UBC Seismic Risk Assessment_Eight Buildings Final Report_Feb 7-2013

8/20/2019 UBC Seismic Risk Assessment_Eight Buildings Final Report_Feb 7-2013

1/37

G LOTMAN S IMPSON JM E NGINEERINGConsulting Engineers Consulting Structural Engineer

Suite 608 – 318 Homer Street, Vancouver, BC 604-683-0595

UNIVERSITY OF BRITISH COLUMBIASEISMIC RISK ASSESSMENT REPORT

SEISMIC ASSESSMENT OF THE FOLLOWING

HIGH & VERY-HIGH SEISMIC RISK BUILDINGS:

BLDG 017 – OLD ADMINISTRATION BUILDINGBLDG 023 – HENRY ANGUS OFFICE TOWERBLDG 052 – FRASER RIVER PARKADEBLDG 449 FOOD NUTRITION & HEALTH


2/37



TABLE OF CONTENTS

Page No.

Executive Summary………………………….……………………………………… 1

1. Introduction……………………………………………………………………. 2

2. Purpose Of Conducting The Detailed Seismic Assessment.……………. 2

3. Seismic Upgrading Philosophy For UBC Buildings In This Report..……. 3

4. Design Criteria Defining Medium Seismic Risk……………………………. 3

5. Detailed Seismic Assessment Philosophy…………………………………. 5

6. Interface With Other Building Systems……………………………………. 6

7. Detailed Seismic Assessment Results & Discussions……………………. 77.1 017 – Old Administration Building………………………………….... 77 2 023 H A Offi T 9


3/37



EXECUTIVE SUMMARY

JM Engineering conducted a detailed seismic assessment of eight buildings identified in ourprevious seismic report titled: ‘University of British Columbia Seismic Risk Assessment Report(Summary of High & Very-High Seismic Risk Buildings)’ dated June 14, 2012.

The eight buildings previously identified include the following:

Bldg 017 – Old Administration Building................. High Seismic RiskBldg 023 – Henry Angus Office Tower……………. Very High Seismic RiskBldg 052 – Fraser River Parkade………………….. High Seismic RiskBldg 449 – Food Nutrition & Health……………….. High Seismic RiskBldg 467 – Health Sciences Parkade……………... High Seismic RiskBldg 536 – Woodward Library……………………... High Seismic RiskBldg 624 – George Cunningham Addition………… High Seismic RiskBldg 864 – Wesbrook Building………………….... High Seismic Risk

Our assessment yielded the following results:

1) Buildings 449 – Food Nutrition & Health and 624 – George Cunningham Addition havebeen re-classified to Medium Seismic Risk with no structural upgrading required.

2) The remaining buildings could be reduced to Medium Seismic Risk with varying degreesof structural upgrades. Anticipated costs to achieve this re-ranking are outlined insection 8 of the report and are summarized below:


4/37


1. INTRODUCTION

JM Engineering (partnered with Glotman-Simpson Engineers) was retained by The University ofBritish Columbia to conduct a detailed seismic assessment of eight buildings identified in ourprevious seismic report titled: ‘University of British Columbia Seismic Risk Assessment Report(Summary of High & Very-High Seismic Risk Buildings)’ dated June 14, 2012.

The eight buildings previously identified include the following:

Bldg 017 – Old Administration Building................. High Seismic RiskBldg 023 – Henry Angus Office Tower……………. Very High Seismic RiskBldg 052 – Fraser River Parkade………………….. High Seismic RiskBldg 449 – Food Nutrition & Health……………….. High Seismic RiskBldg 467 – Health Sciences Parkade……………... High Seismic RiskBldg 536 – Woodward Library……………………... High Seismic RiskBldg 624 – George Cunningham Addition………… High Seismic RiskBldg 864 – Wesbrook Building………………….... High Seismic Risk

UBC is interested in understanding the scope of structural upgrading required to reduce theseismic risk of these eight buildings from high or very high seismic risk to medium seismic risk.

