment Interaction ( X Direction)

Column Design

* Analysis Result from CSiCol V9.0.0

Chapter 06

Page 42

P-M Points (Y or 2-2 Direction) *

Loads

(kip)

-323.92 -150.24 -58.54 4.61 63.23 154.33 204.39 250.85

Moment

(kip-ft)

24.26 89.72 142.72 176.97 202.65 215.82 193.00 180.01

Loads

(kip)

329.67 398.59 461.19 517.26 537.22 537.22 537.22

Moment

(kip-ft)

161.91 142.23 119.80 94.99 84.08 27.21 0.00

P-M Graph (Y or 2-2 Direction) *

Load-Moment Interaction (Y Direction)

Column Design

* Analysis Result from CSiCol V9.0.0

Chapter 06

Page 43

6.1.6 Biaxial Bending Check

(Bresler’s reciprocal load method)

1

𝑃𝑛=

1

𝑃𝑛𝑥𝑜+

1

𝑃𝑛𝑦𝑜−

1

𝑃0

Pn = approximate value of ultimate load

Pnxo = ultimate load when ey=0

Pnyo = ultimate load when ex=0

P0 = ultimate load for concentrically loaded column

Here,

Cx = 15-2*2 = 11”

Cy = 18-2*2 = 14”

H = 18”

Ɣ = Cx/h = 11/18 = 0.61

Ɣ = Cy/h = 14/18 = 0.78

Ag = 270 sq. in.

Pg = Ast/Ag = 5.4/270 = 0.02

ex = Muyo/Pu = 1198.2/177.5 = 6.75

ex/h = 6.75/18 = 0.375 = tan a; a = 20.56o

∅𝑃𝑛𝑥𝑜

𝑓′𝑐𝐴𝑔

=537.22

18= 29.85

=> ∅𝑃𝑛𝑥𝑜 = 𝑓′𝑐𝐴𝑔 ∗ 29.85 = 3 ∗ 270 ∗ 29.85 = 24174.9

ey = Muxo/Pu = 117.18/177.5 = 0.66

ey/h = 0.66/18 = 0.04 = tan a; a = 2.1o

∅𝑃𝑛𝑦𝑜

𝑓′𝑐𝐴𝑔

=537.22

18= 29.85

=> ∅𝑃𝑛𝑦𝑜 = 𝑓′𝑐𝐴𝑔 ∗ 29.85 = 3 ∗ 270 ∗ 29.85 = 24174.9

1

∅𝑃𝑛=

1

24174.9+

1

24174.9−

1

177.5

∅𝑃𝑛 = −180.15 > 𝑃𝑢 OK


Page 44


Page 45


Page 46

Chapter 07

Foundation Design

Page 47

DL= 99.33 Kip

LL=15.77 Kip

Total vertical load = 115 Kip

Bearing capacity of soil, BC = 2.5 Ksf

∴ Required footing area = 115

2.5 = 46 ft2

So we use 7’×7’ square footing.

Upward pressure = 115

49 = 2.34 Ksf

Depth of footing (assume),d = 2× √A

= 2× √49 ≅ 15”

Critical perimeter,𝑏𝑜 = 2×{(15+15)+(18+15)}

= 126 inch

7.1.1 Punching shear check:

𝑉𝑈 = 2.34×{ 72 − ( (30×33)

12)}

= 98.57 kips

Now, ∅𝑉𝐶 = ∅ 4 √𝑓𝑐′ 𝑏𝑜𝑑

= 0.75× 4√(3000) × 126 × 15

= 310558.69

= 310.56 kips

Hence, ∅𝑉𝐶 > 𝑉𝑈 (Ok)

7.1.2 Check for beam shear:

𝑉𝑓, Flexural shear at a distance of 19.5” from the

face of column,

𝑉𝑓= 19.512⁄ × 2.34 × 7

= 26.62 kips

Allowable flexural shear, ∅𝑉𝐶 = ∅ 2 √𝑓𝑐′ 𝑏 𝑑

= 2× 0.75 × √(3000) × (7 × 12) × 15

= 103519.56 lb.

= 103.52 kips

Hence, ∅𝑉𝐶 > 𝑉𝑓 (Ok)

7.1.3 Moment:

𝑀𝑈= 2.34× 7 × 2.88 ×2.88

2× 12

= 815.17 kip-in

𝑅𝑢 = 𝑀𝑈

∅ 𝑏 𝑑2

= 815.17

0.9 × (7×12) × 152 = 0.048

7.1.4 Check for depth:

𝑅𝑢 = 𝑀𝑈

∅ 𝑏 𝑑2

⇒ 0.048 = 815.17

0.9 × (7×12) × 𝑑2

⇒ 𝑑2 = 224.64

⇒ 𝑑 = 14.987 in < 15 in (ok)

7.1.5 Now calculation for steel:

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×0.048

0.85×3)] 7 ×12× 15

= 1.39 𝑖𝑛2

7.1.6 Check for minimum reinforcement:

𝐴𝑠 𝑚𝑖𝑛 = 3 √𝑓𝑐

′

𝑓𝑦 × 𝑏𝑑

= 3 √3000

60000 × (7 × 12) × 15

= 3.45 𝑖𝑛2

7.1 Design of single footing (sample: F3)

Footing Design Chapter 07

Page 48

But not less than, 200

𝑓𝑦 bd =

200

60000 × 7 × 12 × 15

= 4.2 𝑖𝑛2 (govern)

Bar required = 4.2

0.44 = 10

Bar spacing = 8.4 in c/c

7.1.7 Development bar:

For #6 𝑏𝑎𝑟

𝑙𝑑 = 𝑓𝑦∝𝛽𝜆

25√𝑓𝑐′ × 𝑑𝑏

= 60000×1×1×0.8

25√(3000) × 0.44 = 16 in

Thickness of footing, T = 15+2+2 = 19 in


Page 49

7.2 Design of combine footing F4

Bearing capacity of soil = 2.5 ksf

Maximum axial load on footing 106.58 kip and 106.89 kip

Area of footing = ( 106.58+106.89 )

