design of six storied residential apartment building
TRANSCRIPT
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.
Project Overviews Chapter 01
Page 4
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
Project Overviews Chapter 01
Page 5
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
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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
Structural Design Criteria & Consideration Chapter 02
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
Structural Design Criteria & Consideration Chapter 02
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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
Structural Design Criteria & Consideration Chapter 02
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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
Structural Design Criteria & Consideration Chapter 02
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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
Structural Design Criteria & Consideration Chapter 02
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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
Structural Design Criteria & Consideration Chapter 02
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Chapter 03
Architectural
Drawings
Page 14
Architectural Plan & Elevation Chapter 03
3.1 Typical Floor Plan
Page 15
Architectural Plan & Elevation Chapter 03
3.2 Ground Floor Plan
Page 16
Architectural Plan & Elevation Chapter 03
3.4 Elevation
Page 17
Architectural Plan & Elevation Chapter 03
Page 18
Architectural Plan & Elevation Chapter 03
Page 19
Architectural Plan & Elevation Chapter 03
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Chapter 04
Slab Design
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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
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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
Slab Design Chapter 04
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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
Slab Design Chapter 04
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Slab Design Chapter 04
Page 25
Slab Design Chapter 04
Page 26
Slab Design Chapter 04
Page 27
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
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
Beam Design Chapter 05
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
Beam Design Chapter 05
Page 31
Fig: FB rebar layout (12”x10”) [End]
Fig: FB rebar layout (12”x10”) [Mid]
Reinforcement detailing of FB (12”x10”)
Beam Design Chapter 05
Page 32
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 : 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
Beam Design Chapter 05
Page 33
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)
5.2.2 Moment capacity check:
𝑎 =(𝐴′𝑠 − 𝐴𝑠)𝑓𝑦
0.85𝑓′𝑐𝑏
=(3 ∗ 0.60 − 3 ∗ 0.44) ∗ 60
0.85 ∗ 3 ∗ 12
= 0.94
∅ = 0.9 [from ETABS]
∅𝑀𝑛 = ∅(𝐴′𝑆 − 𝐴𝑠)𝑓𝑦 (𝑑 −𝑎
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
Beam Design Chapter 05
Page 34
5.2.3 Stirrup check:
Vu = 12.88 kip [ETABS]
∅𝑣𝑐 = ∅2√𝑓′𝑐 ∗ 𝑏𝑑
= 0.85 ∗ 2 ∗ √3000*12*10
= 11173.54 lb
= 11.17 kip
𝑣𝑠 =𝑣𝑢 − ∅𝑣𝑐
∅
=12.88 − 11.17
0.85
= 2.01 kip
So, ∅𝑣𝑐 > 𝑣𝑠; no stirrup need, but we give minimum stirrup #3@5"c/c
Beam Design Chapter 05
Page 35
Reinforcement detailing &
section of GB (12”x12”)
Beam Design Chapter 05
Page 36
Chapter 06
Column Design
Page 37
ETABS Concrete Design
ETABS v9.7.4 - File:Etabs_Capstone - Kip-in Units
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
ETABS Concrete Design
ETABS v9.7.4 - File:Etabs_Capstone - Kip-in Units
ACI 318-99 COLUMN SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope) Level : GF L=96.000 Element : C10 B=12.000 D=18.000 dc=1.800 Section ID : C12X18 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 2.160 1.000 Bottom 3.478 1.610
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
Shear Reinforcement for Major Shear (V2) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.010 12.746 84.000 UDCON15 Bottom 0.010 12.746 0.000 UDCON15
Shear Reinforcement for Minor Shear (V3) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.000 8.660 84.000 UDCON17 Bottom 0.000 8.660 0.000 UDCON17 Joint Shear Check/Design Joint Shear Shear Shear Joint Controlling Ratio VuTot phi*Vc Area Combo Major(V2) 0.697 105.186 150.843 216.000 UDCON15 Minor(V3) 0.615 74.259 120.674 216.000 UDCON15
C2-12x18
Column Design Chapter 06
Page 39
ETABS Concrete Design
ETABS v9.7.4 - File:Etabs_Capstone - Kip-in Units
ACI 318-99 COLUMN SECTION DESIGN Type: Sway Intermediate Units: Kip-in (Envelope) Level : GF L=96.000 Element : C8 B=15.000 D=18.000 dc=1.800 Section ID : C15X18 E=3122.000 fc=3.000 Lt.Wt. Fac.=1.000 fy=60.000 fys=60.000 RLLF=0.895 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 2.700 1.000 Bottom 3.868 1.432
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
Shear Reinforcement for Major Shear (V2) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.013 15.961 84.000 UDCON15 Bottom 0.013 15.961 0.000 UDCON15
Shear Reinforcement for Minor Shear (V3) Column End Rebar Av/s Design Vu Station Loc Controlling Combo Top 0.015 15.297 84.000 UDCON17 Bottom 0.015 15.297 0.000 UDCON17 Joint Shear Check/Design Joint Shear Shear Shear Joint Controlling Ratio VuTot phi*Vc Area Combo Major(V2) 0.658 124.056 188.553 270.000 UDCON15 Minor(V3) 0.823 124.155 150.843 270.000 UDCON15
C3-15x18
Column Design Chapter 06
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]
Column Design Chapter 06
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
Column Design Chapter 06
Page 44
Column Design Chapter 06
Page 45
Column Design Chapter 06
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
Footing Design Chapter 07
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
Footing Design Chapter 07
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)
Footing Design Chapter 07
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
Footing Design Chapter 07
Page 52
= 0.85 3
60 [1−√(1 −
2×34
0.85×3)] ×12× 15
= 0.135 𝑖𝑛2
But not less than, 200
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
But not less than, 200
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.
