SB BHS Repair and Replacement (OWPR) Power Point) September 23 2010 (2)

8/7/2019 SB BHS Repair and Replacement (OWPR) Power Point) September 23 2010 (2)

1/81

Blacksburg High School

Repairs and Gym ReplacementSeptember 23, 2010


2/81

Team

OWPRArchitects and Engineers

Contractors

Dr. Barker Independent StructuralConsultant verifyingOWPRs methodology

Town ofBlacksburg

Montgomery County

Public Schools

Testing Agencies

MBPConstruction Manager


3/81

Investigation and Testingthat has occurred at Blacksburg High School

Investigation/Testing Findings

1. OWPR Facility Assessment

Visual inspection of building components and systems

Floor elevation survey (documenting floor level and flatness)

Repairs necessary - (Category 1 Items)

2. Wall Settlement

Electrical resistivity testing Used ground probes in a grid arrangement throughout the

building and site to profile subsurface conditions

Test Borings

Drilled test borings in several locations inside and outside ofbuilding to identify soils and subsurface conditions

Data indicated no large voids under building. Data

found four possible voids outside of the building. Testborings are recommended at these locations todetermine if open voids are present.

No unusual soil conditions and no unusual subsurfacefindings, other than those at three locations whereunderpinning can be installed.

3. Auditorium Structural System Repair Forensic Engineer investigation of the gym collapse (FORCON)

Auditorium structural steel roof framing members and welds

Used ultrasound to examine full-penetration welds

Repairs necessary to Auditorium steel construction(similar to gym)

4. Deficient Concrete Beams

Non-destructive testing to determine size, quantity, and location of

reinforcing steel in concrete beams (28% of beams tested)

Used ground penetrating radar (GPR) and R meter

Used destructive testing to verify the results

Reinforcing steel strength testing

Repairs necessary

100% of beams need to be tested


4/81

Ccr

Ccr

Geology of the Site

ATS InternationalAdvanced Technical Services

www.ats-intl.com

mCopper Ridge Formation (lower Knox Group): Interbedded medium-gray. fine- to medium-grained. locaJJyCcr crossbedded sandy dolomite and medium-gray. finegrained, rrKlssive dolomite. s. upper siliceous oolite and- " " quartzose sandstone; discontinuous sandstone and sili-_ (, ceous oolite near the middle; and basal {eldspathic':i sandstone. Tellerina (F-946), an indicator or Tremp-ealeau age. is found within one horizon. The uppersandstone marker bed consists of about 10-20 feet(3.1-6.1 m) of interbedded siliceous oolite andmedium-grained quartzose sandstone. The bm;al sandstone marker bed consists of about 10-20 feet (3.1-6.1 m) o f predominantly light-gray, fine- to mediumgrained feic/$pathic sandstone interbedded with lesseramounts of sandy dolomite. Total thickness is about1200 feet (366 m). The soil is characterized by a thick(10-20 feet; 3.1-6.1 m) colluvial mantle with abundantsiliceous oolite, sandstone, and chert detritus overlyinga thick brown subsoil and saprolite.


5/81

Summary of Karst Formation

Rainwater becomes slightlyacidic with dissolved CO2.

Water percolates intolimestone bedrock alongfractures, joints, bedding

planes

Limestone or dolomite

slowly dissolves away,forming cave passages andnatural conduits for waterflow


www.ats-intl.com


6/81

Sinkhole Formation- Cover Subsidence


www.ats-intl.com


7/81

Sinkhole Formation- Cover Collapse


www.ats-intl.com

Overburdenm o r y day)


8/81

Types of Karst Features


www.ats-intl.com

r

l( ~

.-"-E'08-


9/81

Resistivity Imaging for Identifying Karst

~46cm(18

in)


www.ats-intl.com


10/81

Factors Effecting Resistivity

Moisture

Grain Size

Mineral Content


www.ats-intl.com


11/81

Voids

Sinkholes

Voids


www.ats-intl.com


12/81

Potential Ledges or Float

Cutters and Pinnacles

Cutters and Pinnacles


www.ats-intl.com


13/81

Collected Data for 12 Resistivity Sections


www.ats-intl.com

Ii(

..