2.5

= 90 sft

So providing 7.5’× 12′ combined footing which area is 90 sft

Now cg of column load

X= 106.89×5.83

106.58+106.89 = 2.1

Figure: Final footing size


Page 50

Total upward pressure, 𝑞𝑢= 106.58+105.89+21.35

90 (Adding 10% of total load for safety)

= 2.61 ksf

Fig: SFD and BMD (diagram in kip)


Page 51

Assume depth of footing = 2√𝐴 = 2 × √90 = 18.97 ≅ 20"

7.2.1 Flexural or beam shear check

Critical section occurs at distance d=20” from the left face of column.

𝑉𝑢 = 77.54− (20

12) 𝜏 × 19.58 = 44.91 𝑘𝑖𝑝

Allowable flexural shear, ∅𝑉𝐶 = ∅ 2 √𝑓𝑐′ 𝑏 𝑑

= 2× 0.75 × √(3000) × (7.5 × 12) × 20

= 147880 lb.

= 147.88 kip

Hence, ∅𝑉𝐶 > 𝑉𝑓 (Ok)

Critical perimeter,𝑏𝑜 = 2×{(12+18)+(15+18)}

= 140 inch

7.2.2 Punching shear check:

𝑉𝑈 = {(6.43× 7.5) ×2.61} − { 2.61 × ( (32×38)

144)}

= 101.22 kips

Now, ∅𝑉𝐶 = ∅ 4 √𝑓𝑐′ 𝑏𝑜𝑑

= 0.75× 4√(3000) × 140 × 20

= 460 kip

Hence, ∅𝑉𝐶 > 𝑉𝑈 (Ok)

d= 20” (ok)

7.2.3 Design for positive moment

𝑀𝑈= + 91.78 k-ft. =91.78

7.5 = 12.24 k-ft. /ft.

𝑅𝑢 = 𝑀𝑈

∅ 𝑏 𝑑2

= 12.24×12×1000

0.9 × (7.5×12) × 202 = 34

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd


Page 52

= 0.85 3

60 [1−√(1 −

2×34

0.85×3)] ×12× 15

= 0.135 𝑖𝑛2


𝑓𝑦 bd =

200

60000 × 12 × 20 = 0.8 𝑖𝑛2 (govern)

Bar spacing = 0.44

0.8× 12 = 6.6 ≅ 6.5 𝑖𝑛 𝑐/𝑐(#6) in both directions.

7.2.4 Design for negative moment

𝑀𝑈= − 49.34 k-ft. =49.34

7.5 = 6.58 k-ft. /ft.

𝑅𝑢 = 𝑀𝑈

∅ 𝑏 𝑑2

= 6.58×12×1000

0.9 × (7.5×12) × 202 = 18.28

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×18.28

0.85×3)] ×12× 15

= 0.073 𝑖𝑛2


𝑓𝑦 bd =

200

60000 × 12 × 20 = 0.8 𝑖𝑛2 (govern)

Bar spacing = 0.44


7.2.5 Design for transverse beam

For column (12x18)

Assume steel spread over width= column width + 2× (𝑑

2)

= 12+2× (20

2)

= 32” = 2.67’

Net upward load = 106.58/7.5

= 14.21 k/ft.

Moment at face, 𝑀𝑈 = (14.21× 3′) × 3/2


Page 53

= 63.54 k-ft.

= 63.54/2.67 = 23.8 k-ft.

𝑅𝑢 = 𝑀𝑈

∅ 𝑏 𝑑2

= 23.8×12×1000

0.9 × 12 × 202 = 66.1

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×66.1

0.85×3)] ×12× 15

= 0.27 𝑖𝑛2


𝑓𝑦 bd =

200

60000 × 12 × 20 = 0.8 𝑖𝑛2 (govern)

Bar spacing = 0.44


Same as another transverse beam.

Fig: Plan view of combined footing


Page 54

Fig: Longitudinal section of footing

Fig: Footing Layout


Page 55

Chapter 08

Stair Design

Page 56


ACI 318-99 BEAM SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope)

Level : STORY2 L=135.000 Element : B29 D=12.000 B=10.000 bf=10.000 Section ID : SB12X10 ds=0.000 dct=1.200 dcb=1.200

E=3122.000 fc=3.000 Lt.Wt. Fac.=1.000 fy=60.000 fys=60.000

Phi(Bending): 0.900 Phi(Shear): 0.850 Phi(Torsion): 0.850

Flexural Reinforcement for Major Axis Moment------- End-I --------- --------- Middle -------- --------- End-J ---------Rebar Area Rebar % Rebar Area Rebar % Rebar Area Rebar %

2.253 1.877 0.390 0.325 2.253 1.877 Top (+2 Axis)1.197 0.997 0.757 0.631 1.106 0.922 Bot (-2 Axis)

Design Mu Station Loc Design Mu Station Loc Design Mu Station Loc-1089.509 0.000 -217.917 90.000 -1089.583 135.000 Top (+2 Axis)606.966 0.000 405.299 45.000 567.327 135.000 Bot (-2 Axis)

Controlling Combo Controlling Combo Controlling ComboUDCON18 UDCON17 UDCON17 Top (+2 Axis)UDCON17 UDCON17 UDCON18 Bot (-2 Axis)

Shear Reinforcement for Major Shear (V2)------- End-I --------- --------- Middle -------- --------- End-J ---------Rebar Av/s Rebar Av/s Rebar Av/s

0.028 0.014 0.028

Design Vu Station Loc Design Vu Station Loc Design Vu Station Loc25.279 0.000 17.502 90.000 25.377 135.000