2. PURPOSE OF CONDUCTING THE DETAILED SEISMIC ASSESSMENT

In our previous report, we identified eight buildings which we were of the opinion might benefitfrom conducting a detailed seismic assessment


5/37


The ultimate goal of the detailed seismic assessment and this report was as follows:

i) Determine if any of the eight buildings could be re-classified to medium seismic risk levelwith no structural upgrade (ie. the existing seismic resisting system is sufficient for thebuilding to be re-classified as medium seismic risk).

ii) Determine if fixing just the seismic ‘mechanism’ in four of the buildings would besufficient to re-classify the building to medium seismic risk level.

iii) Depending on the results from goals i) and ii) above, identify the structural upgrades

required to be able to re-classify all eight of these buildings as medium seismic risk level.

iv) Provide an order of magnitude costing for implementing these structural upgrades.

3. SEISMIC UPGRADING PHILOSOPHY FOR UBC BUILDINGS IN THIS REPORT

It is our understanding that UBC’s overall goal and philosophical intent of undertaking the

seismic upgrading of these eight high and very high seismic risk buildings is to achieve thefollowing:

i) Either confirm or improve the seismic resisting capacity of the eight buildings to providea ‘reasonable’ level of safety to enable occupants to evacuate the building safely duringa medium seismic event.

ii) Given the age of the buildings economic loss of the building is not a primary concern


6/37


amount required for new buildings is acceptable. The design parameters used for new buildingdesign is that of an earthquake with a 2% chance of exceeding in any 50 year period, orequivalent to a return period of 1 in 2475 years.

In Vancouver this results in a design earthquake for new buildings with a Peak Ground Acceleration (PGA) of .46g. Other commonly used 50 year exceedance probabilities togetherwith their proportional PGA, return period, percent of force level relative to full code designrequirements, approximate Richter magnitude and approximate expected duration are:

2% in 50 Year; .46 PGA; 1:2475 return period 100% M7.5 30 seconds5% in 50 Year; .33 PGA; 1:1000 return period 70% M6.5 20 seconds10% in 50 Year; .25 PGA; 1:475 return period 50% M6 12 seconds

40% in 50 Year; .12 PGA; 1:100 return period 25% M5.3 4 seconds

By reducing the design earthquake return period to less than that required for new buildings thedesign loading is reduced making the cost and complexity of upgrading easier. However, it mustbe noted this creates a risk that the capacity of the building could be exceeded in a design eventconsistent with the 2% in 50 year event.

The seismic loading specified by National Research Council Canada publication "Guidelines for

Seismic Evaluation of Existing Buildings" dated 1992 used for the structural survey of abuildings seismic system equates to approximately 30% of the current code requirements for anew building with similar structure. As noted in the table above this equates to a designearthquake with a return period of 1:100. It has generally been accepted locally that this is anappropriate force level on which to base an S3 level seismic upgrade.

From a design assessment point of view, we defined the various seismic risk levels for UBCBuildings as follows:


7/37


Using the above criteria, the medium risk design check included the following:

Satisfy 1:100 yr earthquake which equates to approximately 30% of the current codeseismic base shear Verify no seismic mechanism exists Check interstorey and total building drift < 1 ½% Confirm low strains in concrete and reinforcement Check moment capacity/demand ratios less than or equal to shear capacity/demand

rations for ductile response Check compression is not overstressed in the shear walls or non-seismic resisting

column elements Satisfying the above implies that a brittle seismic failure will not occur before 30% of

seismic base shear Therefore classify building as medium seismic risk

5. DETAILED SEISMIC ASSESSMENT METHODOLOGY

Due to the existing buildings age and the low to non-existent ductility inherent in the existing

framing and reinforcement detailing, we used the following design parameters in all seismicassessments:

F’c = 25 Mpa (concrete)Fy = 300 Mpa (reinforcement)Rd=1.5Ro=1.3I 1 0


8/37


i) Seismic base shear capacity/demand ratio > 30%ii) Material strains less than identified in the table aboveiii) Interstorey drifts < 1 ½ %

iv) Seismic moment capacity/demand rations less than seismic base shearcapacity/demand ratios

Then the building was classified as having satisfied the criteria for medium seismic risk.It quickly became apparent that seismic ‘mechanisms’ failed to satisfy all the above criteria. Inthese situations, the mechanism was ‘upgraded’ with additional shear walls or other structuralelements deemed appropriate. The Etabs model was updated and then the building was runagain. This became an iterative process until the above criteria was satisfied. When this wasachieved, we had an understanding of the upgrading required to satisfy the medium seismic risk

design criteria.

Similarly, a building with no apparent seismic mechanism that failed to meet the mediumseismic risk design criteria meant the building’s seismic resisting system was deficient andrequired upgrading. After reviewing the seismic base shear capacity/demand ratios, weintroduced new seismic elements as necessary and re-ran the Etabs model making adjustmentsas necessary until the building satisfied the medium seismic risk design criteria.

This process was repeated for all eight buildings.

6. INTERFACE WITH OTHER BUILDING SYSTEMS

Since our mandate was to identify the most direct structural upgrade required to bring thebuilding to a ‘Medium’ Seismic Risk level, we did not consider the interface and implications ofthe architectural mechanical or electrical systems during the seismic assessment


9/37


7. DETAILED SEISMIC ASSESSMENT RESULTS & DISCUSSIONS

7.1 BUILDING 017 – OLD ADMINISTRATION BUILDING

7.1.1 Framing Description

The Old Administration Building is a 2 storey with partial full basement and partialcrawlspace structure constructed with timber stud wall and timber floor joist/beamframing.

The building has seen several renovations and additions. The west addition includedsome structural steel OWSJ and metal deck roof framing supported on steelbeams/posts.

The exterior walls are, as far as we know, stucco on lath/plaster on stud framing. Thereare no known timber shear walls inside the building. There are some block walls at the

junction of one addition, but little is known of the extent. All interior walls are covered

with drywall. Most of the ceiling is drywall.

7.1.2 Reason For Initial High Seismic Risk Ranking

There are no defined shear walls, and the west addition contains a soft storey by way ofthe clerestorey windows that existing all along the west basement wall returning 20ft onthe north and south walls


10/37


iii) The beam/column ties were not checked in the crawlspace, but based on ourexperience with other buildings at UBC of similar age, we would assume there

are no beam/column ties.iv) The existing floor diaphragms are adequate.

7.1.4 Structural Upgrading Required

Refer to the attached sketch SSK-017-01 for the recommended structural upgrades.These include the following:

i) Install new timber sheathed shear walls with hold downs all along the interior ofthe perimeter walls (existing windows to be maintained).

ii) Introduce new timber sheathed shear walls in the main interior corridor full heightincluding hold downs and footings as required.

iii) Eliminate some of the basement clerestorey windows and infill with new timbershear walls matching the window profile above.

iv) Tie the beam/columns and the column/footing connections in the crawlspace.

7.1.5 Conclusions

The building is deficient in resisting the seismic base shear in both directions due to thelack of defined shear walls. The addition of timber sheathed defined shear walls in thebuilding as noted including hold downs, the remedial re-framing at the clerestorey, andthe beam/column tying within the crawlspace will improve this building, in our opinion, tothe point where it can be re-ranked as MEDIUM SEISMIC RISK.


11/37


7.2 BUILDING 023 – HENRY ANGUS OFFICE TOWER


The Henry Angus Office Tower is a 9 storey office building consisting of 8 storeys ofreinforced concrete flat plate slabs supported on reinforced concrete stair and elevatorwalls, interior concrete columns and pre-cast mullion perimeter columns. The top floor isframed with structural steel.

