The Girder-Slab® System Design Guide v3.2 LRFD

v3.2

07

G I R D E R - S L A B ® S Y S T E M / D E S I G N G U I D E v 3 . 2

v3.2

GIRDER-SLAB®DESIGN GUIDE v3.2

Mid to high-rise residential structures have traditionally used a cast-in-place reinforced concrete structural system which offers such benefits as low floor to floor height and fireproof construction. With similar benefits, low to mid-rise buildings often utilize bearing wall systems supporting precast slabs. These structural systems are time consuming, weather sensitive and labor intensive.

Girder-Slab® Technologies, LLC set out to develop a more efficient structural steel based framing system for mid and high-rise residential construction.

Utilizing proven materials that have long been used by the construction industry, the Girder-Slab® System is designed by the owner’s architect and structural engineer and is available competitively from the builder’s customary steel fabricators.

The components of the system, structural steel (including the D-Beam® Girder) and precast hollow-core slabs, can be manufactured and supplied by many subcontractors guaranteeing the owner competitive procurement of the building’s superstructure.

An innovative design with a conventional approach.

2GIRDER-SLAB®DESIGN GUIDE V3.2


The D-Beam® Girder


With practically an unlimited source of supply, the D-Beam Girder is manufactured by your local steel fabricators as part of a complete structural steel package.

The D-Beam fabrication process begins with a standard wide flange section that when uniquely cut through the web produces two identical T sections.

The fabricator then welds a flat bar to create the top flange resulting in two D-Beams from one parent beam without waste.


Neutral Axis

SlabGroutSteel


The Girder-Slab® System and the open web D-Beam® technology are the result of more than fifteen years of research and development. Early testing produced an ASD approach for a rational design of the Girder-Slab® System.

In order to develop a rational analysis that would maximize the use of this technology, extensive laboratory testing and analysis was undertaken. This included both small-scale specimens and full-scale assemblies in order to simulate actual bays. Each assembly was load tested well above code required residential live loads. The D-Beam® Girder performed without failure even at these higher loads.

Recent, more sophisticated testing enabled us to develop an LRFD approach to the Girder-Slab® System. Design Guide v3.1 LRFD improved upon the previously established structural and economical benefits of the Girder-Slab® System. With simplicity in mind, new D-Beams® have been introduced while others, less commonly used, have been eliminated.

The Girder-Slab® System integrates easily with lateral resisting steel braced frames, and concrete or masonry shear walls.



DB8 indicates 8” D-Beam® Girder Section

indicates 8” Precast Hollow-Core Slab

DB8

DB8

DB8

DB8

DB8

DB8

DB

8

W18

W12

W18

DB8

DB8

DB8

DB8

DB8

DB8

W18

W21

W18

DB8

W10

W10

DB8

W10

W10

W10

W10

W10

W10

W10

W10

W10

W10

W10

W10

W10

W10

W12

W12

W12

W18

W10

W10

W10

W10

W10

W10

W10

W10

W12

W12

W18

W12

HSS

HSS

HSS

STAIR

STAIR

ELEV.

ELEV.

ELEV.

W21 W

21

W18

W18

BF

BF

BF

BF

BF

BF

BF

Framing Plan Example

DB 8 x 37 36.7 10.8 8 W 12 x 53 3/8 9/16 10 2 5 3 1

DB 8 x 39 39.2 11.5 8 W 12 x 58 3/8 5/8 10 1 3/4 5 1/4 3 1

DB 8 x 42 41.8 12.3 8 W 12 x 53 3/8 9/16 10 1 5 1/2 3 1 1/2

DB 8 x 45 44.3 13.0 8 W 12 x 58 3/8 5/8 10 3/4 5 3/4 3 1 1/2

DB 8 x 57 56.5 16.6 8 W 12 x 79 1/2 3/4 12 1/8 1 5/8 5 3/8 5 1

DB 8 x 61 60.8 17.9 8 W 12 x 79 1/2 3/4 12 1/8 1 1/8 5 5/8 5 1 1/4

Designation

Web Included Weight

(lb/ft)

AverageArea

(in2)

Depth

(d)

(in)

Parent Beam Size

Web Thickness

(tw)

(in)

Flange Thickness

(tf)

(in)

Flange Width

(bf)

(in)

a

(in)

b

(in)

w

(in)

t

(in)

DB 9 x 41 40.7 12.0 9 5/8 W 14 x 61 3/8 5/8 10 3 3/8 5 1/4 3 1

DB 9 x 45 44.2 13.0 9 3/4 W 14 x 68 7/16 3/4 10 3 1/2 5 1/4 3 1

DB 9 x 46 45.8 13.5 9 5/8 W 14 x 61 3/8 5/8 10 2 3/8 5 3/4 3 1 1/2

DB 9 x 48 47.2 13.9 9 13/16 W 14 x 74 7/16 13/16 10 1/8 3 1/2 5 5/16 3 1

DB 9 x 49 49.3 14.5 9 3/4 W 14 x 68 7/16 3/4 10 2 1/2 5 3/4 3 1 1/2

DB 9 x 52 52.3 15.4 9 13/16 W 14 x 74 7/16 13/16 10 1/8 2 1/2 5 13/16 3 1 1/2

DB 9 x 57 56.5 16.6 9 3/4 W 12 x 79 1/2 3/4 12 1/8 5 1/8 3 5/8 5 1

DB 9 x 65 65.0 19.1 9 3/4 W 12 x 79 1/2 3/4 12 1/8 4 1/8 4 1/8 5 1 1/2

D-Beam®

Dimensions


ASD9TH

Edition

ASD14TH

Edition

LRFD14TH

Edition

Fy = 50 ksi

Designation Ix

(in4)