Controlling Combo Controlling Combo Controlling ComboUDCON18 UDCON18 UDCON17

Torsion Reinforcement------- Shear --------- ------ Longitudinal -----Rebar At/s Rebar Al

0.000 0.000

Design Tu Station Loc Design Tu Station Loc4.426 135.000 4.426 135.000

Controlling Combo Controlling ComboUDCON4 UDCON4


SB - 12x10

Stair Design Chapter 08

Page 57

8.1 Sample calculation of stair (flight 1):

Min thickness of waist slab = 5 in

Max thickness of waist slab = 9 in

So, avg. Thickness, t = 7 in

Ver. Length of waist slab = 5.1 ft

Height = 3.5 ft

So, inclined length = √5.12 + 3.52 = 6.2 ft

Self-weight of waist slab = (5/12) *6.2*150 = 386.59 lb/ft

Wt. of stair (rise + trade) = [0.5*(6/12) *(8.5/12) *6*150] = 159.38 lb/ft

floor finish = 13.2*25 = 329.64 lb/ft

total = 875.60 lb/ft

UDL (DL) = 875.62/13.2 = 66.41 psf factored DL = 1.4*66.41 = 93 psf

UDL (LL) = 100 psf factored LL = 1.7*100 = 170 psf

Total Wu = 263 psf

So, moment, M = 263 ∗ 13.22

9 = 5079.88 lb-ft

8.1.1 Check d:

Pmax = 0.75*0.85*0.85*(3/60) *[0.003/ (0.003+0.004)] = 0.012

Dreq = √𝑀𝑢

∅𝜌𝑓𝑦𝑏(1−0.59𝜌𝑓𝑦

𝑓′𝑐

) = √

5079.88

0.9∗0.012∗60000∗12∗(1−0.59∗0.012∗60

3) = 3.06 < dprovide; OK

Overall depth of waist slab, t = 7 in

Effective depth of waist slab, d = 7 in – 1 in cover = 6 in

8.1.2 Reinforcement:

Temp. & shrinkage rebar: Asmin = 0.002bt = 0.002*12*7 = 0.17 in2; so provide #[email protected]” c/c

Principal rebar: Assume a = 0.4 in; As = 5079.88∗12

0.9∗60000∗(6−0.4

2) = 0.19 in2; so provide #[email protected]” c/c

Check a = (0.19*60)/ (0.85*3*12) = 0.38; Ok

Bottom landing length = 3 ft

Top landing length = 4 ft

Total length = 13.2 ft

No. of rise/trade = 6

Rise length = 6 in

Trade length = 8.5 in


Page 58

Fig: Stair Layout

Fig: Flight 1

Stair Design

height = 3.5 ft.

Chapter 08

Page 59

Fig: Flight 2

Fig: Flight 3

Stair Design

height = 3 ft.

height = 3.5 ft.

Chapter 08

Page 60



0.85𝑓′𝑐𝑏

=(3 ∗ 0.79 − 2 ∗ 0.60) ∗ 60

0.85 ∗ 3 ∗ 10

= 2.75



2) + ∅𝐴′𝑠𝑓𝑦(𝑑 − 𝑑′)

= 0.9 ∗ (3 ∗ 0.79 − 2 ∗ 0.60) ∗ 60 ∗ (10.5 −2.75

2)

+0.9 ∗ 2.37 ∗ 60 ∗ (10.5 − 1.5)

= 1728.34 kip − in > 1089.58 kip − in [ETABS]

Section is OK



∅𝑣𝑐 = ∅2√𝑓′𝑐 ∗ 𝑏𝑑

= 0.85 ∗ 2 ∗ √3000*10*10.5

= 9776.85 lb

= 9.78 kip


∅

=25.38 − 9.78

0.85

= 18.35 kip

So, ∅𝑣𝑐 < 𝑣𝑠; provide stirrup #3@5"c/c at edge

#[email protected]”c/c at mid

[𝑑2⁄ = 10

2⁄ = 5" & ∅Avfyd

VU-∅VC

=0.85*2*.11*60*10

25.38-9.78=7.5" & 24"]


Page 61

Chapter 09 Underground Water

Reservoir

Page 62

Design of Underground Water Reservoir Tank

9.1 Design of Underground Water Reservoir

Tank (RCC Box)

Per capita consumption = 235 lpcd

6 person/apartment, single apartment,

3 days storage =235× 6 × 3

= 4230 liter

= 148.9 𝑐𝑓𝑡

∴ Capacity ≅ 150 𝑐𝑓𝑡

Assume depth of tank = 5 ft.

∴ Tank area = 150

5

= 30 𝑓𝑡2

Tank dimension = 6′ × 5′ × (5 + 1)′

1’ freeboard, gives total depth = 6’

Thickness of side wall and base slab = 6”

Cover slab thickness = 6”

9.1.1 Base Slab Design

Assume, GWT at GL.

Upward water pressure = 𝛾𝑤h

= 62.4 × (6′ + 612)⁄

= 405.6 psf (↑)

Weight of base slab = 9× 612⁄ × 6 × 150

= 4050 lb.

Weight of cover slab = 7× 612⁄ × 6 × 150 =

3150 lb.

Weight of side wall = 6 12⁄ × 6 × 150× (6.5 ×

5.5) × 2

= 10800 lb.

Total weight of tank = 4050+4150 + 10800

= 18000 lb.

Area of base slab = 9’× 6′

= 54 𝑓𝑡2

∴ Downward pressure, = 18000

54

= 333.333 psf (↓)

∴ Net upward pressure = (405.6−333.333)

= 72.27 psf (↑)

Using moment co-efficient method:

M = 𝐴

𝐵 =

6

5 = 1.2< 2

∴ Two-way slab.

All side are discontinuous, so case no 1.

