jonathan goodroad structural option 2005 thesis penn state ae delaware state university...
TRANSCRIPT
Jonathan GoodroadJonathan GoodroadStructural OptionStructural Option2005 Thesis2005 ThesisPenn State AEPenn State AE
Delaware State Delaware State University University
Administration and Administration and Student Services Student Services
BuildingBuilding
DSU Administration BuildingDSU Administration Building
4-Story Office Building4-Story Office Building 88,600 SF88,600 SF Southeast corner of DSU campusSoutheast corner of DSU campus
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction Issues Breadth Study – Construction Issues Breadth Study – Mechanical Loading AnalysisBreadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction IssuesBreadth Study – Construction Issues Breadth Study – Mechanical Loading Analysis Breadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
Building BackgroundBuilding Background
Location: Dover, DelawareLocation: Dover, Delaware Cost: $17.5 millionCost: $17.5 million Project Team:Project Team:
– Owner: Delaware State University– Architect: H2L2 Architects– Civil Engineer: George, Miles and Buhr, LLP– Landscape Architect: Synterra– Structural Engineer: CVM Engineers– MEP Engineer: Mark Ulrick Engineers– Construction Manager: EDiS
Building BackgroundBuilding Background ArchitectureArchitecture
Vertical Circulation
Lounge Area
Offices
Entrance Area
Vertical Circulation
Building BackgroundBuilding Background
East portion w/ basement + 4 stories East portion w/ basement + 4 stories + mechanical penthouse+ mechanical penthouse
West portion w/ single-story offices West portion w/ single-story offices and 2-story atriumand 2-story atrium
Building BackgroundBuilding Background
Existing StructureExisting Structure– GravityGravity
Composite steel beam with reinforced concrete slab Composite steel beam with reinforced concrete slab on composite deckon composite deck
3” concrete slab on 2 ½” 20 gage deck3” concrete slab on 2 ½” 20 gage deck Alternating 28’ x21’4” and Alternating 28’ x21’4” and
28’ x22’8” typical bays28’ x22’8” typical bays Typical W16x26 beamsTypical W16x26 beams Typical W24x55 girdersTypical W24x55 girders
Building BackgroundBuilding Background Existing StructureExisting Structure
– LateralLateral Semi-rigid moment connectionsSemi-rigid moment connections Masonry shear walls around elevatorsMasonry shear walls around elevators
Existing StructureExisting Structure – FoundationFoundation
East portion uses 24” mat foundationEast portion uses 24” mat foundation West portion slab on grade with square footings West portion slab on grade with square footings Piers around perimeter of entire footprintPiers around perimeter of entire footprint Grade beam around perimeter of slab on gradeGrade beam around perimeter of slab on grade Wide grade beam down center of matWide grade beam down center of mat
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction IssuesBreadth Study – Construction Issues Breadth Study – Mechanical Loading Analysis Breadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
Depth StudyDepth Study
Redesign ProposalRedesign Proposal– Change from steel frame system to cast-Change from steel frame system to cast-
in-place reinforced two-way flat plate in-place reinforced two-way flat plate systemsystem
– Exploration of the concrete design Exploration of the concrete design processprocess
– Compare feasibility differences between Compare feasibility differences between the two systemsthe two systems
Depth StudyDepth Study
Gravity SystemGravity SystemDesign Goals:Design Goals:
Uniform bay sizesUniform bay sizes Consistent column Consistent column
dimensions dimensions – Floor to floorFloor to floor– Across floor planAcross floor plan
Limited effect on Limited effect on architecturearchitecture
– Space dimensionsSpace dimensions– Travel penetrationsTravel penetrations
Design Guides:Design Guides: IBC 2003IBC 2003 ACI 318-02ACI 318-02
Design Analyses:Design Analyses: Equivalent Frame Equivalent Frame
AnalysisAnalysis ADOSSADOSS ETABSETABS
Depth StudyDepth Study
Gravity SystemGravity SystemLoads:Loads:
Floor DeadFloor Dead 20 psf20 psf
Roof DeadRoof Dead 20psf20psf
Exterior WallExterior Wall1.4 klf1.4 klf
Conc. WeightConc. Weight145 pcf145 pcf
Floor LiveFloor Live 100 psf100 psf
