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[PDF] The Complete Guide to Prestressing Ebook

Written by midasBridge Team | August 5, 2021

 


Confused about how to model Prestressing?

 

Please fill out the Download Section (Click here) below the Comment Section to download the PDF Files!

 

 

Prestressing concrete provides internal compression, which counteracts the tension caused by loads coming onto it. It can be internal or external, pre-tensioned or post-tensioned, straight or curved. But the important thing is the application of appropriate prestressing load in the proper location along the length of the girder/beam.

 

 

Through this eBook, you can understand different tendons, and various profile generation techniques and appropriately predict the various long-term and immediate losses in midas civil. Examples are used for the calculation and verification of the losses in midas civil. Some key tips/notes are provided along the way for better modeling.

 

 

Key Points

 

1. What is prestressing?

 

Prestressing is the process by which the concrete element is compressed using wires, strands, etc. Concrete is a compression resisting material and its tension resisting capacity is very poor. So, the ultimate purpose of prestressing is that most of the concrete remains in compression even after the load is applied.

 

This can be achieved via 3 methods:

    01-1. Internal Pre-tension
    01-2. Internal Post-tension
    01-3. External Post-tension

 

2. Losses in Tendons

They are mainly divided into 2 categories: Immediate loss and long-term loss.

 

3. How to Apply Prestressing in MIDAS CIVIL?

 

03-1. Tendon Property

             03-1-1. Total Tendon Area

             03-1-2. Duct Diameter

             03-1-3. Strand Diameter

             03-1-4. Relaxation Coefficient

             03-1-5. Curvature Friction Factor

             03-1-6. Wobble Friction Factor

             03-1-7. External Cable Moment Magnifier

 

03-2. Tendon Property

            03-2-1. Typical Tendon

            03-2-2. Debonded Length

            03-2-3. Reference Axis

            03-2-4. Profile Insertion Point 

            03-2-5. Point of Symmetry

            03-2-6. X-axis Direction

 

03-3. Tendon Prestress

  

4. Methods of Defining a Tendon Profile

 

04-1. Simple Beam

04-2. Curved Tendon Profile

04-3. Beam in X-Y Plane

04-4. PSC Section with Inclined Web

04-5. Copying of Tendon

  

5. Loss Verification

 

05-1. Immediate Loss

              05-1-1. Elastic Shortening Loss

              05-1-2. Anchorage Slip

              05-1-3. Friction Loss

              05-1-4. Creep & Shrinkage Loss

              05-1-5. Relaxation Loss

 

6. Common Mistakes While Modeling Tendons

    Common mistakes while modeling the tendon in midas Civil occur while defining the tendon profile.

 

 

Please fill out the Download Section (Click here) below the Comment Section to download the PDF Files!