M = 𝑙𝑎

𝑙𝑏 =

5

6 = 0.833

𝐶𝑎 =0.0520 & 𝐶𝑏=0.0249

Effective depth from bottom = 6" − (1 +

(0.375/2))

= 4.813”

Short direction:

𝑀𝑎 𝑝𝑜𝑠𝑠 𝑙𝑙 =𝐶𝑎 𝑙𝑙W𝑙𝑎2

= 0.0524 X 72.27 X52

= 94.023 lb-ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 94.023 ×12

0.9 ×12 ×4.8132

= 4.51

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

Chapter 9

Page 63


= 0.85 3

60 [1−√(1 −

2×4.51

0.85×3000)] 12× 4.813

= 0.01302 𝑖𝑛2

𝐴𝑠 𝑚𝑖𝑛 = 0.002bh = 0.002× 12 × 6 =0.144 𝑖𝑛2

Spacing = 0.11

0.144× 12 = 9.17” 𝑐/𝑐 ≅ 9” c/c

(#3)

Long direction:

𝑀𝑏 𝑝𝑜𝑠𝑠 𝑙𝑙 = 𝐶𝑏 𝑙𝑙W𝑙𝑏2

= 0.0249 X 72.27 X62

= 65 lb –ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 65 ×12

0.9 ×12 ×4.8132

= 3.12

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×3.12

0.85×3000)] 12× 4.813

= 0.009 𝑖𝑛2

𝐴𝑠 𝑚𝑖𝑛 = 0.002bh = 0.002× 12 × 6 =0.144 𝑖𝑛2

Spacing = 0.11

0.144×12

= 9” c/c (#3)

9.1.2 Design of Cover Slab

Dead load, = 6/12 × 150 =75 psf

Live load, = 40 psf

∴ 𝑊𝑈 = (1.4× 75) + (1.7 × 40) = 105+64 = 173

psf

∴ M = 𝑊𝑙2

8 =

173×62

8 = 778.5 lb –ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 778.5 ×12

0.9 ×12 ×4.8132

= 37.34

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

40 [1−√(1 −

2×37.34

0.85×3000)] 12× 4.813

= 0.107 𝑖𝑛2

𝐴𝑠 𝑚𝑖𝑛 = 0.002bh = 0.002× 12 × 6 = 0.144 𝑖𝑛2

Spacing = 0.11

0.144×12 = 9” c/c (#3)

Temperature and shrinkage reinforcement,

= 0.002bh = 0.002× 12 × 6 = 0.144 𝑖𝑛2

Spacing = 0.11

0.144×12 = 9” c/c (#3)

Chapter 9

Page 64


9.1.3 Design of Side Wall (Vertical Bar)

Effective depth of wall = 6−(1 + 1) = 4”

Unit weight of soil, 𝛾𝑠𝑜𝑖𝑙 = 120 psf

Unit weight of water, 𝛾𝑤 = 62.5 psf

Angle of internal friction, 𝜑= 30°

∴ Active pressure, 𝐾𝑎= 1−𝑠𝑖𝑛𝜑

1+𝑠𝑖𝑛𝜑 =

1−𝑠𝑖𝑛30°

1+𝑠𝑖𝑛30° = 0.333

Now, 𝛾 = 𝛾𝑤+ 𝐾𝑎𝛾𝑠𝑜𝑖𝑙

= 62.5+0.333(120−62.5)

= 81.67 psf

Now, h = H/3 =6/4 =1.5’≤3

∴ h = 3’

M = 𝛾𝐻ℎ2

6 =

81.67×6×32

6 = 735 lb –ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 735 ×12

0.9 ×12 ×42

= 51

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

40 [1−√(1 −

2×51

0.85×3000)] 12× 4

= 0.122 𝑖𝑛2

𝐴𝑠 𝑚𝑖𝑛 = 0.002bh = 0.002× 12 × 6 = 0.144 𝑖𝑛2

Spacing = 0.11

0.144×12 = 9” c/c (#3) in long as

well as short direction.

Now for horizontal bar:

P = 𝛾(𝐻 − ℎ) = 81.67(6−3) =245 psf

For short (B=5’):

M = ±𝑃𝐵2

14 =

245×52

14 = 437.5 lb –ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 437.5 ×12

0.9 ×12 ×42

= 30.38

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

40 [1−√(1 −

2×30.38

0.85×3000)] 12× 4

= 0.109 𝑖𝑛2

Spacing = 0.11

0.109×12 = 12” c/c (#3)

Long direction, L=6’:

M = ±𝑃𝐿2

14 =

245×62

14 = 630 lb –ft

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2 = (630 ×12)/ (0.9 ×12 ×4^2) = 43.75

Chapter 9

Page 65


𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd = 0.85

3

40 [1−√(1 −

2×43.75

0.85×3000)] 12× 4 = 0.105 𝑖𝑛2

Spacing = 0.11

0.105×12 = 12” c/c (#3)

Fig: U.W.T Reinforced Detailing

Chapter 9

Page 66

Chapter 10 Overhead Water

Tank Design

Page 67

Design of Roof Water Tank

10.1 Design of Roof Water Tank:

Water consumption =235 lpcd (BNBC)

6 Person/ Apartment, 6 Apartment

So total water required = 6X6X235

= 8460 Liter/day

=8460X0.03531

=298.723 cft/day

If pump one times after every two days,

Total water consumption =298.723X2

=597.45 cft/2days

So tank area = 120 𝑓𝑡2

= 12 ft X 10 ft

Tank height =597.45/120

=4.978 ft

≅ 5 ft

10.1.1 Design of Base Slab

Water pressure at bottom, 𝛾𝑤h =62.4X5 Psf

=312

Psf

Thickness of slab = [ {(12+10) x2}/ 180] x12

= 3.04 inch

≅ 3.5 inch

Self weight of slab = (3.5/12) x 150

= 43.75 Psf

= 498.05 Psf

𝑙𝑏

𝑙𝑎 =

12

10 = 1.2 < 2 , so two-way slab & case no 1

As case no 1, so there is no negative moment.

