final presentation - group 2 (1)
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Prestressed Concrete (CE 5309)
Term Project
Group 2
Spring 2016
University of Texas at Arlington
PART 1
PRE-TENSIONED PRESTRESSED BRIDGE DESIGN
IH-35W Bridge 205
Design Information
Overall width of bridge = 53 ft; roadway width = 51 ft
Limit maximum Girder length to 120 ft
TxDOT T551 rail – 382 plf
Typical composite cast-in-place deck with 8” thick and f’c= 4 ksi, Ec = 3605 ksi
Girders with ultra-high concrete strength – f’ci = 20 ksi,
f’c = 30 ksi, Ec = 9872 ksi
PGSuper V 2.9.0.9
TxDOT 2013 Bridge Design Manual
Geometry
8 Number of spans
Exterior spans - 105 ft.
Interior spans - 115.06 ft.
Tx70 girders selected
Most economical
Least weight
Least number of girders
4 girders spaced at 16' on center
Design Parameters
PGSuper Model
Strand Layout, Span 8 Girder A
Section @ Mid-SpanSection @ Left-End Section @ ¼ Span
Shear Layout
Concrete Strength
Deck Properties and Overlay Weight
Design Results of Various Girders
Model Number
Girders
Strand Dia (in)
Weight of
Beam(kip/ft)
Number of strands (Exterior spans)
Number of strands (Interior spans)
Total Number
of Strands
Total weight of
girders (kips)
Total number
of girdersExternal
Girders
Internal
Girders
External
Girders
Internal
Girders
Tx 54 6 0.6 0.88 24 28 30 34 1496 38030.78 48
Tx 54 7 0.6 0.88 24 24 28 30 1572 44369.25 56
Tx 62 5 0.6 0.98 24 28 30 34 1236 35293.72 40
Tx 62 6 0.6 0.98 22 24 26 28 1264 42352.46 48
Tx 62 7 0.6 0.98 22 22 24 26 1376 49411.208 56
Tx 70 4 0.7 1.04 32 40 36 44 1248 29963.65 32
Tx 70 5 0.7 1.04 24 24 24 28 1032 37454.56 40
Tx 70 6 0.7 1.04 22 24 22 24 1120 44945.472 48
Final Design
Tx70, total 32 girders
1248 strands
No de-bonding used
Grade 270, Low-relaxation 0.7" strands
Additional mild steel reinforcement used
TxDot standard details used for shear design
f‘ci = 20 ksi, f‘c = 30 ksi
Distribution of L.L for span 8
• From hand calculation = 1.256
• Difference = 8.7%
Moment Capacity at Mid-spanExterior Girder – End Span
Comparison of Multiple Loads Moments And Moment Capacity
Comparison of Multiple Loads Shear And Shear Capacity
Multiple Loads Displacement
Ahmed, Haroon Rasheed
Girder Design (Tx 40 and 46)
Drawings,
PowerPoint Presentation
Bichewar, Namrata
Girder Design ( Tx 70)
Live Load Moment Distribution Factor
Emami Saleh, Arash (Team Leader)
General Model
Moment Calculations,
PowerPoint Presentation
Okagbare, Oghenekevwe Christabel (Team Leader)
Girder Design ( Tx 28 and Tx 34)
Drawings
Project Report
PowerPoint Presentation
Shaltoof, Mohammad Abed Mohammad
Girder Design( Tx 54 and 62)
Moment Calculations
PowerPoint Presentation
Distribution of Work
PART 2
POST-TENSIONED TWO-WAY SLAB DESIGN
Overall Second Level Plan
Design Parameters
Concrete Properties
Slab Thickness = 8 inches
F’c = 4,000 psi, Ec = 3605 ksi
Prestressed Steel Properties
½” dia. Grade 270 low-relaxation strands
Initial Prestress = 0.8 * fpu
Loading
Superimposed Dead Load = 20 psf
Superimposed Live Load = 40 psf
ACI 318-11 used as design code
Design Consideration
4 – span condition utilizing wall as an exterior support
Equivalent Frame Method
Software Inputs
Software Input
12’ floor to floor heights above & below
24” square columns
Exterior shear walls modeled to same width of design strip
Slab assumed to be fixed-fixed at boundary condition
Average Precompression range 125 psi to 300 psi
Percentage of Dead Load to balance 25% to 200%
Post-Tension Strand Cover: 1.5” top
2.0” bottom
Mild Reinforcement Cover: 1.0” top & bottom
Tributary Area
Tributary Area (Cont…)
Loading on the slab
ADAPT Rendering
Final Design Stresses
Max Tensile Stress = 0 x √(f’ci) < 3 x √(f’ci) OK
Max Compressive Stress = 0.164 x f’ci < 0.6 x f’ci OK
Number of tendons : 24 ( 6 – bands with 4 in each )
Final Design Stresses
Sustained Load Stresses
Total Load Stresses
Stress Diagram
-450
-400
-350
-300
-250
-200
-150
-100
-50
0
50
100
150
200
SPAN 1 SPAN 2 SPAN 3 SPAN 4
Stress DiagramsProject: "Term Project" / Load Case: SERVICE_1_Max_LL
+1.00 SW +0.30 LL_Max +1.00 SDL +0.30 XL +1.00 PT +0.00 HYP +0.00 LATTensile Stress Positive
Str
ess
[psi
]
Allowable Stresses Top
Tendon Profile
FINAL DESIGN: 15 – ½”, Grade 270 Low-Relaxation strands
Mild Steel Profile
Tendon layout24 strands – 4/band
Shear stud layout
Distribution of Work
Al Mutar, Sudad Saeed
• Model,
• Hand Calculations
• Project Report
• Presentation
Kadam, Kshitij Chandrakant
• Model
• Hand Calculations
• Project Report
• Presentation
Mazumder, Md Shahadat Hossain –
• Building Model and Bridge General Model
• Shop Drawings
• Project Report
• Presentation
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