Ductile Frames Are Tough for Earthquakes

by Sol E. Cooper, (F.ASCE), Vice-Pres. and Prin. Struct. Engr.; F. E. Jordan Associates, Oakland, CA,

Serial Information: Civil Engineering—ASCE, 1991, Vol. 61, Issue 8, Pg. 61-63

Document Type: Feature article


Implications of a new structural system in wharf design go far beyond San Francisco Bay, where two such wharves remained intact after the 1989 Loma Prieta quake. The design, introduced in Oakland in 1980, has been used in several West Coast ports and is now being adapted to repair some conventional wharves that were damaged in the quake. The basic concept of the new design is that wharves framed in ductile moment-resisting systems survive better in major earthquakes than do traditional braced frames. The continuous, moment-resisting frame is designed to resist horizontal forces with horizontal and vertical members joined by rigid joints. There is no need for diagonals (batter piles). Ductility is achieved by adding ductile reinforcing steel and heavy, closely spaced spirals to prestressed concrete piles. The design also requires landside piles that are restrained laterally, and a rock or earth prism, seismically stable itself and strong enough to effectively anchor the structural frame.

Subject Headings: Concrete piles | Seismic design | Ductility | Frames | Earthquakes | Moment (mechanics) | Reinforced concrete | Steel piles

Services: Buy this book/Buy this article


Return to search