M = 𝑙𝑎

𝑙𝑏 =

10

12 = 0.833

Factored DL = 1.4 X (312+43.75)

𝐶𝑎 =0.046 & 𝐶𝑏=0.028

𝑀𝑎 𝑝𝑜𝑠𝑠 𝑑𝑙 = 𝐶𝑎 𝑑𝑙W𝑙𝑎2

= 0.046 X 498.05 X102

= 2291.O3 lb-ft

𝑀𝑏 𝑝𝑜𝑠𝑠 𝑑𝑙 = 𝐶𝑏 𝑑𝑙W𝑙𝑏2

= 0.028 X 498.05 X122

= 2008.14 lb -ft

10.1.2 Reinforcement:

There is no reinforcement required for live load

(no live load on slab)

Short direction:

Moment =2251.03 lb -ft.

(3.5 −1.187)

Width of strip = 12 inch

= 2.313 inch

Effective depth = 2.313 inch

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 2251.03 ×12

0.9 ×12 ×2.3132

= 467.51

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×467.51

0.85×3000)] 12× 2.313

Chapter 10

Page 68

Design of Roof Water Tank

= 0.241 𝑖𝑛2

𝐴𝑠 𝑚𝑖𝑛 = 0.002bh = 0.002× 12 × 3.5 =0.084

𝑖𝑛2

Spacing = 0.11

0.241× 12

= 5.48 𝑖𝑛 c/c

≅ 5 𝑖𝑛 c/c (#3)

Maximum spacing =2h =2× 3.5 = 7 𝑖𝑛

Long direction:

Moment = 2008.14 lb -ft.

(3.5 −1.187)

Width of strip = 12 inch

= 2.313 inch

Effective depth = 2.313 inch

𝑅𝑛 = 𝑀

𝜙𝑏𝑑2

= 2008.13 ×12

0.9 ×12 ×2.3132

= 417.06

𝐴𝑠 = 0.85 𝑓𝑐

′

𝑓𝑦 [1−√(1 −

2𝑅𝑛

0.85𝑓𝑐′)] bd

= 0.85 3

60 [1−√(1 −

2×417.06

0.85×3000)] 12× 2.313

= 0.212 𝑖𝑛2

Spacing = 0.11

0.212× 12

= 6.23 𝑖𝑛 ≅ 6 𝑖𝑛 ( #3)

Fig: O.W.T Reinforced Detailing

Chapter 10

Page 69

Chapter 11

Septic Tank Design

Page 70

11.1 This septic tank design was performed in pre-calculated Excel sheet & default drawings. For

details please take tour in page#134 of Water Supply and Sanitation by M. Feroze Ahmed & Md.

Mujubur Rahman.

Population, P = 30 Person Ratio Length = 4.425 m

Flow, q = 90 lpcd a = 3 Width = 1.500 m

Desludging frequency, N = 3 years b = 1 Height = 1.950 m

Design Temperature, T = 25 ˚C c = 1

Sludge Accumulation Rate, C = 0.06 m3/person/year Freeboard = 0.3 m

Rounding = 0.075 m

Sedimentation

th = 0.470591 days Vh/A = 0.196883

Vh = 1.270595 m30.82-.26A = -0.85792

Sludge Digestion 0.3 0.375

td = 42.31796 days hh = 0.375

Vd = 0.634769 m3 hd = 0.09836 m

Sludge

Vsl = 5.4 m3 hsl = 0.836749

hsc = 0.3347

Volume = 9.465365 m3

4.400

x = 1.466691 1.467

Area = 6.45355 h = 1.644808 1.945

Septic Tank Design Chapter 11

Page 71

Chapter 12Appendix

Page 72

TABLE A.1: Designations, Diameters, Areas and Weights of Standard Bars

Bar No.

Diameter, in

Cross-Sectional Area, in2

Nominal Weight,

lb/ft Inch-Pound SI

3 10 0.375 0.11 0.376 4 13 0.500 0.20 0.668 5 16 0.625 0.31 1.043 6 19 0.750 0.44 1.502 7 22 0.875 0.60 2.044 8 25 1.000 0.79 2.670 9 29 1.128 1.00 3.400

10 32 1.270 1.27 4.303 11 36 1.410 1.56 5.313 14 49 1.693 2.25 7.650 18 57 2.257 4.00 13.600

TABLE A.2 : Simplified tension development length in bars diameter ld/db for uncoated bars and nominalweight concrete

Appendix Chapter 12

Page 73

TABLE A.3 : Development length in compression, in. for nominalweight concrete ldc= greater of (0.02fy/ 풇′풄)db or 0.0003fydb (Minimun length 8 in. in all caes)

TABLE A.4 : Unit weight w, effective angels of internal friction Ø, and coefficients of friction with concrete f