14/81

9

Line 9

possible fracturezones

Results of Line 9


www.ats-intl.com


15/81

1

5

Southwest Northeast

Line 5

bedrockwall

likely fractureand/or solutional

zones

Line 1

gymnasiumTennis courts

likelyfracture

zone

possiblesolutional zones

possiblesolutional zone

Results of Lines 1 and 5


www.ats-intl.com


16/81

Lines of Evidence That the Problem is Not

From Ongoing Geologic Processes

The Copper Ridge Formation is not a

Strong Karst Former

There are no Sinkholes, Springs, or

Disappearing Streams on or Near the Site Water is the Engine to Ongoing Karst

Formation- Hardscape Prevents Infiltration There is no Evidence in the Geophysical

Data of Voids Beneath the Building


www.ats-intl.com


17/81

Questions about Testing and Investigations

//

ARCHITECTS AND ENGINEERS


18/81

1. Category 1 items from OWPR Facility Assessment

2. Wall settlement in three locations

3. Auditorium roof structural steel

4. Deficient concrete beams

Items to be Repaired


19/81

Repair of Category I Items from OWPR FacilityAssessment

Issue Solution Spalling concrete on columns and beams Epoxy mortar repair

Cracks Epoxy injection

Collateral damage from gym collapse Repair as required


20/81

Estimate for Cost of Category 1Repairs

Description Budget Estimate BidorProposal

1.Category1ItemsfromOWPRFacilityAssessment $ 141,000.00 General&Mech.Services(GMS)


21/81

Questions about the Repair of Category 1 Itemsfrom the OWPR Facility Assessment

//

M BOLYARDPECKBP McDONOUGH



22/81

Wall Settlement in Three Locations

Issue Solution

Wall settlement in Boiler Room, Auto Shop, and Wood Working Shop Install foundation underpinning (helical piers)


WallSettlementRepairsinthreelocations $ 66,000.00 RACConstructionCompany


23/81

Questions about Wall Settlement Repairs

//




24/81

Auditorium Roof Structural Steel

Issue Solution

Defective full-penetration welds at various locations

Various under-sized steel truss members

Reinforce welds with additional steel plates

Reinforce with additional steel members

Note: A 30 length of the west wall of the auditorium exceeds the

maximum allowable height for its construction and will require steelbracing to the roof framing. This work will be done when theauditorium trusses are repaired and will be concealed above theceiling.


AuditoriumRoofStructuralSystem $ 170,000.00 CSESteelErection&GMS

Cross Section of Failed Weld from Gym Truss Seat Auditorium Truss Seat


25/81

Questions about Auditorium Repairs

, /

/

M B ~ ~ H ARCHITECTS AND ENGINEERS


26/81

Deficient Concrete Beams

Issue Solution

Inadequate reinforcing steel within concrete beams Carbon fiber reinforcement or additional steeland concrete

Area of Destructive Testing to Verify Reinforcing Steel


27/81

Concrete is artificial stone

Steel reinforcing is placed in the tension zone

The two materials are combined, each material utilizing its bestproperties

Reinforced Concrete 101


28/81

Water flows down hill

You cannot push rope

Bodies in motion produce forces

Basic Civil Engineering Principles


29/81

Bending moments must balance; externally and internally

Bending Moment a force times a distance

G


30/81

Beam a horizontal structural member supporting vertical loads by bending

Glossary

Gl


31/81

Cantilevered Beam a beam that projects beyond a supportingcolumn or wall

Glossary

Gl


32/81

Column A vertical structural member supporting vertical loads bycompression

Glossary

C

C ti R i f d C t B


33/81

Continuous Reinforced Concrete Beam

I ,I. ITI

,I. ,I I J J JTI

" ,l I,

Where is the tension?

