📋 Case Study

High-Rise Residential Tower in San Francisco

Meeting stringent SDC D requirements while minimizing column sizes in tight urban footprint

🏗️ Project Overview

32-story reinforced concrete tower with podium parking and seismic base isolation

🎯 Challenge

Meeting stringent SDC D requirements while minimizing column sizes in tight urban footprint

🔧 Design Approach

Special moment-resisting frames with ductile detailing per ACI 21.4; performance-based pushover analysis

📐 Design Diagram

AI-generated project design illustration

📐 Key Calculations

Column Plastic Hinge Rotation Capacity

θp = 0.02 rad (ACI 21.4.4.2)

Result: 0.022 rad

Ensures life safety under MCE event

Beam-Column Strength Ratio (ΣMnc/ΣMnb)

≥ 1.2

Result: 1.38

Prevents soft-story collapse mechanism

📊 Results

Achieved drift < 1.5% under DBE; 12% reduction in core column volume vs conventional design

💡 Lessons Learned

• •Ductile detailing must be verified at connection zones—not just member level
• •Pushover modeling requires calibrated hinge properties from lab-tested specimens

✅ Key Takeaways

• 1Ductile detailing must be verified at connection zones—not just member level
• 2Pushover modeling requires calibrated hinge properties from lab-tested specimens