7.2.2 Reason For Initial Very High Seismic Risk Ranking

This office tower’s seismic resisting system consists of non-ductile reinforced concreteshear walls. The elevator and stair concrete walls are continuous full height, howeverthere are four perimeter north/south walls that are discontinuous and only start at thesecond floor.

Not only is there a lack of reinforced concrete shear walls in the north/south direction,

but the ‘very high’ seismic risk ranking was warranted because of the ‘soft storey’seismic failure mechanism that existed at the second floor level where the four perimetershear walls started. These walls are supported on small non-ductile column elements atthe ground floor level which were expected to perform poorly in a seismic event.

There was also concern about possible pre-cast mullion failure if the interstorey driftswere large.


12/37


ii) The maximum concrete strain was 0.00171


13/37


7.3 BUILDING 052 – FRASER RIVER PARKADE


The Fraser River Parkade consists of a 3 storey concrete building comprised of pre-castdouble tee planks and pre-cast beams supported on pre-cast walls. The interior wallsform part of the ramp framing. There are also four stair cores located at each corner ofthe building.

Also of importance is that there is a topping on the pre-cast planks creating the slab

diaphragm. There are nominal embedded plate connections visible between the pre-cast planks and the pre-cast walls.

7.3.2 Reason For Initial Very High Seismic Risk Ranking

The parkade building is ranked ‘very high’ seismic risk because of the short length of the6 north/south non-ductile walls.

The embedded plate connections between the slab diaphragm and the beams and wallsare nominal to non-existent which may result in pre-cast elements falling off supportingmembers. The ability of the slab diaphragm to transfer shear into the walls wasquestionable.

Also the slab diaphragm topping slab is jointed on a regular grid of approximately 20fto/c The depth of jointing is unknown but if it extends down to the top of the pre-cast


14/37


ii) The maximum concrete strain was 0.00178


15/37


7.4 BUILDING 449 – FOOD NUTRITION & HEALTH


The Food, Health & Nutrition building consists of a 3 storey reinforced concrete buildingwith one basement level. The reinforced concrete flat plate slabs are supported on aseries of concrete walls and long rectangular columns. The slab floor plate increases indimension on one side of the building increasing at each level which introducessignificant P-delta effects onto the long rectangular columns.


This building’s seismic resisting system consists of limited ductile reinforced concreteshear walls and was ranked ‘high’ seismic risk in our previous report.

The ranking was justified by the irregular ‘L’ shaped building layout, the offsetcantilevered building profile generating large P-delta effects, and the non-continuity of

several stair walls within the center portion of the building.

All these factors led us to believe there may be a potential for large torsional forces atthe ends of the building and the potential for significant interstorey drifts. As well, thecapacity of the existing walls was a concern.

This building did not have an obvious seismic ‘mechanism’. It was considered asgenerally lacking in seismic capacity for the points noted above


16/37


7.4.4 Conclusions

The building satisfies the minimum design criteria for medium seismic risk ranking andcan therefore, in our opinion, be re-ranked as MEDIUM SEISMIC RISK with no structuralupgrading.


17/37


7.5 BUILDING 467 – HEALTH SCIENCES PARKADE


The Health Sciences Parkade consists of a 4 storey building comprised of reinforcedconcrete one way slabs and beams supported on concrete walls and columns.

There are six short interior concrete shear walls in the north/south direction and none inthe east/west direction. There are also four stair cores located at each corner of thebuilding.

This parkade has a unique seismic lateral resisting system. The seismic systemconsists of the short concrete shear walls in the north/south direction, and a folded platediaphragm system incorporating the ramp slabs to transfer the shears down to thebasement foundation walls in the east/west direction.


The parkade is ranked ‘high’ seismic risk primarily because of the lack of walls or lengthof walls in the north/south direction. The folded plate system in the east/west directionwas also considered unique and could not be considered acceptable without conductinga detailed seismic analysis on the diaphragm forces.

Also short column effect was also considered possible along the ramp supportingcolumns


18/37


The folded plate diaphragm was found to be able to resist the forces generated from30% of the base seismic shear.