Appendix Chapter 12

Page 74

Table 6.6.11 Coefficients for Negative Moments in Slabs †

M a, neg C a ,neg w a

2

Mb , neg Cb, neg w b2 Where w = total uniform dead plus live load per unit area

Ratio

m = a b

Case 1

Case 2

Case 3

Case 4

Case 5

Case 6

Case 7

Case 8

Case 9

Ca, neg 1.00 Cb, neg

0.045

0.045

0.076

0.050

0.050

0.075 0.071

0.071

0.033

0.061

0.061

0.033


0.050

0.041

0.072

0.055

0.045

0.079 0.075

0.067

0.038

0.056

0.065

0.029


0.055

0.037

0.070

0.060

0.040

0.080 0.079

0.062

0.043

0.052

0.068

0.025


0.060

0.031

0.065

0.066

0.034

0.082 0.083

0.057

0.049

0.046

0.072

0.021


0.065

0.027

0.061

0.071

0.029

0.083 0.086

0.051

0.055

0.041

0.075

0.017


0.069

0.022

0.056

0.076

0.024

0.085 0.088

0.044

0.061

0.036

0.078

0.014


0.074

0.017

0.050

0.081

0.019

0.086 0.091

0.038

0.068

0.029

0.081

0.011


0.077

0.014

0.043

0.085

0.015

0.087 0.093

0.031

0.074

0.024

0.083

0.008


0.081

0.010

0.035

0.089

0.011

0.088 0.095

0.024

0.080

0.018

0.085

0.006


0.084

0.007

0.028

0.092

0.008

0.089 0.096

0.019

0.085

0.014

0.086

0.005


0.086

0.006

0.022

0.094

0.006

0.090 0.097

0.014

0.089

0.010

0.088

0.003

† A crosshatched edge indicates that the slab continues across, or fixed at the support; an unmarked edge indicates a support at which torsional resistance is negligible.

Appendix Chapter 12

Page 75

Table 6.6.12 Coefficients for Dead Load Positive Moments in Slabs †

M a, pos , dl Ca ,d l w a

2

Mb , pos , dl Cb ,d l wb

2 Where w = uniform dead load per unit area Ratio

m = a b

Case 1

Case 2

Case 3

Case 4

Case 5

Case 6

Case 7

Case 8

Case 9

Ca,dl 1.00 Cb,dl

0.036

0.036

0.018

0.018

0.018

0.027

0.027

0.027

0.027

0.018

0.033

0.027

0.027

0.033

0.020

0.023

0.023

0.020

Ca,dl 0.95 Cb,dl

0.040

0.033

0.020

0.016

0.021

0.025

0.030

0.024

0.028

0.015

0.036

0.024

0.031

0.031

0.022

0.021

0.024

0.017

Ca,dl 0.90 Cb,dl

0.045

0.029

0.022

0.014

0.025

0.024

0.033

0.022

0.029

0.013

0.039

0.021

0.035

0.028

0.025

0.019

0.026

0.015

Ca,dl 0.85 Cb,dl

0.050

0.026

0.024

0.012

0.029

0.022

0.036

0.019

0.031

0.011

0.042

0.017

0.040

0.025

0.029

0.017

0.028

0.013

Ca,dl 0.80 Cb,dl

0.056

0.023

0.026

0.011

0.034

0.020

0.039

0.016

0.032

0.009

0.045

0.015

0.045

0.022

0.032

0.015

0.029

0.010

Ca,dl 0.75 Cb,dl

0.061

0.019

0.028

0.009

0.040

0.018

0.043

0.013

0.033

0.007

0.048

0.012

0.051

0.020

0.036

0.013

0.031

0.007

Ca,dl 0.70 Cb,dl

0.068

0.016

0.030

0.007

0.046

0.016

0.046

0.011

0.035

0.005

0.051

0.009

0.058

0.017

0.040

0.011

0.033

0.006

Ca,dl 0.65 Cb,dl

0.074

0.013

0.032

0.006

0.054

0.014

0.050

0.009

0.036

0.004

0.054

0.007

0.065

0.014

0.044

0.009

0.034

0.005

Ca,dl 0.60 Cb,dl

0.081

0.010

0.034

0.004

0.062

0.011

0.053

0.007

0.037

0.003

0.056

0.006

0.073

0.012

0.048

0.007

0.036

0.004

Ca,dl 0.55 Cb,dl

0.088

0.008

0.035

0.003

0.071

0.009

0.056

0.005

0.038

0.002

0.058

0.004

0.081

0.009

0.052

0.005

0.037

0.003

Ca,dl 0.50 Cb,dl

0.095

0.006

0.037

0.002

0.080

0.007

0.059

0.004

0.039

0.001

0.061

0.003

0.089

0.007

0.056

0.004

0.038

0.002

† A crosshatched edge indicates that the slab continues across, or is fixed at the support; an unmarked edge indicates a support at which torsional resistance is negligible.

