Winning the “bridging” design-build contract for the University of California, San Francisco’s stem-cell research laboratory, a serpentine cliff-hanger in a high seismic zone, put the design-build team on a slippery slope. The steep hillside site for the 660 x 70-ft lab, set on an external, expressed and base-isolated space truss, was unstable, inaccessible and squeezed on one side by active hospitals on the university’s Parnassus campus. When bridging documents were released in January 2008, conceptual design by Rafael Vi�oly Architects was for a lab that would have cost at least $20 million more than the approximately $76-million target cost. And
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.