Case Study: Insufficient QC in Steel Fabrication on Los Angeles Bridge Project (California, 2018)

Project Overview
• Name: Los Angeles River Bridge Replacement
• Location: Los Angeles, California
• Year: 2018
• Project Size: $700 million
• Scope: Replacement of steel bridge spans over the Los Angeles River
• Lead Agencies/Contractors: Caltrans /

Category of the Issue, Problem, or Challenge
• Quality Control
• Fabrication
• Structural

Summary of the Issue, Problem, or Challenge
Fabricated steel components were found with dimensional inaccuracies and welding defects during erection, leading to delays and costly corrections.

Root Cause Analysis

• Fabricator’s quality management system failed to catch dimensional errors.
• Welding inspections were inconsistent and lacked thorough documentation.
• Insufficient supplier oversight and coordination.
• Limited communication between fabricators and field erection teams.

Impacts Due to the Issue, Problem, or Challenge

• Delay of 4 months due to rework and re-fabrication of defective parts.
• Additional costs for inspection, correction, and schedule extension.
• Potential risk to structural integrity if defects went uncorrected.

Corrective Actions Taken

1. Strengthened fabricator quality management and inspection regimes.
2. Instituted full documentation and traceability for welding and dimensional checks.
3. Improved communication and coordination protocols between shop and field teams.
4. Conducted joint training sessions for fabricators and erection crews.

Lessons Learned

• Fabrication QC directly affects field installation efficiency.
• Detailed documentation and traceability support defect detection.
• Coordination between fabrication and construction teams is essential.

Audit & Prevention: Project Control Questions to Ask on Future Projects to Help Control the Situation

• Are fabricators’ QC systems robust and verified?
• Is welding and dimensional inspection fully documented?
• Are fabrication and erection teams coordinated effectively?