Unit 4: San Francisco-Oakland Bay Bridge Earthquake (1989) | STEM Disaster

Investigate the famous infrastructure failure during the 1989 Loma Prieta Earthquake with this complete 6-page printable STEM Case Study Packet! Designed specifically for middle and high school classrooms, this unit provides a deep, informative look at the 1989 San Francisco-Oakland Bay Bridge Deck Collapse, seismic ground acceleration, out-of-phase truss movement, anchor bolt shear failure, expansion joint bearing seat lengths, and seismic retrofitting physics. What’s Included in this 6-Page Deep-Dive Packet: Page 1: Historical Case Study & Technical Breakdown – Full historical narrative of the October 17, 1989 disaster during the World Series, double-deck cantilever truss design, seismic S-wave propagation, anchor bolt shear failure, bearing seat overhang limits, and comprehension check questions. Page 2: Day in the Life Scenario Challenge – Students step into the shoes of a Lead Forensic Seismic Engineer on October 18, 1989, analyzing real-time earthquake telemetry, Peak Ground Acceleration (PGA) logs, and bridge span displacement diagnostics. Page 3: Hands-On Unplugged Simulation & Applied Math – Simple step-by-step math calculations comparing anchor bolt shear resistance capacity (lbs) vs. peak lateral seismic force, expansion joint seat lengths (inches) vs. differential ground displacement, and safety factor ratios. Page 4: Engineering Ethics & Workplace Dilemma – Deferring costly retrofits vs. earthquake probability: analyzing pre-1989 seismic inspection warnings, balancing multi-million dollar retrofit budgets, critical transit dependency, and public infrastructure prioritization. Page 5: Redesign Brief & Innovation Lab – Creative blueprinting assignment where students design "Bay Bridge Seismic Retrofit V-2," featuring longitudinal tie-bars, hydraulic friction dampers, wide 30-inch seat extension ledges, and real-time seismic accelerometers. Page 6: Teacher Answer Key & Scoring Rubric – Complete answer key for all questions and math problems, plus a 10-point grading rubric on Page 6 for evaluating student work on Page 5. Teacher Benefits: 100% Unplugged & Copy-Paste Friendly – Clean text layout with zero dark background boxes, code block syntax, or special math symbols for seamless editing in Word, Google Docs, or Canva. Multi-Day Classroom Value – Covers 3 to 5 full class periods; perfect for Physics, Physical Science, Earth Science, Civil Engineering, Architecture, CTE electives, or emergency sub plans. Highly Engaging Content – Combines real earthquake physics, structural shear math, forensic bridge inspection, state transportation policy, and seismic engineering redesign!