Expeditious Design of Post-Tensioned
Floors and Beams Using Strip Method
Simple Frame and Equivalent Frame Approaches
- Featuring -
ADAPT-PT
®
ADAPT Corporation | Redwood City, CA, USA
ADAPT Latin America | Miami, FL, USA
ADAPT International Pvt. Ltd. | Kolkata, India
ADAPT Europe | Perugia, Italy
Dr. Florian Aalami
www.adaptsoft.com
April 2013
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© Copyright 2013 ADAPT Corporation all rights reserved
Agenda
Post-Tensioned Slab Design using Equivalent Frame Method
• Applicable Project Types
• Review of Design Process
• When to use 2D Strip Approach
• Design Example using ADAPT-PT
2
Complete Solution for Slabs & Beams
Column supported two-way flat slab systems
3
Complete Solution for Slabs & Beams
One-way beam and slab design
4
Complete Solution for Slabs & Beams
Beam frames and grids
5
Review of Design Approach
Typical layout of
column supported
floor system
COLUMN
SLAB
OPENING
SLAB
EDGE
BEAM
Y
X
6
Review of Design Approach
A
1st Step:
Determine
support lines
B
Support line
C
D
E
F
Y
X
G
7
Review of Design Approach
2
1
2nd Step:
Determine
tributaries and
create
“design strips”
3
A
B
C
D
E
F
Y
X
8
G
4
5
Review of Design Approach
3rd Step:
Determine
design sections
A
Sections for
strips B & E
shown
C
1
2
Y
DESIGN
SECTION
3
4
5
B
D
E
F
X
9
Review of Design Approach
4th Step:
Design each
section to provide
adequate capacity
and meet code
compliance
1
2
Y
DESIGN
SECTION
A
B
C
D
E
F
10
X
3
4
5
Review of Design Approach
2
1
5th Step:
Design other
direction of slab
3
4
5
A
B
C
D
E
F
Y
X
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Key Advantages of 2D Strip Method
• Easy to learn and use
• Quickly produces preliminary designs
• Produces optimized PT designs for each strip
• Great learning tool if new to post-tensioning
12
Strip Method Approach to Design
1
2
9
3
10
4
10
5
0.8
9.2
If using ADAPT-PT, develop
and model idealized design
strips
B
(a) DESIGN STRIP IN PROTOTYPE
1
9
10
10.6
10.5
2
3
4
5
0.8
B
(b) STRAIGHTENED DESIGN STRIP
IDEALIZED
B
ACTUAL
(c) IDEALIZED TRIBUTARY FOR DESIGN
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Traditional Design of 1-Way Systems
Beam frame
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One-way slab frame
The parking structure is broken down into typical beam and one-way
slab frames. A beam frame can span several parking modules.
Traditional Design of 1-Way Systems
Start ADAPT-PT modeling process by selecting appropriate structural
system.
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Traditional Design of 1-Way Systems
Use geometry table to easily model your design frame.
Design strip for a beam
spanning 2 parking modules
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Traditional Design of 1-Way Systems
Each design strip is designed to meet strength and service
requirements of the code.
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Traditional Design of 1-Way Systems
Amount of post-tensioning and profile are determined as well as any
additionally required flexural and shear reinforcement.
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PT Integration with Modeler
Leverage existing project information to save time modeling
Import
Import Geometry & Loading from Existing Models
•Revit® Structure
•AutoCAD®
•ETABS
AutoCAD Information
Intelligent Revit Structure Models
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Model Floor System in Modeler
Create true 3D slab model
Import
Geometry
& Loading
Models
•Revit® Structure
•AutoCAD®
•ETABS®
Model
ADAPTModeler
ADAPTTrue 3D
Modeler
Concrete
True 3D
Modeling
Concrete
Environment
Modeling
Environment
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True 3D Model of Slab System or
Entire Structure in ADAPT
Generate Design Strips
Generate design strips in Modeler
Import
Geometry
& Loading
Models
•Revit® Structure
•AutoCAD®
•Robot
•ETABS®
Model
Define Design Strips
ADAPTModeler
ADAPTModeler
Define Design Strips
True 3D
Concrete
Modeling
Environment
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Design Strips in PT
Carry out detailed analysis and design of strip in ADAPT-PT
Import
Geometry
& Loading
Models
Model
ADAPTModeler
ADAPTModeler
Export Strips to PT
ADAPT-PT
Design Strips in PT
Define Design Strips
•Revit®
Structure
•AutoCAD®
•Robot
•ETABS®
Define Design Strips
True 3D
Concrete
Modeling
Environment
All geometry and loading
information is transferred
to PT
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www.adaptsoft.com
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