Upload
lybao
View
213
Download
1
Embed Size (px)
Citation preview
DESIGN OF A MODERN HIGH-RISE BUILDING
IN ABU-DHABI
United Arab Emirates University
Faculty of Engineering
Department of Civil and Environmental Engineering
Graduation Project II
Fall 2010
Thursday 13 January 2010
Student Name ID Number
Abdulrahman Abdulla Alili 200409918
Mohammed Amer Al-Ameri 200416269
Wadah Abdulla Ahmed 200540613
Amr Ezzat Abdel-Havez
200540677
Advisor : Dr. Aman Mwafy
Examination Committee:
Dr. Hany Maximos (Faculty)
Dr. Amr Sweedan (Dept.)
Dr. Bilal El-Ariss (Dept.)
Objectives
� The Graduation Project is divided into two main phases, namely
GPI and GPII. The three-dimensional (3D) analytical modeling of
the 60-story building, load calculations and verifications of the
analytical model were performed in GPI. Tasks and results of this
phase are briefly presented in this report.
� The second phase of the project focus on designing different
structural members of the high-rise building such as floor slabs,
beams, columns, shear walls and foundations using latest analysis
software and modern design codes.
Original Building
Building After Modifications
Design process
Requirements Specifications Conseptual Design
Embodiment Design
(Simulation Model)
Detailed Design
Specification:
Building should be design according to:
–ACI 318-05 Code.
–IBC 2009/ASCE 7-05 for calculating the wind loads.
Structural Analysis programs:
–CSI ETABS
–CSI SAFE
–PROKON
Requirement:
–Plan area: 1750.2 m2
–Total number of stories: 60
– Typical Story height: 3.5 m
–Use of the building: residential building
–Used materials: normal and high strength
material and reinforcing steel
Summary of GPI
� Geometric and Load Modeling
� Structural elements modeling (beams, slabs etc..)
� Load modeling
� Hand Calculations
� Actions and deformations
� Preliminary Cost Estimate
Summary of GPI
0
5000
10000
15000
20000
25000
30000
EarthquakeLoadWind Load E-W
Hand Calculation ETABS Results
0
200000
400000
600000
800000
1000000
1200000
Dead Load
Live Load
Hand ETABS Results
GPII Tasks
� Verified three dimensional analytical model of a typical 60-story building,
representing the modern tall buildings in the UAE.
� Design different structural elements, including the complete design of suitable
floor slab systems, such as solid slabs and flat slabs, at different story levels of
the high-rise building using the SAFE and PROKON programs.
� Optimized design of shear walls using the latest version of the ETABS program
with different load combinations and different cross section sizes and
reinforcement ratios to arrive at the most cost-effective design.
� Design of columns and different types of beams.
� Design of stairs and the piles foundation system.
� Final Cost Estimates.
Design of slab systems
Flat Slab
Hollow Block Slab Solid Slab
Diaphragms and slabs can be defined as a structural system that resist, collect and
distribute the lateral forces, either earthquake or wind, in the horizontal planes of a structure
then transmit them to the vertical bearing elements (shear walls, frames) then to the
foundation and the ground.
In GPII we have designed three types of slab systems
1- Flat Slab
2- Hollow Block Slab
3- Solid Slab
Design of Hollow Block slabs
Design as a T-Section
Hollow Block slabs � Different alternatives of the slab dimensions are considered.
� We started with a depth equals to 250 mm, which led to a deflection that
exceeds the
maximum allowed value.
� To overcome this issue, we increased the depth of the slab to 350 mm by having
two
layers of blocks each has 150 mm height, which produced safe deflection
Increasing the width of ribs
Increasing the depth & number of blocks
Increasing of the reinforcement
Solid Slabs
Wu=1.2WD+ 1.6WL == 16.98 kN/m2
Mu = 13.262 kN.m/m
Rn=[Mu/ ( = 2.62 � ρ = 0.0065
As= ρbd=487.5 mm2 � use 7 bars #10
Flat slabs Exporting three slabs:
� The following three slabs are exported from ETABS to SAFE:
� Ground story slab.