Appendix Chapter 12

Page 76

Table 6.6.13 Coefficients for Live Load Positive Moments in Slabs †

M a, pos , ll Ca ,ll w a

2

Mb , pos , ll Cb ,ll w b

2 Where w = uniform live load per unit area Ratio

m = a b

Case 1

Case 2

Case 3

Case 4

Case 5

Case 6

Case 7

Case 8

Case 9

Ca,ll 1.00 Cb,ll

0.036

0.036

0.027

0.027

0.027

0.032

0.032

0.032

0.032

0.027

0.035

0.032

0.032

0.035

0.028

0.030

0.030

0.028

Ca,ll 0.95 Cb,ll

0.040

0.033

0.030

0.025

0.031

0.029

0.035

0.029

0.034

0.024

0.038

0.029

0.036

0.032

0.031

0.027

0.032

0.025

Ca,ll 0.90 Cb,ll

0.045

0.029

0.034

0.022

0.035

0.027

0.039

0.026

0.037

0.021

0.042

0.025

0.040

0.029

0.035

0.024

0.036

0.022

Ca,ll 0.85 Cb,ll

0.050

0.026

0.037

0.019

0.040

0.024

0.043

0.023

0.041

0.019

0.046

0.022

0.045

0.026

0.040

0.022

0.039

0.020

Ca,ll 0.80 Cb,ll

0.056

0.023

0.041

0.017

0.045

0.022

0.048

0.020

0.044

0.016

0.051

0.019

0.051

0.023

0.044

0.019

0.042

0.017

Ca,ll 0.75 Cb,ll

0.061

0.019

0.045

0.014

0.051

0.019

0.052

0.016

0.047

0.013

0.055

0.016

0.056

0.020

0.049

0.016

0.046

0.013

Ca,ll 0.70 Cb,ll

0.068

0.016

0.049

0.012

0.057

0.016

0.057

0.014

0.051

0.011

0.060

0.013

0.063

0.017

0.054

0.014

0.050

0.011

Ca,ll 0.65 Cb,ll

0.074

0.013

0.053

0.010

0.064

0.014

0.062

0.011

0.055

0.009

0.064

0.010

0.070

0.014

0.059

0.011

0.054

0.009

Ca,ll 0.60 Cb,ll

0.081

0.010

0.058

0.007

0.071

0.011

0.067

0.009

0.059

0.007

0.068

0.008

0.077

0.011

0.065

0.009

0.059

0.007

Ca,ll 0.55 Cb,ll

0.088

0.008

0.062

0.006

0.080

0.009

0.072

0.007

0.063

0.005

0.073

0.006

0.085

0.009

0.070

0.007

00.063

0.006

Ca,ll 0.50 Cb,ll

0.095

0.006

0.066

0.004

0.088

0.007

0.077

0.005

0.067

0.004

0.078

0.005

0.092

0.007

0.076

0.005

0.067

0.004

† A crosshatched edge indicates that the slab continues across, or is fixed at the support; an unmarked edge indicates a support at which torsional resistance is negligible.

Appendix Chapter 12

Page 77

Table 6.2.9 Structural Importance Coefficient CI (for Wind load)

Structural importance category Structural importance coefficient C1 I Essential Facilities 1.25 II Hazardous Facilities 1.25 III Special Occupancy Structures 1.00 IV Standard Occupancy Structures 1.00 V Low-risk Structures 0.88

Table 6.2.23

Structural Importance Coefficient CI (for Earthquake load)

Structural importance category Structural importance coefficient C1 I I’

I Essential Facilities 1.25 1.50 II Hazardous Facilities 1.25 1.50 III Special Occupancy Structures 1.00 1.00 IV Standard Occupancy Structures 1.00 1.00 V Low-risk Structures 1.00 1.00

Table 6.2.22 Seismic Zone Coefficient, Z

Seismic Zone Zone coefficient Zone 1 0.075 Zone 2 0.15 Zone 3 0.25

Appendix Chapter 12

Page 78

Table 6.2.25 Site Coefficient, S for Seismic Lateral Forces

Site Soil Characteristics Coefficient, S

Type Description

S1 A soil profile with either :

a) b)

A rock-like material characterized by a shear-wave velocity greater than 762 m/s or by other suitable means of classification, or Stiff or dense soil condition where the soil depth is less than 61 meters

1.0

S2 A soil profile with dense or stiff soil conditions, where the soil depth exceeds 61 meters

1.2

S3 A soil profile 21 meters or more in depth and containing more than 6 meters of soft to medium stiff clay but not more than 12 meters of soft clay

1.5

S4 A soil profile containing more than 12 meters of soft clay characterized by a shear wave velocity less than 152 m/s

2.0

Note : (1)

The site coefficient shall be established from properly substantiated geotechnical data. In locations where the soil properties are not known in sufficient detail to determine the soil profile type, soil profile S3 shall be used. Soil profile S4 need not be assumed unless the building official determines that soil profile S4 may be present at the site, or in the event that soil profile S4 is established by geotechnical data.

Table 6.2.15

Overall Pressure Coefficients, Cp for Rectangular Buildings with Flat Roofs

h/B L/B

0.1 0.5 0.65 1.0 2.0 > 3.0 <0.5

10.0

20.0

≥40.0

1.40

1.55

1.80

1.95

1.45

1.85

2.25

2.50

1.55

2.00

2.55

2.80

1.40

1.70

2.00

2.20

1.15

1.30

1.40

1.60

1.10

1.15

1.20

1.25

Note: (1)

(2)

These coefficients are to be used with Method-2 given in Sec

2.4.6.6a(ii). Use Cp = + 0.7 for roof in all cases. Linear interpolation may be made for intermediate values of` h/B

and L/B.

Appendix Chapter 12

Page 79

Table 6.2.24

Response Modification Coefficient for Structural Systems, R

Basic Structural System

Description of Lateral Force Resisting System R

a. Building Frame

System

1. Steel eccentric braced frame (EBF) 2. Light framed walls with shear panels i) Plywood walls for structures 3-storeys or less ii) All other light framed walls 3. Shear walls i) Concrete ii) Masonry 4. Concentric braced frames (CBF) i) Steel ii) Concrete (3) iii) Heavy timber

10

9 7

8 8

8 8 8

b. Moment Resisting

Frame System

1. Special moment resisting frames (SMRF) i) Steel ii) Concrete 2. Intermediate moment resisting frames (IMRF), concrete(4) 3. Ordinary moment resisting frames (OMRF) i) Steel ii) Concrete (5)

12 12 8

6 5

c. Dual System

1. Shear walls i) Concrete with steel or concrete SMRF ii) Concrete with steel OMRF

iii) Concrete with concrete IMRF (4) iv) Masonry with steel or concrete SMRF v) Masonry with steel OMRF vi) Masonry with concrete IMRF (3) 2. Steel EBF i) With steel SMRF ii) With steel OMRF 3. Concentric braced frame (CBF) i) Steel with steel SMRF ii) Steel with steel OMRF

iii) Concrete with concrete SMRF (3) iv) Concrete with concrete IMRF (3)

12 6 9 8 6 7

12 6

10 6 9 6

Appendix Chapter 12

Page 80

Table 6.2.8 Basic Wind Speeds for Selected Locations in Bangladesh

Location Basic Wind Speed (km/h) Location Basic Wind

Speed (km/h)

