1 Arlington Gateway Hotel Arlington Gateway Hotel Arlington, - - PDF document

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Arlington Gateway Hotel

801 North Glebe Road Arlington, Virginia

Michael Gray

Penn State University AE Senior Thesis Presentation 2005 Arlington, Virginia Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Background Current Structural System Alternate Structural Systems Structural Redesign Cost and Scheduling Final Recommendation

Outline of Presentation

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Site – Arlington Gateway

22 Story Residential tower 13 Story Office Building 15 Story Arlington Gateway Hotel Arlington, Virginia Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

General Information

• 250,000 Square Feet
• 335 Units
• Estimated cost $40 million
• Westin Hotel & Resort
• Located within 5 min. of Reagan National Airport

Amenities

• Starbucks Cafe
• Restaurant and Lounge
• Ballroom and Meeting Facilities
• Indoor Swimming Pool
• Fitness Center and Spa

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Structural System

• 4000 psi Concrete In Slabs
• Mix of 4000 to 6000 psi Concrete In Columns
• Reinforced Cast-In-Place Concrete
• 8” Two-Way Flat Slab Construction (Typical)

Design Codes

• BOCA 96
• ASCE 7-95

Lateral System

• Moment Frames

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Alternate Systems for Mid-Rise Residential Structures

• Hybrid Systems – Steel and Precast
• Prestressed Precast Concrete
• Metal Deck and Composite Steel Beams

Staggered Truss System The Girder-Slab System

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Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Alternate System Selection

• Any site constraints?
• How will it work with current floor plan?
• Will it maintain the current 8’-9” story height?

15 17 16 5 4 3 Adaptable to current layout 3 4 5 Speed of Construction 2 5 5 Light Weight 5 4 3 Fire Resistance Flat-Slab Girder-Slab Staggered Truss Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Structural Redesign – The Girder-Slab System

• Open Web Dissymmetric Beam (D-Beam)
• Composite Construction
• Uses precast hollow-core slabs

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Design Loads – Flooring System

• Corridors – 100 psf

ASCE 7-02 Minimum Design Live Loads

• Private Rooms - 40 psf

Dead Load

• 8” Hollow Core Plank – 56 psf
• Concrete Leveling Topping and Grout – 4 psf

Additional Live Load

• Partitions – 15 psf

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Design of Floor Members

• Spreadsheet Created With Member Properties

Checked Precomposite Deflections and Stresses Checked Composite Loads

• 4 Standard Sizes to select from with 8” slab

DB 8x35; DB 8x37; DB 8x40; DB 8x42 Checked Compressive Stress of Concrete Checked Stresses in Bottom Flange Checked Shear Capacity of Web Arlington, Virginia Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Conclusions Dead load deflection becomes an issue

• Limited clear span

Max span of 16’ when used with 28’ plank Use of tree columns

• Solutions

D-Beams can be made with camber Arlington, Virginia Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

How much will it cost?

• D-Beams cost around 65 cents to fabricate
• Standard wide flanges cost 35 cents to roll
• Rising material and labor costs
• 8” plank costs roughly $7.50/s.f.

$22 Girder-Slab $30 CIP Flat-Slab $25 Staggered Truss Cost Per Square Foot Structural System Assemblies Cost

• Could save $2 million over CIP

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Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Scheduling

• 15,000 s.f. per week
• Superstructure constructed in just 15 weeks
• Can place 40-60 plank per day
• Steel and plank erected at same time
• 25% reduction in construction schedule

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Scheduling - Examples

• Housing project at Princeton University

superstructure finished in 4 weeks

• 8 story Drexel Dormitory superstructure

finished in 31 days 2 5-story buildings with one crane Totaling 96,000 s.f. Arlington, Virginia Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

Recommendation – The use of Girder-Slab Technology

• Reduced cost
• Innovative use of steel
• Reduces construction schedule over CIP
• Reduces overall weight of structure by 40%

Arlington, Virginia

Michael Gray Structural Option

Arlington Gateway Hotel

Introduction Background Current Structure Alternate Systems Structural Redesign Cost and Scheduling Recommendation

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