� 17th story slab.
� 37th story slab.
� Two critical load combinations are selected to extract results from SAFE,
1.4 SDL+1.4 O.W+ L.L+ 1.4 EQX) a
1.4 SDL+1.4 O.W+ L.L+ 1.4 EQY).
�The design process of flat slabs is started by
determining the most optimum thickness of the slab.
�The optimum thickness can be determined by
selecting the slab thickness and verifying the
deflection
Slab Optimum thickness �∆L < L/360
�∆L + ∆add < L/360
�∆add = λ∆ * ∆D
�λ∆ = ξ / 1+ 50 ρ
�ρ` = As`/ bd
Ground story slab thickness equals to 200 mm:
L/360 = 22.2 mm
L/240 = 33.33 mm
d = 200 – 25 = 175 mm
ρ ̀= As /̀ bd = 0.003686
λ∆ = ξ / 1+ 50 ρ ̀= 1.6887
where � ξ = 2
∆L < L/360 � 5.22 < 22.22 � O.K
∆D = 13.5 + 13 = 26.5
∆add = λ∆ * ∆D = 44.71
∆L+ ∆add < L/360 � 49.93 > 33.33 �
unsafe, we have to increase the thickness.
Design of flat slabs
Strip # Direction Strip width (m) Strip type
S1 x X direction 1 Column strip
S2 y Y direction 4 Middle strip
S3 y Y direction 4 Middle strip
�Three strips are defined for each slab, two middle strips and one column
strip, as shown below.
�The defined strips are used to calculate the maximum bending moment, as
shown in Figures
Design of flat slabs � Example :Ground story
� After extracting the maximum positive and negative moment, each is divided by the strip width to get the bending moment per unit length and calculate the corresponding reinforcement
Strip No. +M -M +M/width -M/width
S1x 123.3 240.9 123.3 240.9
S2y 229.13 600.3 57.28 150.1
S3y 298.78 196.9 74.695 49.2
Strip No. +M/width ρ As = ρbd Mesh top & bot.
S1x 123.3 0.00457 1188.2 6Ф16
Strip No. -M/width As = ρbd Amesh As - Amesh Additional Reinf.
S1x 240.9 2410 1188.2 1221.8 6Ф16
S2y 150.1 1457.64 1188.2 269.44 4Ф12
S3y 49.2 463.46 1188.2 ---- ----
Strip No. -M/width As = ρbd Amesh
As -
Amesh Additional Reinf.
S1x 240.9 2410 1188.2 1221.8 6Ф16
S2y 150.1 1457.64 1188.2 269.44 4Ф12
S3y 49.2 463.46 1188.2 ---- ----
Check of Punching Shear
12
')2(
fc
b
d
o
s
+α bod
3
'fc bod
6
')
21(
fc
cβ+ bod Vc1 =
Vc2 =
Vc3 =
Vu = Ф Vc + Ф Vs
Element Vc (KN) f Vc (KN) Vu (KN) fVu (KN) Decision
Col-1 595.9 446 161.88 242.82 Safe
Col-2 1115.94 836.96 275.08 357.6 Safe
Col-3 2147.66 1610.745 151.8 197.34 Safe
Best Alternative
Flat Slabs
Hollow Block Slabs
Decision Based
on
Efficiency/
Construction
Cost
0.00
10.00
20.00
30.00
40.00
50.00
60.00
Floor slabs cost Hollow block slab
Cost in Millions AED
- The choice of the slab system for the 60-
stor building is based on the cost and
performance
- The hollow block slab system is more
expensive than flat slabs. Moreover, flat
slabs are much easier in construction, and
therefore the flat slabs are selected.
Stairs
Wu = 16.08kN/m2
Wu X 0.3 load of each stair = 16.08 X 0.3 = 4.824 kN/m
(M max)= (Wu x L2)/2= (4.824 x 1.452) /2 = 5.07 kN .m
.