Angarpota Bagerhat

Bandarban Barguna Barisal

Bhola Bogra

Brahmanbaria Chandpur

Chapai Nawabganj

Chittagong Chuadanga

Comilla Cox’s Bazar Dahagram

Dhaka

Dinajpur Faridpur

Feni Gaibandha

Gazipur

Gopalganj Habiganj

Hatiya Ishurdi

Joypurhat Jamalpur Jessore

Jhalakati Jhenaidah

Khagrachhari

Khulna Kutubdia

Kishoreganj Kurigram

Kushtia

Lakshmipur

150 252 200 260 256

225 198 180 160 130

260 198 196 260 150

210 130 202 205 210

215 242 172 260 225

180 180 205 260 208

180 238 260 207 210

215 162

Lalmonirhat Madaripur

Magura Manikganj Meherpur

Maheshkhali Moulvibazar Munshiganj

Mymensingh Naogaon

Narail

Narayanganj Narsinghdi

Natore Netrokona

Nilphamari

Noakhali Pabna

Panchagarh Patuakhali

Pirojpur Rajbari

Rajshahi Rangamati

Rangpur

Satkhira Shariatpur

Sherpur Sirajganj

Srimangal

St. Martin’s Island Sunamganj

Sylhet Sandwip Tangail

Teknaf

Thakurgaon

204 220 208 185 185

260 168 184 217 175

222 195 190 198 210

140 184 202 130 260

260 188 155 180 209

183 198 200 160 160

260 195 195 260 160

260 130

Appendix Chapter 12

Page 81

Table 6.2.10 Combined Height and Exposure Coefficient, Cz

Height above Coefficient, Cz (1) ground level, z

(meters) Exposure A Exposure B Exposure C

0-4.5 6.0 9.0

12.0

15.0 18.0 21.0 24.0

27.0 30.0 35.0 40.0

45.0 50.0 60.0 70.0

80.0 90.0

100.0 110.0

120.0 130.0 140.0 150.0

160.0 170.0 180.0 190.0

200.0 220.0 240.0 260.0

280.0 300.0

0.368 0.415 0.497 0.565

0.624 0.677 0.725 0.769

0.810 0.849 0.909 0.965

1.017 1.065 1.155 1.237

1.313 1.383 1.450 1.513

1.572 1.629 1.684 1.736

1.787 1.835 1.883 1.928

1.973 2.058 2.139 2.217

2.910 2.362

0.801 0.866 0.972 1.055

1.125 1.185 1.238 1.286

1.330 1.371 1.433 1.488

1.539 1.586 1.671 1.746

1.814 1.876 1.934 1.987

2.037 2.084 2.129 2.171

2.212 2.250 2.287 2.323

2.357 2.422 2.483 2.541

2.595 2.647

1.196 1.263 1.370 1.451

1.517 1.573 1.623 1.667

1.706 1.743 1.797 1.846

1.890 1.930 2.002 2.065

2.120 2.171 2.217 2.260

2.299 2.337 2.371 2.404

2.436 2.465 2.494 2.521

2.547 2.596 2.641 2.684

2.724 2.762

Note : (1) Linear interpolation is acceptable for intermediate values of z.

Appendix Chapter 12

Page 82

Table 6.2.11 Gust Response Factors, Gh and Gz

Height above Gh (2)and Gz

ground level (meters) Exposure A Exposure B Exposure C

0-4.5 6.0 9.0

12.0

15.0 18.0 21.0 24.0

27.0 30.0 35.0 40.0

45.0 50.0 60.0 70.0

80.0 90.0

100.0 110.0

120.0 130.0 140.0 150.0

160.0 170.0 180.0 190.0

200.0 220.0 240.0

260.0 280.0 300.0

1.654 1.592 1.511 1.457

1.418 1.388 1.363 1.342

1.324 1.309 1.287 1.268

1.252 1.238 1.215 1.196

1.180 1.166 1.154 1.114

1.134 1.126 1.118 1.111

1.104 1.098 1.092 1.087

1.082 1.073 1.065

1.058 1.051 1.045

1.321 1.294 1.258 1.233

1.215 1.201 1.189 1.178

1.170 1.162 1.151 1.141

1.133 1.126 1.114 1.103

1.095 1.087 1.081 1.075

1.070 1.065 1.061 1.057

1.053 1.049 1.046 1.043

1.040 1.035 1.030

1.026 1.022 1.018

1.154 1.140 1.121 1.107

1.097 1.089 1.082 1.077

1.072 1.067 1.061 1.055

1.051 1.046 1.039 1.033

1.028 1.024 1.020 1.016

1.013 1.010 1.008 1.005

1.003 1.001 1.000 1.000

1.000 1.000 1.000

1.000 1.000 1.000

Note : (1)

For main wind-force resisting systems, use building or structure height h for z. Linear interpolation is acceptable for intermediate values of z.

Appendix Chapter 12

Page 83

Reference

Design of Concrete Structures by Arthr H. Nilson, David Darwin, Charles W.Dolan

Structural Concrete (Theory and Design) by M. Nadim Hassoun and AthemAl- ManaseerBangladesh National Building Code (BNBC) 2006Reinforced Concrete Manual & Building Plan by Engr. Sharifur Rahman, Engr. Abul Faraz KhanEngineering Mechanics of Solids by Egor P. PopovWater Supply & Sanitation by M. Feroze Ahmed, Md. Mujibur RahmanPrincipal of Geotechnical Engineering by Braja M. Das

https://en.wikipedia.org/wiki/Column

https://en.wikipedia.org/wiki/Beam

https://en.wikipedia.org/wiki/Slab

https://en.wikipedia.org/wiki/Rebar

https://www.ce.memphis.edu/6136/PDF_notes/E_column_biaxial.pdf

https://en.wikipedia.org/wiki/Special:Search?search=type+of+foundation&go=Go

R.C.C Manual & Building Plan by Khan & Rahman

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