Company
- Overview
- Mission
- Outreach
- History
- People
- Anke Dzikonski
- Antonio R. Mencarini
- Cary E. Ronan, PE, GE
- Chris R. Hundemer, PG, CEG, CHG
- Christopher Glenn, PE, LEED GA
- David G. Dixon, PG
- Dean H. Iwasa, PE, GE
- Dorinda C. Shipman, PG, CHG
- Frank L. Rollo, PE, GE
- Grover S. Buhr, PG
- Hadi J. Yap, PhD, PE, GE
- Haze Rodgers, PE, GE
- Jeffrey F. Ludlow, PG
- John Gouchon, PE, GE
- Joshua D. Graber, REA I
- Julie D. Frankel
- Kristen Lease, EIT, LEED AP
- Lori A. Simpson, PE, GE
- Maria G. Flessas, PE, GE
- Patrick B. Hubbard, PG, CEG
- Peter J. Cusack, REA
- Philip T. Tringale, PhD, PE
- Philip G. Smith, RG, CPGS, REA II
- Ramin Golesorkhi, PhD, PE, GE
- Richard D. Rodgers, PE, GE
- Scott A. Walker, PE, GE
- Serena T. Jang, PE, GE
- Sigrida Reinis, PhD, PE
People
Hadi J. Yap, PhD, PE, GE, Principal Engineer
- PhD in Geotechnical Engineering, UC Berkeley
- MEng in Geotechnical Engineering, Asian Institute of Technology, Bangkok Thailand
- Ir. in Civil Engineering, Universitas Indonesia, Jakarta
- Professional Civil Engineer (PE) California
- Geotechnical Engineer (GE) California
- Hire Date 03-16-98
- Phone: 415-955-9040 ext. 232
- Email: hjyap@treadwellrollo.com
After more than 35 years, I still like the field--no two projects are alike. 
Hadi was initially drawn into geotechnical engineering when chosen to represent his company in an international joint venture with a company specializing in deep foundation construction. Since then he has amassed over three decades of experience in managing geotechnical investigation and construction observation services.
Hadi's projects include high-rise buildings, medical facilities, schools and colleges, earth dams, and waterfront structures. In addition, Hadi has worked with seismic retrofitting of bridges and historical buildings. He has taught geotechnical courses at several universities and performed research on engineering properties of soil, stabilization of soil with additives, pile capacities and hydraulic fracturing.
His practice has included projects throughout the Pacific Rim and Guam. Whether working internationally or on Treadwell& Rollo's projects across the country, one value remains essential: "I like clients to know that I am looking after their interests."
Featured Projects:
- Bacich Elementary School
- View Project »
- Cabrillo College
- View Project »
- Cathedral of Christ the Light
- View Project »
- Oakland Uptown Development
- View Project »