STEP 1: Determine steel ratio (ρ)
Rn = [Mu/ (= (5.07*106)/ (0.9*300*(195)2) = 0.49
ρ = (1- ) = 0.00117
ρmin = 0.003521
STEP 2: Determine As
As= ρ×b×d = 0.003521*300*195= 206 mm2
[ use 3 bars#10]
Stairs
�Design of stairs using hand calculations
Stairs
Reinforcement details of stairs
3#10 /step
3#10 /step
�Reinforcement distribution
Beams �Design of hidden beam
�Design of edge beam
�Design of connecting beam B1
Connecting beams
Beams
(M max) = (Wu x L2)/8 =168.44 (KN.m)
STEP 1: Determine steel ratio (ρ)
Rn= = = 0.975
ρ = (1- ) = 0.002361
ρmin = 0.003521 from Eqn. 13
ρmax= 0.0216 from
Then ρmin ≤ ρ ≤ ρmax � use ρmin
STEP 2: Determine As
d= Beam height – cover = 450 -50= 400 mm
As = ρ × b × d = 0.003521 × 1200 × 400= 1690.1 mm2
From Ref [11] , Table B.4 � use 9 bars # 16
From Ref [11], Table B.5 � One layer
Beam cross section
�Design of hidden beam using hand calculations
Beams
Bending moment diagram of the hidden beam
Beam deflection
�Design of hidden beam using Prokon
Beams
Slab Load:
Dead load from slab = 48.03 kN/m
Live load from slab = 8.5 kN/m
Beam own weight
hb= 620 mm
O.W Beam= bw× hb× γ c = ((0.25×0.24) + (0.81 × 0.38)) × (25) = 9.195 kN/m)
Wall own weight
O.W wall = bw× hw× γ = 0.25 × 2.88 × 10 = 7.2 (KN/m)
Effective Length
bw + 6t= 0.25+ (6×0.38)=2.53
Effective width (bE)= Smaller of bw + L / 12=0.25 +(6.7/12)=0.81m
bw + b0= 0.25+ 4= 4.25 m
Then, Effective length (bE)= 0.81 m = 810 mm
Edge beam cross section
�Design of edge beam using hand calculations
Beams
Long-term deflection
Moment x-x
�Design of edge beam using Prokon
Reinforcement distribution
Beams �Reinforcement distribution
Beams
� Check if it’s coupling or conventional beams:
�Design of connecting beams
Length divided by
height
Greater than 2
From ACI code
Conventional beams
� [3/1]= 3 greater than 2 �.ok
Beams
Input data in prokon
�Design of connecting beams using ETAB’s & Prokon
Beams
Level Beams No. Flange Width Bending Moment Shear Force
ground
story levels
B1_1 750mm M=1270.42 KN.m V=865.2 (KN)
Reinforcement 8 T 25 4 T 8@ 120 mm
B1_2 625mm M=1660.9 KN.m V= 1047.6 (KN)
Reinforcement 10 T 25 4 T 10 @ 150 mm
B1_3 625mm M=1537.34 KN.m V= 1072.71 (KN)
Reinforcement 9 T 25 4 T 10@ 120 mm
17th story
levels
B2_1 750mm M=763.82 KN.m V= 620.4 (KN)
Reinforcement 5 T 25 4 T 8@ 150 mm
B2_2 625mm M=895.1 KN.m V= 716.71 (KN)
Reinforcement 6 T 25 4 T 8@ 120 mm
B2_3 625mm M=767.92 KN.m V= 619.9 (KN)
Reinforcement 5 T 25 4 T 8@ 150 mm
36th story
levels
B3_1 750mm M=760.1 KN.m V= 630.37 (KN)
Reinforcement 5 T 25 4 T 8@ 150 mm
B3_2 625mm M=820.9 KN.m V= 637.1 (KN)
Reinforcement 5 T 25 4 T 8@ 150 mm
B3_3 625mm M=679.5 KN.m V= 564.4 (KN)
Reinforcement 4 T 25 4 T 8@ 200 mm
Data outcome form Prokon & ETAB’S
�Design of connecting beams using ETAB’s & Prokon
Shear Walls
�Design shear walls using ETAB’s
Selected shear walls
Shear Walls
o Define pier section.
o Pier section data.
o Section designer.
o Assign pier section.
o Assign general Reinforcing pier section.
o Start design of section.
