SSDA Files Patent Infringement Suit Over Unauthorized Use of Structural Steel Seismic Connections in Building of Constellation Place

Sep 16, 2005, 01:00 ET from Venable LLP

    LOS ANGELES, Sept. 16 /PRNewswire/ -- Construction engineering firm
 Seismic Structural Design Associates, Inc. (SSDA) has filed a patent
 infringement lawsuit alleging that a structural engineering firm has used its
 patented award-nominated SlottedWeb(TM) structural steel seismic connection in
 building construction without authorization. The SlottedWeb connection is a
 cost-effective, structurally important design that has become the standard for
 earthquake resistant construction. Washington, DC-based law firm Venable LLP
 will represent SSDA in the patent action.
     The suit, filed yesterday in Los Angeles federal district court, charges
 that WHL Consulting Engineers, Inc. and its Principal, Lauren D. Carpenter,
 Ph.D. have engaged in various infringements of SSDA's patented designs,
 including at Constellation Place, a high-rise property designed by architect
 Johnson Fain Partners, developed by JMB Realty Investment Partners, and built
 by Hathaway-Dinwiddie Construction with steel subcontractor Herrick
 Corporation. The suit seeks actual and enhanced money damages, and a
 preliminary and permanent injunction prohibiting WHL and Dr. Carpenter from
 using SSDA's patented designs.
     The SlottedWeb connection, which was nominated for a 2002 NOVA Award for
 innovation in the construction industry, works to improve the popular but
 fundamentally flawed pre-Northridge earthquake field-welded, field-bolted
 beam-to-column moment frame connection.  Longitudinal slots are cut to
 separate beam flanges from the beam web in the region of the connection, and
 the beam web is welded to the column flange.  These changes dramatically alter
 the force, stress, and strain distributions to make the connection cost
 effective for both new and retrofit construction.
     There are two other designs that also fix the pre-Northridge flaw, but
 both are significantly more expensive than the SlottedWeb. The SlottedWeb
 connection has been approved for general use as a pre-qualified connection in
 Special Moment Frames (SMF) by the International Code Council (ICC). It also
 satisfies the April 15, 1997 Seismic Provisions for Structural Steel Buildings
 of the American Institute for Steel Construction (, as
 well as its Supplements No. 1 dated February 15, 1999 and No. 2 dated November
 10, 2000. A description of the SlottedWeb connection is also shown in widely
 disseminated publications of the Federal Emergency Management Agency
 (, such as FEMA-350 "Recommended Seismic Design Criteria
 for New Steel Moment-Frame Buildings," and in FEMA-351 "Recommended Seismic
 Evaluation and Upgrade Criteria for Existing Steel Moment-Frame Buildings."
     SlottedWeb(TM) is a trademark of Seismic Structural Design Associates,
 Inc.  All rights reserved.
     To speak with James R. Burdett, the Venable partner who is representing
 SSDA, please contact Joshua Spivak at (510) 849-1663 or, or
 Sarah Gudsnuk at (202) 344-8523 or