7.2.5 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
Footing Design Chapter 07
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
But not less than, 200
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.
Same as another transverse beam.
Fig: Plan view of combined footing
Footing Design Chapter 07
Page 54
Fig: Longitudinal section of footing
Fig: Footing Layout
Footing Design Chapter 07
Page 55
Chapter 08
Stair Design
Page 56
ETABS Concrete Design
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
ETABS v9.7.4 - File:Etabs_Capstone - Kip-in Units
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
Stair Design Chapter 08
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
8.1.3 Moment capacity check:
𝑎 =(𝐴′𝑠 − 𝐴𝑠)𝑓𝑦
0.85𝑓′𝑐𝑏
=(3 ∗ 0.79 − 2 ∗ 0.60) ∗ 60
0.85 ∗ 3 ∗ 10
= 2.75
∅ = 0.9 [from ETABS]
∅𝑀𝑛 = ∅(𝐴′𝑆 − 𝐴𝑠)𝑓𝑦 (𝑑 −𝑎
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
8.1.4 Stirrup check:
Vu = 25.38 kip [ETABS]
∅𝑣𝑐 = ∅2√𝑓′𝑐 ∗ 𝑏𝑑
= 0.85 ∗ 2 ∗ √3000*10*10.5
= 9776.85 lb
= 9.78 kip
𝑣𝑠 =𝑣𝑢 − ∅𝑣𝑐
∅
=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"]
Stair Design Chapter 08
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
Design of Underground Water Reservoir Tank
= 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
Design of Underground Water Reservoir Tank
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
Design of Underground Water Reservoir Tank
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
Ca, neg 0.95 Cb, neg
0.050
0.041
0.072
0.055
0.045
0.079 0.075
0.067
0.038
0.056
0.065
0.029
Ca, neg 0.90 Cb, neg
0.055
0.037
0.070
0.060
0.040
0.080 0.079
0.062
0.043
0.052
0.068
0.025
Ca, neg 0.85 Cb, neg
0.060
0.031
0.065
0.066
0.034
0.082 0.083
0.057
0.049
0.046
0.072
0.021
Ca, neg 0.80 Cb, neg
0.065
0.027
0.061
0.071
0.029
0.083 0.086
0.051
0.055
0.041
0.075
0.017
Ca, neg 0.75 Cb, neg
0.069
0.022
0.056
0.076
0.024
0.085 0.088
0.044
0.061
0.036
0.078
0.014
Ca, neg 0.70 Cb, neg
0.074
0.017
0.050
0.081
0.019
0.086 0.091
0.038
0.068
0.029
0.081
0.011
Ca, neg 0.65 Cb, neg
0.077
0.014
0.043
0.085
0.015
0.087 0.093
0.031
0.074
0.024
0.083
0.008
Ca, neg 0.60 Cb, neg
0.081
0.010
0.035
0.089
0.011
0.088 0.095
0.024
0.080
0.018
0.085
0.006
Ca, neg 0.55 Cb, neg
0.084
0.007
0.028
0.092
0.008
0.089 0.096
0.019
0.085
0.014
0.086
0.005
Ca, neg 0.50 Cb, neg
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
Page 84