�Design process
Shear Walls
� The D/C ratio indicates the demand over capacity:
◦ D/C Ratio less than 1 � section is safe in flexure
◦ D/C Ratio greater than 1� Section is unsafe
�General reinforcing Pier Section
Shear Walls
� As(min) = (0.25/100) × Ag
�Optimization
Level Wall Reinforcement
Layout (1,2 and3)
P3S mm167@12#6
P2SS mm167@12#6
P1SS mm167@12#6
P4S mm167@12#6
P5 mm167@12#6
P6 mm200@12#5
P7 mm167@16#6
Columns
Columns name Col(1-20) Col(2-20) Col(2-40)
No. of columns 8 4 4
Columns dimension (1000x300) (1500x400) (1500x300)
�Design columns using ETAB’s
Columns
�Columns reinforcement detail
Columns
� If columns un-safe:
�Check safety of columns
Increase columns dimension
Increase concrete strength
Design of Foundation
among the raft area.
�Using Safe program 709 piles have been distributed
among the raft area.
Foundation Results
�Point loads representation due to applied loads.
Foundation Results
�Deformed shape.
Foundation Results
Strip # 1 in X-direction Strip # 2 in Y-direction Strip # 3 in Y-direction
Foundation Reinforcement
�Reinforcement detailing for the raft foundation
�Beams Beams (cost) = width × length × depth × number of stories × cost of one m3
�Columns Columns (cost) = width × length × height × number of stories × cost of one m3
Cost Estimate
Cost Estimate
�Shear Walls Shear walls (cost) = thickness × length × height × number of stories × cost of one m3
�Floor slab Flat slab (cost) =thickness × net area × cost of one m3× number of stories
�Stairs
Stairs (cost) = Area Stairs × thickness × Factor (1.2)× number of stories × cost of one
m3
= [(3 m ×7 m)×0.23 m×1.2× 60 stories ×2500 (Dhs/ m3)]×2= 1,738,800 AED
Cost Estimate
�Excavation Excavations (cost) = Depth × Area Raft × cost of one m3
= 11 m × 1750.2 m2 × 50 (Dhs/m3) = 962,610 AED
�Plain Concrete Concrete Plan(cost)= Area Raft × Thickness × Cost of one m3
= (1750.2) m2 × 0.4 m × 700 (Dhs/ m3)= 490,056 AED
�Raft Foundation Raft foundation(cost)= Area Raft × Thickness × Cost of one m3
= (1750.2) m2 × 3.2 m× 2200 (Dhs/m3) = 12,321,408AED
�Pile Foundation Piles foundation (cost)= Number of piles × length of pile × Cost of one meter
= 709 piles × 25 m × 2800 (Dhs/m) = 49,630,000 AED
Foundations
170,969,819
AED
Cost Estimate
0
10
20
30
40
50
60
70
Cost
in M
illi
on (
AE
D)
�Final cost estimate of structural system
Project Management
Outcomes and Deliverable
�Verified three dimensional analytical model for a typical
60-story building, representing the modern tall buildings in
Dubai and Abu Dhabi.
�Design different structural elements and establish full
design of suitable floor slab systems, such as solid slabs and
flat slabs, at different story levels of the high-rise building
using SAFE and PROKON programs.
�Design of columns and different types of beams such as
conventional.
Conclusion
�The analytical model and modern design provisions
have been employed in the second phase of the project
(GPII) to fully design different structural members of the
60-story high-rise building.
�Work in a group and write technical reports.