Case Study: QC Failures in Precast Concrete Panel Installation on Seattle Viaduct Replacement (Washington, 2019)
Project Overview
• Name: Alaskan Way Viaduct Replacement
• Location: Seattle, Washington
• Year: 2019
• Project Size: $3.3 billion
• Scope: Precast concrete panel installation for elevated highway segments
• Lead Agencies/Contractors: Washington State Department of Transportation (WSDOT) /
Category of the Issue, Problem, or Challenge
• Quality Control
• Materials
• Structural
Summary of the Issue, Problem, or Challenge
Misalignment and surface damage to precast panels during installation caused rework and project delays.
Root Cause Analysis
- Insufficient pre-installation inspection and handling protocols.
- Lack of coordination between lifting crews and installation teams.
- Inadequate training on panel handling to prevent damage.
- Poor documentation of QC checks during installation.
Impacts Due to the Issue, Problem, or Challenge
- Delay of 4 months due to rework and replacement of damaged panels.
- Increased costs for repairs, labor, and schedule impacts.
- Risk of structural integrity issues if damaged panels were accepted.
Corrective Actions Taken
- Developed comprehensive handling and installation procedures for precast panels.
- Enhanced coordination between lifting and installation crews.
- Provided targeted training on safe handling and damage prevention.
- Increased inspection and documentation during installation phases.
Lessons Learned
- Careful handling and inspection prevent costly damage to precast elements.
- Clear communication between crews is essential for quality installation.
- Documentation supports accountability and corrective action.
Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation
- Are handling and installation procedures clearly defined and followed?
- Is there effective coordination between all involved crews?
- Are inspection results documented thoroughly?