Jay AllenPresident

Jim PartridgeSecretary & CFO

The SlottedWeb™ Steel Moment Connection

Seismic Structural Design Associates

Jay Allen, S.E.President

(602) 251-0329

Jim Partridge, C.E.Secretary & CFO

(213) 749-3411

http://slottedweb.com

1

What Is SlottedWeb™ Technology?

The SlottedWeb™ structural steel seismic connection developed by Seismic Structural Design Associates Inc.(SSDA) has been approved for general use as a pre-qualified connection in Special Moment Frames (SMF) bythe International Code council (ICC). The design, fabrication, and field inspection requirements for thisconnection is given in ER-5861, which may be down loaded from the ICC website (www.icc-es.org). Thisconnection also satisfies the April 15, 1997 AISC Seismic Provisions for Structural Steel Buildings and itsSupplements No.1 dated February 15, 1999 and No.2 dated November 10, 2000. A description of thisproprietary connection is also shown in FEMA-350 "Recommended Seismic Design Criteria for New SteelMoment-Frame Buildings" and in FEMA-351 "Recommended Seismic Evaluation and Upgrade Criteria forExisting Steel Moment-Frame Buildings".

The ICC approval includes seismic moment frame designs using either deep or standard columns withoutlateral column bracing. Moreover, no bracing of the beam at the connection is required. These exclusiveassets derive from the SlottedWeb™ technology, which eliminates both the lateral torsional buckling modeand virtually all of shear in the beam flanges.

The SlottedWeb™ connection technology and designs were developed by SSDA through an extensiveprivately funded research and development effort. These cost effective connections have gained widespreadacceptance by structural engineers as demonstrated by their use in over 220 buildings including commercialoffice buildings, hospitals, schools, hotels, and residential structures.

Approved for Use by: ICC, AISC, OSHPD to W36 x 393 #/Ft

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Detail Notes Example

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How Much Does the SlottedWeb™ Save?

SlottedWeb™ (SW) vs. Dogbone (RBS) Connection

1. RBS moment frame beams are heavier than SW beams. This is because seismic lateral story driftcontrols the design of Special Moment Frames so that RBS beams, due to their reduction in stiffness, aretypically one to two sizes heavier than SW moment frame beams. For example, in Reference (1) parametricstudies were conducted on six-story two- and three-bay moment frames subjected to seismic base shears. Lateralstory drift coefficients of the frames with and without RBS beams were compared. The frames with RBS beamswere designed with a 40% reduction in their flange areas. When compared to frames without the RBS cuts,these flange reductions showed a 10.6% increase in story drift for the two-bay frame and a 10.3% increase inthe story drift for the three-bay frame.

2. Fabrication of SW beams is more economical than for RBS beams. Only two web cuts are requiredfor the SW beams whereas four flange cuts are required for the RBS beams. Moreover, web cuts involve thethinner web material than the thicker flange material. Additionally, no special surface preparation is requiredfor the SW weld access holes, which may be flame-cut.

3. Field inspection of the connection weldments is significantly reduced. For the SW moment frameconnections, the nondestructive testing rate for an individual welder or welding operator may be reduced from100% to 25%, provided the reject rate is demonstrated to be 5% or less for the welds tested for the welder orweld operator. A sampling of at least 40 completed welds for a job shall be made for such reduced evaluation.(See Reference 2, Section 2)

1. Chambers , J.J., et al., "Effect of Reduced Beam Section Frame Elements on the Stiffnes s of Moment Frames", Journal of Structural Engineering,ASCE, March 2003, pp. 383-393.

2. Engineering Report 5861, ICBO Evaluation Service, Inc., Whittier, CA, May 1, 2002.

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Real-World Savings Estimates

Below are steel bids from four independent steel fabricators for a project in Irvine, CA. Eachfabricator priced the SSDA SlottedWebTM moment connection as well as the Reduced BeamSection (RBS - a.k.a. Dogbone) and the ICF/Kaiser Moment Connection Detail.

Building Office Tower

Size 280,000 sq. ft.

Location Irvine, CA

# Moment Frame

Connections 750

Contractor #1 Contractor #2 Contractor #3 Contractor #4 AVERAGE

SSDA SlottedWeb™ Detail

Cost per Connection $1,004.00 $1,473.00 $1,484.00 $3,397.00 $1,839.50

Design Fee $40,000.00 $40,000.00 $40,000.00 $40,000.00 $40,000.00

Connections Cost + Fee $793,000.00 $1,144,750.00 $1,153,000.00 $2,587,750.00 $1,419,625.00

Dogbone Detail

Cost per Connection $1,549.00 $2,144.00 $1,754.00 $4,000.00 $2,361.75

Total Cost of Connections $1,161,750.00 $1,608,000.00 $1,315,500.00 $3,000,000.00 $1,771,312.50

Cost INCREASE over

SlottedWeb™ $368,750.00 $463,250.00 $162,500.00 $412,250.00 $351,687.50

ICF/Kaiser Detail

Cost per Connection $1,204.00 $2,157.00 $1,781.00 $4,244.00 $2,346.50

Total Cost of Connections $903,000.00 $1,617,750.00 $1,335,750.00 $3,183,000.00 $1,759,875.00

Cost INCREASE over

SlottedWeb™ $110,000.00 $473,000.00 $182,750.00 $595,250.00 $340,250.00

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Completed SSDA Projects

Yerba Buena Tower

San Francisco

•37 Stories

•1.3 million Sq. Ft.

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Completed SSDA Projects

GAP Embarcadero

San Francisco

•15 Stories

•400,000 Sq. Ft.

7

Completed SSDA Projects

Hyatt San Diego

San Diego

•32 Stories

•450,000 Sq. Ft.

8

Recent Testing for El Camino Hospital

The following test results include• A very significant factor of safety against failure• Rotations to 5 and 6 radians• Proof of very high shear carrying capacity of 970K for a W36 x 393

beam

The attached OSHPD approval includes• Deep Column use (>W14 columns)• Beam size to W36 x 393• Beam span minimum at 20’-0”