Snow LoadSnow Load 20 psf20 psf
Materials:Materials:
4000 psi concrete4000 psi concrete
60000 psi reinforcing60000 psi reinforcing
Depth StudyDepth Study
Gravity SystemGravity SystemDesign:Design:
SlabsSlabs– ADOSS used for designADOSS used for design– 12” flat plate slab12” flat plate slab– #5’s and #7’s#5’s and #7’s
Depth StudyDepth Study
Gravity SystemGravity SystemDesign:Design:ColumnsColumns– ETABS used for load ETABS used for load
determinationdetermination– 22”x 22” columns22”x 22” columns– Most longitudinal reinforcing Most longitudinal reinforcing
controlled by minimum controlled by minimum steel requirementssteel requirements Interior basement level excludedInterior basement level excluded
– Used 4 #10’s in most and 4 #18’s in basement Used 4 #10’s in most and 4 #18’s in basement interior columnsinterior columns
Depth StudyDepth Study
Gravity SystemGravity SystemDesign:Design:
ColumnsColumns
Shear stud strips provide Shear stud strips provide
necessary reinforcement necessary reinforcement
around column areas around column areas
with high shear stress with high shear stress
Max shear stress = 253 psiMax shear stress = 253 psi
Depth StudyDepth Study
Lateral SystemLateral SystemDesign GoalsDesign Goals– Reinforced concrete Reinforced concrete
shear walls used in shear walls used in vertical opening vertical opening locationslocations 2 elevators and 1 2 elevators and 1
mechanical shaftmechanical shaft
– Integrate columns as Integrate columns as
boundary elementsboundary elements
where possiblewhere possible
Design Guides:Design Guides: IBC 2003IBC 2003 ACI 318-02ACI 318-02 ASCE 7-02ASCE 7-02
Depth StudyDepth Study
Lateral SystemLateral System– Wind Load: Wind Load:
Determined from IBC 2003Determined from IBC 2003 Exposure Category C Exposure Category C Basic Wind Speed = Basic Wind Speed = 90 mph90 mph Importance Factor = Importance Factor = 1.15 (Category III)1.15 (Category III) Base Shear =Base Shear = 303 kips303 kips
Depth StudyDepth Study
Lateral SystemLateral System– Seismic Load:Seismic Load:
Determined with IBC 2003 (Chapter 16), ACI Determined with IBC 2003 (Chapter 16), ACI 318-02 (Chapter 21), and ASCE 7-02 318-02 (Chapter 21), and ASCE 7-02
Base Shear = 747 kips
Depth StudyDepth Study
Lateral SystemLateral SystemDesign:Design:
Shear wallsShear walls– Seismic loading governsSeismic loading governs– Stiffness analysis used for Stiffness analysis used for
wall load determinationwall load determination– ETABS used for strength andETABS used for strength and
deflection analysisdeflection analysis
Depth StudyDepth Study
Lateral SystemLateral SystemDesign:Design:
Flexural steel determined with minimum Flexural steel determined with minimum requirementsrequirements
Max steel ratio notedMax steel ratio noted Longitudinal spacing accounted forLongitudinal spacing accounted for Transverse steel spaced at 6”Transverse steel spaced at 6” Shear reinforcement spaced at 6”Shear reinforcement spaced at 6”
Depth StudyDepth Study
Lateral SystemLateral SystemDesign:Design:
Required SteelRequired Steel
(worst case for (worst case for
E-W direction)E-W direction)
Depth StudyDepth Study
Building ImpactBuilding Impact– Building weight greatly increasedBuilding weight greatly increased
Expensive existing foundation may not have Expensive existing foundation may not have capacity to expand on questionable soilcapacity to expand on questionable soil
– Thickness of shear walls may intrude Thickness of shear walls may intrude upon corridor spacesupon corridor spaces
– Floor to floor height reduced by 2’ per Floor to floor height reduced by 2’ per floor, overall building height reducedfloor, overall building height reduced
– Fire rating of 4 hours for concrete, no Fire rating of 4 hours for concrete, no spray on fireproofing requiredspray on fireproofing required
Depth StudyDepth Study
System ComparisonSystem Comparison– Steel system cost approximately $1.5 millionSteel system cost approximately $1.5 million– Concrete system cost approximately $1.9 Concrete system cost approximately $1.9
millionmillion– Concrete requires little lead timeConcrete requires little lead time– Steel construction more preciseSteel construction more precise– Steel system can be fabricated in any Steel system can be fabricated in any
