Protecting PT Parking Structures: Evaluation, Repair & Corrosion Mitigation Strategies

Post-tensioned (PT) concrete reinforcement systems are widely used in parking structures due to their structural efficiency, reduced slab thickness, and long-span capabilities. However, over time, these systems may deteriorate due to environmental exposure, construction deficiencies, or inadequate maintenance. This can lead to corrosion of post-tensioning tendons, cracking, and even structural distress. In order to mitigate these risks, the resolution process requires implementing a targeted maintenance program and early intervention to preserve the structural integrity and functionality of PT systems.

This recording of our live webinar session reviews different approaches to inspection, evaluation, replacing and repairing post-tensioned reinforcement in concrete parking structures.

To attend live webinars like this one and receive NCSEA-approved PDH credits, check out the webinars page on our website to see what sessions we are currently hosting at https://www.wesavestructures.info/Web...



Timestamps:
0:00 Introduction
3:04 Presentation Outline
3:56 How to Evaluate the Corrosion Risk for Post-Tensioned Tendons
4:48 How to Plan to Test Post-Tensioned Concrete Reinforcement Systems
5:13 What to Look for When Evaluating a Post-Tensioned Reinforced Concrete
6:13 What Challenges Come with Post-Tensioned Reinforced Concrete
7:25 The Different Types of Post-Tensioned Tendons
8:23 What is the Concrete Preservation Process
11:26 What Features of Post-Tensioned Tendons Cause Deterioration in Concrete
12:31 What Visible Signs of Damage Look Like in Post-Tensioned Reinforced Concrete
13:07 Types of Non-Destructive Testing Methods for Concrete Structures
14:15 Types of Invasive Testing Methods for Concrete Structures
14:51 What to Look for When Visually Inspecting Post-Tensioned Reinforced Concrete
16:46 What Moisture Issues Look like in Post-Tensioned Reinforced Concrete
17:21 What is Post-Tensioned Tendon Profile Analysis
18:00 What is Punching Shear
18:50 What Does Cracking From Overload or Loss of Post-Tension Force Look Like
19:21 How to Excavate and Evaluate Broken Post-Tensioned Tendons
21:10 Effective Testing Procedures for Post-Tensioned Reinforcement Systems
22:35 How to Use Ground Penetrating Radar to Locate PT Tendons
23:17 Excavating Post-Tensioned Tendons
24:22 What is the Screwdriver Penetration Test
25:17 What to Look for When Excavating PT Tendons
26:03 What to Look for When Excavating Anchor Pockets
27:01 When to Utilize Shoring in the Evaluation Process
27:23 What is Corrosion Potential Testing
29:57 What is Moisture Testing
31:09 What is Lift Off Testing
31:20 What is Lateral Deflection Testing
31:55 When is a Corrosion Mitigation Strategy Possible in a PT Reinforcement System
33:54 How to Dry Post-Tensioned Tendons Using a Dry Air Generation System
35:30 What is Post-Tension Injection
36:22 PTI Approved Methods for Exposed Tendon Sheathing Repair
37:09 Non-Corrosive Causes of Broken PT Tendons
37:45 Methods to Repair Broken PT Tendons
39:51 How to Protect Against Corrosion in a Buttonhead System
40:30 How to Protect Against Corrosion of Anchors in a PT Reinforcement System
41:34 How to Use Surface-Applied CP to Mitigate Corrosion in a PT Reinforcement System
42:53 Presentation Summary and Conclusions
44:18 Extended Question Period Begins
44:39 Is There an Official Standardized Process for the Screwdriver Penetration Test
47:06 Is it Possible to Damage a PT Tendon Through the Screwdriver Penetration Test
47:40 How Viable is Corrosion Potential Testing in PT Reinforced Structures Since the Only Exposed Steel Should be in the Anchors
49:09 Can You Use Impressed Current Cathodic Protection (ICCP) Systems on PT Reinforcement Systems
49:58 What is Hydrogen Embrittlement
51:12 What is the Best Corrosion Mitigation Strategy for PT Reinforcement Systems
52:45 Is Ground Penetration Radar (GPR) an Effective Testing Method for PT Reinforcement Systems
54:45 Is There Any Benefit to Delaying the Cable Drying Process in the Repair
55:48 At What Level of Degradation Do PT Tendons Have to Be Replaced Rather Than Repaired
56:53 What is Better to Repair Tendon Splicing, Dog Bone Anchors or Grabb-it Cable Splices?
57:52 Is There a Way to Replace Tendons Without Excavation
58:50 What is the Best Water-proofing Solution for PT Reinforced Concrete
1:00:19 What is the Best Method for Sealing Cracks to Limit Water Intake
1:01:30 What Impact Does Excavating Concrete Have on Adjacent Tendons
1:03:21 How to Determine Where Water is Getting into Your Concrete
1:05:10 Who Should Be Responsible for Ensuring Aging Concrete Structures are Maintained
1:07:44 Closing