TIT T TTIT T TTIT// Where does the steel g07IT IT IT

What happens i f new supports are added between columns?

,I. ,I. ,lTI

I ,I. I,

T TTIT

IT

I, 1 1

T

IT

TIT

IT

MBP McDONOUGHBOLYARDPECK


I d d t R i f OWPR M th d l


34/81

Used original engineering drawings, specifications, schedules andbuilding codes

Verified OWPRs computations and methodology

Verified computer output all computer results are wrong unlessproven otherwise

Independent Review of OWPRs Methodology


35/81

Strengthening and Repairof Reinforced Concrete

Structures

Ian Wienholt

Business Development Manager


36/81

34 years of Concrete Repair and

Strengthening Experience Over 15,000 Repair Project

Over 25,000 PT Projects

1,500 Employees

22 Offices- International

UAE, UK, Saudi, China


37/81

General Repair Group:

Strengthening Division


38/81

Carbon Fiber Reinforced PolymerStrengthening


39/81

Externally Bonded FRP Sheet

550,000 psi Tensile

10x that of steel

Lightweight

Does NOT corrode

FRP Design Guidelines


40/81

FRP Design Guidelines

440.2R-02 440.2R-08

To Date:

Nationwide 15-18M sqft installedSPS 7M sqft installed on over 700 + projects

ACI 4 40.2R-08


41/81

Tension Steel

Yield

FRP carries

TENSION

What Is FRP Flexural Strengthened R/C?

Positive Moment

Wh I FRP Fl l S h d R/C?


42/81

CompressionConcrete carries

COMPRESSION

TOP

BOTTOM

SteelTension

Yield

FRP carries

TENSION

What Is FRP Flexural Strengthened R/C?

Column

Negative Moment

What Is FRP Shear Strengthened R/C?


43/81

SHEAR

What Is FRP Shear Strengthened R/C?

Installation Step 1:


44/81


Surface Grinding/Shot Blastingto Open Pores

I ll i S


45/81


Remove Dust from Surface

Before After

I ll i S 3


46/81


Epoxy Primer Application

I ll i S 4


47/81


Epoxy Putty Trowel Applied

I ll i S 5


48/81


Saturation Coat and CFRP

I t ll ti St 6


49/81


Rib Roll & Final Saturation Coat

I t ll ti St 7


50/81


Intumescent Topcoat


51/81

External Post TensioningStrengthening

E t l P t T i i


52/81

External Post Tensioning

F

F

NEW LOAD

Upliftat Deviator

Dead end

Live end


53/81

Flexural Strengthening Case Study

Environmental Overload

Tension Tension

YIELD


54/81




55/81



Form & Pump

Amplitude


56/81



Dowel Hole Drilling

High Pressure Water Blasting

Dowel Insertion


57/81



Fl l S h i C S d


58/81



Fl l S h i C S d


59/81



Fl l St th i C St d


60/81



Fl l St th i C St d


61/81



Fl l St th i C St d


62/81



43


63/81

SCC Section EnlargementStrengthening

Transfer Slab Cracking


64/81

Transfer Slab Cracking

/ I


65/81

Demo and Prep

PAM Machine in Action

Supplemental Beam Column


66/81

Supplemental Beam-Column

Connection

Mechanical Anchoring and


67/81

Mechanical Anchoring and

Reinforcement Cage

2000

UndercutAnchors

3000 HiltiStuds

SCC Pumping Anyone???


68/81

SCC Pumping Anyone???

