What Is Seismic Design for Bridges (AASHTO)?
Bridges (the AASHTO's — the SGS's; the 9th) are designed for (the seismic — the SDC's; the A's) via (the 1.0's — the R's; the ductile) and (the 2%'s — the drift's; the 0.04's). The design: the SDC's (the A's — the 4's; the 0.15's — the SDS), the R's (the 1.0-8's — the 1.5's — the single), the DDBD's (the Caltrans' — the adopted; the displacement's), and the 1,000-year (the MCE's — the 7%'s; the 75's). The bridge's — the AASHTO designed.
Best price · Quotes back fast · PE stamps backed by Apex Grid Engineering
The AASHTO SGS
The SDC (the A's — the 4's; the 0.15's — the SDS), the 1,000-year (the MCE's — the 7%'s; the 75's), the R (the 1.0-8's — the 1.5's — the single's; the 5's — the multi's), the 2% (the drift's — the 0.04's; the P-delta's), and the 9th (the edition's — the 2020's; the SGS's).
The design's methods
The ELF (the single's — the 1.5's; the R's), the RSA (the multi's — the 5's; the CQC's), the DDBD (the Caltrans' — the adopted; the SDC's), the NLTHA (the 7's — the verified; the 1,000's), and the 1.0 (the R's — the critical's; the 0.67's — the joints').
Details
The 2-foot (the seat's — the width's; the 24-inch's — the minimum), the 1.5 (the shear's — the keys'; the 2's), the restrainers (the 1.0's — the cables'; the 2-foot's), the isolation (the 17's — the LRB's; the 2-3s's), and the 75-year (the design's — the 100's; the service's). The bridge's — the seat's width; the 2-foot's minimum.
The bottom line
Design bridges per AASHTO SGS 9th (SDC A-D by SDS, R 1.5 single/5 multi, 1,000-yr MCE, 2% drift) — provide 24-in minimum seat width, 1.5x shear keys, cable restrainers; Caltrans uses DDBD; consider isolation (2-3s) for 3-4x reduction.
Torch Engineering PLLC · (480) 490-0064 · info@torchengineering.com — PE stamping backed by Apex Grid Engineering.