temperaturetemperature Concrete requires warmer temperatures Concrete requires warmer temperatures
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction IssuesBreadth Study – Construction Issues Breadth Study – Mechanical Loading Analysis Breadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
Breadth StudyBreadth Study
Construction IssuesConstruction Issues– Concrete constructionConcrete construction
Uniform bays allows for faster floor cycle with consistent Uniform bays allows for faster floor cycle with consistent formworkformwork
– Use of flying forms allows for thisUse of flying forms allows for this Consistent column dimensions add to ease of erectionConsistent column dimensions add to ease of erection
– Rebar changes, dimensions do notRebar changes, dimensions do not Use of #18 bars in basement columnsUse of #18 bars in basement columns
– Requires crane for placementRequires crane for placement Smaller bars may be better choiceSmaller bars may be better choice
Shear stud stripsShear stud strips– Reduces congestion at column locationsReduces congestion at column locations– Provides shear reinforcement without labor of bending barsProvides shear reinforcement without labor of bending bars
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction IssuesBreadth Study – Construction Issues Breadth Study – Mechanical Loading AnalysisBreadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
Breadth StudyBreadth Study
Mechanical Loading AnalysisMechanical Loading Analysis– South facing atrium spaceSouth facing atrium space
Analyze effect of Analyze effect of glazing on cooling glazing on cooling loadload
Using Hourly Using Hourly Analysis Program, Analysis Program, take sample space take sample space and determine and determine effectseffects
Breadth StudyBreadth Study
Mechanical Loading AnalysisMechanical Loading Analysis– U-value and shading coefficient effect U-value and shading coefficient effect
heat transmission through glazingheat transmission through glazing– U-value is measure of ability to conductU-value is measure of ability to conduct
Lower value = lower heat transmittanceLower value = lower heat transmittance
– Shading coefficient is ratio of heat gain Shading coefficient is ratio of heat gain through selected glazing to heat gain through selected glazing to heat gain through single pane of clear glazingthrough single pane of clear glazing Expressed as <1 Expressed as <1 Lower value = lower heat transmittanceLower value = lower heat transmittance
Breadth StudyBreadth Study
Mechanical Loading AnalysisMechanical Loading Analysis– Existing glazing: Existing glazing:
U = 0.29U = 0.29 SC = 0.44SC = 0.44
– New glazing:New glazing: U = 0.31U = 0.31 SC = 0.20SC = 0.20
Breadth StudyBreadth Study
Existing System Cost: $73,500Existing System Cost: $73,500 Proposed System Cost: $85,000Proposed System Cost: $85,000 Difference: $11,500Difference: $11,500 Payback: 4.6 yearsPayback: 4.6 years
OutlineOutline Building BackgroundBuilding Background
– GeneralGeneral– ArchitectureArchitecture– Existing StructureExisting Structure
Depth Study – Redesign with Two-way Flat Plate SystemDepth Study – Redesign with Two-way Flat Plate System– Redesign ProposalRedesign Proposal– Gravity SystemGravity System– Lateral SystemLateral System– Building ImpactBuilding Impact– System ComparisonsSystem Comparisons
Breadth Study – Construction IssuesBreadth Study – Construction Issues Breadth Study – Mechanical Loading Analysis Breadth Study – Mechanical Loading Analysis ConclusionsConclusions AcknowledgementsAcknowledgements QuestionsQuestions
ConclusionsConclusions
Concrete design would use 12” slab, Concrete design would use 12” slab, 22” square columns, and 16” 22” square columns, and 16” reinforced concrete shear wallsreinforced concrete shear walls
Steel system more cost effective Steel system more cost effective optionoption
Coordination of trades would require Coordination of trades would require more work for a concrete systemmore work for a concrete system
Better glazing can improve energy Better glazing can improve energy costscosts
AcknowledgementsAcknowledgements
Thanks to…Thanks to…– PSU AE FacultyPSU AE Faculty– Delaware State UniversityDelaware State University– CVM EngineersCVM Engineers– Family and FriendsFamily and Friends– Holly and ToddHolly and Todd
?Questions??Questions?