40 Tons ofSteel

1100LF


69/81

Finished Product

185 CU YDS /

375 Tons of

Concrete


70/81

Finished Product

Estimated Cost of Beam Testing and Repairs


71/81


TestingofConcreteBeams $ 95,000.00 RadarView

Demolition/RepairWallsforTesting $ 325,000.00 EstimatebyGMS&MBP

Tearoff/PatchRoofforTesting $ 259,000.00 BakerRoofing

SubtotalTestingofConcreteBeams $ 679,000.00DeficientConcreteBeams $ 3,400,000.00 StructuralPreservationSystems

SubtotalofStructuralRepairs $ 3,400,000.00ReplaceRoofafterRepairs $ 715,000.00 BakerRoofingkerRoofing

SubtotalofStructuralRepairs&Testing $ 4,079,000.00

Contingency $ 1,423,680.00

Total $ 5,502,680.00

Questions about Concrete Beam Repairs


72/81

//



Estimated Cost of Gym Replacement


73/81

Description Budget Estimate

GeneralConditionsareincludedineachoftheitemsbelow $

Sitework&Demo $ 615,257.00

Concrete $ 1,020,386.00

Masonry $ 548,958.00

Metals $ 448,002.00

Wood&Plastics $ 9,042.00

Thermal&MoistureProtection $ 236,398.00

Doors&Windows $ 112,361.00

Finishes $ 295,720.00

Equipment $ 1,271,599.00

Elevator $ 50,000.00

Plumbing,Heat,Ventilation&AirConditioning $ 1,460,794.00

Electrical $ 876,003.00

SubTotalConstruction $ 6,944,520.00

Permits $ 12,900.00

A/EFees $ 1,041,700.00

CostEstimating $ 14,000.00

Geotechnical&StructuralTests $ 100,000.00

Engineering&SpecialTesting $ 40,000.00

QualityAssurance&TestingFees $ 17,200.00

ConstructionManagement $ 300,000.00

SubTotalFees&SoftCost $ 1,525,800.00

Total $ 8,470,320.0010%Contingentlyincludedinallitemsabove

Thisestimateincudes costto rebuildtheentirelowerlevelfoundation,structure,exteriorandinteriorwalls

Questions about Gym Replacement Estimate


74/81

, //

M B ~ ~ H ARCHITECTS AND ENGINEERS

Estimated Total Cost Repairs and


75/81

Gym Replacement

Description Budget Estimate Bid

or

Proposal

TestingofConcreteBeams $ 95,000.00 RadarView

Demolition/RepairWallsforTesting $ 325,000.00 EstimatebyGMS&MBP

Tearoff/PatchRoofforTesting $ 259,000.00 BakerRoofing

SubtotalTestingofConcreteBeams $ 679,000.001.Category1ItemsfromOWPRFacilityAssessment $ 141,000.00

General&Mech.Services

(GMS)

2.WallSettlementRepairsinthreelocations $ 66,000.00 RACConstructionCompany

3.AuditoriumRoofStructuralSystem $ 170,000.00 CSESteelErection&GMS

4.DeficientConcreteBeams $ 3,400,000.00

StructuralPreservation

Systems

CM/DesignDocuments $ 250,000.00 OWPR&MBP

SubtotalofStructuralRepairs $ 4,027,000.00ReplaceRoofafterRepairs $ 715,000.00 BakerRoofingkerRoofing

SubtotalofStructuralRepairs&Testing $ 4,706,000.00CM/DesignDocuments $ 250,000.00 OWPR&MBP

Contingency $1,423,680

GymReplacementEstimatedCost $ 8,470,320Testing,Repairs,andGymReplacement $ 14,850,000

Schedule


76/81

/

o".. .oN

".. ." . . .oN

N".. .

Repair offrom OWPR

FacilityAssessment

Repair of WallSettlement inBoiler Room,Auto Shop, and

Wood Working

Pro ctRepair

Auditorium RoofStructural Steel

Repair Deficientncrete(including

testing)GymReplacement

MB BOLYARDPECKP McDONOUGH


Work that can be Done to Improve InteriorEnvironment and Building Operations


77/81

Environment and Building Operations

Description EstimateReplaceHeating,Ventilation,AirConditioning $ 3,300,000.00

ReplaceFireAlarm $ 265,000.00

Upgrade

Plumbing

Fixtures

to

ADA

Requirements $

200,000.00

SubTotalBuildingInfrastructureUpgrades $ 3,765,000.00ReplaceVinylFloorTile $ 256,000.00