NAbot DB

(in)

Sbot

(in3)

Stop

(in3)

Qtop bar

(in3)

PNAbot DB

(in)

Z

(in3)

Mallow

(kip-ft)

Mn/Ωb

(kip-ft)

φbMn

(kip-ft)

DB 8 x 37 105 2.79 37.7 20.2 14.1 0.51 26.1 50.4 65.0 97.7

DB 8 x 39 108 2.69 40.3 20.4 14.4 0.55 26.5 51.0 66.2 99.5

DB 8 x 42 126 3.32 38.0 27.0 17.7 1.53 35.9 67.6 89.6 134.6

DB 8 x 45 131 3.21 40.8 27.4 18.2 0.85 36.7 68.5 91.5 137.5

DB 8 x 57 169 2.93 57.7 33.3 22.9 0.68 42.4 83.2 105.9 159.2

DB 8 x 61 188 3.22 58.2 39.2 26.0 0.73 50.8 98.1 126.6 190.3

DB 9 x 41 161 3.13 51.4 24.8 18.0 0.55 31.4 62.0 78.4 117.8

DB 9 x 45 173 2.92 59.1 25.3 19.0 0.62 32.6 63.3 81.3 122.2

DB 9 x 46 198 3.79 52.2 33.9 22.9 0.85 44.0 84.8 109.7 164.9

DB 9 x 48 179 2.83 63.1 25.6 19.5 0.65 33.0 63.9 82.4 123.8

DB 9 x 49 215 3.55 60.6 34.7 24.5 0.71 45.4 86.8 113.2 170.2

DB 9 x 52 224 3.44 65.0 35.2 25.3 0.74 45.9 87.9 114.5 172.0

DB 9 x 57 258 3.40 76.0 40.7 29.3 0.64 47.8 101.7 119.3 179.4

DB 9 x 65 314 4.10 76.6 55.7 36.7 0.84 68.1 139.2 170.0 255.5

D-Beam®

Properties


Sample Calculations8” D-Beam DB 8 x 61 with 8” Hollow-CoreLRFD


Note: Graphical representation only.The online D-Beam Calculator Reference Tool v3.1 is intended for use

only with assemblies identical to S1 and S3 in Girder-Slab Design Guide v3.2.

9” D-Beam DB 9 x 65 with 10” Hollow-CoreLRFD


Note: Graphical representation only.The online D-Beam Calculator Reference Tool v3.1 is intended for use

only with assemblies identical to S1 and S3 in Girder-Slab Design Guide v3.2.






DB8D-BEAM®

PRECAST CONCRETESLAB

GROUT

METAL STUD PARTITIONGYPSUM BOARD &OPTIONAL

8”

(1) LAYER GYPSUM BOARD (REFER TO U.L. K912)

METAL STUD PARTITIONGYPSUM BOARD &OPTIONAL

OPTIONALCROWNMOLDING

8” GROUT

SPRAYFIREPROOFING(REFER TO U.L. K912)


DB8D-BEAM®

DB8D-BEAM®


GROUT8”

PIPING &MECHANICALCHASE

11 1/4”

MIN.


DB8D-BEAM®

GROUT8”

STRUCTURAL,PIPING, &MECHANICALCHASE

11 1/4”MIN.



The Girder-Slab® System Design Guide v3.2 and technology is available for use by industry professionals. Application and use of this information requires design by a registered professional structural engineer.

Structural Engineers are asked to add the following Girder-Slab® System Specification Guide to the General Notes section of their construction documents. The Specification Guide and the Typical System Structural and Architectural Details are available in both CAD and PDF formats on the Design Team Resources page of the Girder-Slab website. www.girder-slab.com

The Girder-Slab® System and D-Beam® Girder are available from your customary steel fabricators. Fabrication, construction, and assembly shall be in conformance with the Girder-Slab® System Design Guide v3.2 specifications and details.

SPECIFYING THE GIRDER-SLAB® SYSTEM TECHNOLOGY v3.2

Fire Resistance InformationFire Resistance Rating — ANSI/UL 263Design No. K912April 19, 2001Restrained Assembly Ratings — 3 Hr.Unrestrained Assembly Ratings — 2 Hr.Unrestrained Beam Ratings — 2 Hr.

ALSO AVAILABLE IN CANADA

Summarized from UL #K912. Please refer to the current online

Certifications Directory for modifications or updates.



The application and use of the Girder-Slab® System technology requires design by your registered professional engineer or architect. This Design Guide provides engineering information and is available for use by industry professionals.

Girder-Slab Technologies, LLC is a marketing company. We inform design and construction professionals, supply design tools and details, and assist the engineer of record on an as needed basis. Girder-Slab Technologies can help you determine whether or not the Girder-Slab® System will add value to your project.

GIRDER-SLAB®DESIGN GUIDE V3.2


11 UL K912


10 Eliminate Beam Penetrations09 Gypsum Wall Board Ceiling

12 Various Architectural Designs




GIRDER-SLAB®DESIGN GUIDE V3.2 28

29 GIRDER-SLAB®DESIGN GUIDE v3.2

GIRDER-SLAB®DESIGN GUIDE V3.2 30

Documents

The Girder-Slab® System Design Guide v3.2 LRFD