ReplaceCarpet $ 91,000.00

PaintInteriorWalls $ 418,000.00

ReplaceCeilingGridandTiles $ 418,000.00

ReplaceAuditoriumSeating $ 210,000.00

SubTotalFinishesReplacement $ 1,393,000.00ReplaceFurnitureandUpgradeTechnology $ 1,500,000.00

AddSprinklerSystem $ 838,000.00

SubTotalUpgrades $ 7,496,000.00

BHS Existing Mechanical


78/81

Heating Plant Two 250 BHP, dual fuel, Scotch Marine 2-pass fire tube boilers,original

Heating Distribution Primary pumps, 20 HP centrifugal. Secondary pumps: severalinline pumps.

Cooling Plant Two 325 Ton variable speed Centrifugal Chillers with forced draftcooling towers, new.

Cooling Distribution Primary pumps, 50 HP centrifugal. Secondary pumps: severalinline pumps.

Auditorium Four pipe with Air Handling Units.

Classrooms Four Pipe unit ventilators in exterior Classrooms. Variable Air VolumeBoxes with hot water heat in interior classrooms

Administration - Variable Air Volume Boxes with hot water heat.

Library Four pipe with Air Handling Units.

Vo. Tech Four Pipe air handling units with hot water reheat.

Band/Coral Four Pipe air handling units with hot water reheat.

Cafeteria / Kitchen - Four pipe with Air Handling Units and unit ventilators.

BHS is basically a Four Pipe Fan Coil Unit system.

Proposed Mechanical


79/81

Systems Cost

Heating

Plant

Leave

as

is.HeatingDistribution Leaveasis.

CoolingPlant Leaveasis.

CoolingDistribution Leaveasis.

Auditorium ReplaceairhandlersandprovideCO2controls. $138,400

Stage ReplaceairhandlersandprovideCO2controls. $48,100

Commons ReplaceairhandlerandprovideCO2controls. $65,000

Library ReplaceairhandlerandprovideCO2controls. $48,000

Aud.Lobby Replaceairhandler. $21,000

Vo.Tech Replaceairhandlersandprovidefancoilunitsinsmallspaces. $263,000

Band/Coral Replaceairhandlersandprovidefancoilunitsinsmallspaces. $72,000

Administration ReplacewithDOAUw/activechilledbeamsorfancoilunits. $126,000

Classrooms ReplacewithDOAUw/activechilledbeamsorunitventilators. $520,000

Ductwork Cleansupplyandreturnductsthataretoremain $200,000

Controls Provide

new

DDC

control

system $700,000Total $2,201,500

OH&PandContingencyx1.5 $3,300,000

DOAU DedicatedOutdoorAirUnit

Work that can be Done to Improve InteriorEnvironment and Building Operations


80/81

Environment and Building Operations

Description EstimateReplaceHeating,Ventilation,AirConditioning $ 3,300,000.00

ReplaceFireAlarm $ 265,000.00

Upgrade

Plumbing

Fixtures

to

ADA

Requirments $

200,000.00

SubTotalBuildingInfrastructureUpgrades $ 3,765,000.00ReplaceVinylFloorTile $ 256,000.00

ReplaceCarpet $ 91,000.00

PaintInteriorWalls $ 418,000.00

ReplaceCeilingGridandTiles $ 418,000.00

ReplaceAuditoriumSeating $ 210,000.00

SubTotalFinishesReplacement $ 1,393,000.00ReplaceFurnitureandUpgradeTechnology $ 1,500,000.00

AddSprinklerSystem $ 838,000.00

SubTotalUpgrades $ 7,496,000.00

Questions/Discussions


81/81

//

Date post:	08-Apr-2018
Category:	Documents
Upload:	buildbhs
View:	212 times
Download:	0 times