The small interstorey drifts limited the forces in the short columns along the ramp. Shortcolumn effect is not an issue in this parkade.



i) The six short north/south walls require the addition of carbon fibre reinforcement.New tension elements are required each end on four of the walls. These wallswill also require soil anchors.

7.5.5 Conclusions

The building is deficient in resisting the seismic base shear in the north/south direction.The application of carbon fiber reinforcement and select tension elements with soilanchors as noted above on the short walls will improve this buildings seismic capacity, inour opinion, to the point where it can be re-ranked as MEDIUM SEISMIC RISK.


19/37


7.6 BUILDING 536 – WOODWARD LIBRARY


The Woodward Library consists of a 3 storey building comprised of the original buildingand an addition literally saw toothed into the original building. The combined building isconstructed with reinforced concrete slabs utilizing drop panels and column capitalssupported on reinforced concrete walls and columns.


This building’s seismic resisting system consists of non-ductile reinforced concrete shearwalls. The shear walls include stair cores located at each perimeter corner, and onecentral stair and elevator.

This building was ranked ‘high’ seismic risk due to the arrangement of the shear wallsaround the perimeter and in inability of the slab diaphragm to engage these walls.

Because of the arrangement of the shear walls within the floor plate, the building lackssufficient shear walls. In addition, we were concerned the diaphragm contained highlocalizes drag strut forces which were not adequately resolved.

7.6.3 Results From Seismic Analysis

The existing building’s slab diaphragms walls and column elements were modeled in

G S


20/37




i) Add carbon fiber reinforcement on one side of the existing concrete walls notedin the attached plan full height from top of footing to u/s roof slab.

ii) Add structural steel drag struts anchor bolted to the u/s of the slab and to theshear walls at the locations shown on the plan. This would be required at eachfloor and roof slab.

7.6.5 Conclusions

The building is deficient in resisting the seismic base shear in the east/west direction andtransferring this shear into the concrete shear walls. With the application of carbon fiberreinforcement and addition of steel drag struts as noted above, this building could, in ouropinion, be re-ranked as MEDIUM SEISMIC RISK.

G S JM E


21/37


7.7 BUILDING 624 – GEORGE CUNNINGHAM ADDITION


The George Cunningham Addition building consists of a 4 storey reinforced concretestructure constructed with one way concrete slabs supported on concrete walls andcolumns. There is a deep perimeter spandrel beam at the slab edge all around thebuilding.


This building’s seismic resisting system consists of non-ductile reinforced concrete shearwalls. The ‘high’ seismic ranking was due to the lack of shear walls and the short lengthof these shear walls in the north/south direction.

In addition, the building contains a seismic ‘mechanism’ in the way of short columns as aresult of the deep spandrel beams.

7.7.3 Results From Seismic Analysis

The existing building’s slab diaphragms, walls, and column elements were modeled inEtabs. In particular, the deep spandrel beams were carefully modeled as well as theperimeter columns to check the forces and drifts in these columns.

G S JM E


22/37


7.8 BUILDING 864 - WESBROOK


The Wesbrook building is a 3 storey structure with one basement constructed withreinforced concrete rib /beam slab system supported on reinforced non-ductile concretewalls and columns.

The building is an irregular ‘V’ shape with long slab diaphragms out to the ends of thewings. The center block contains the larger volume lecture theatres. Deep spandrel

beams form the edge of the slabs creating possible short columns.


The Wesbrook building’s seismic resisting system consists of non-ductile reinforcedconcrete shear walls. The shear walls reinforcement is not called up on the drawings soassuming minimum reinforcement, the non-ductile walls were considered inadequate inshear, especially at the ends of the wings which would experience significant torsionalforces.

In addition, the ‘high’ seismic risk ranking was warranted due to the possible shortcolumn affect assuming large interstorey drift at the ends of the wings, as well asdiaphragm span issues.

G S JM E


23/37




i) Add carbon fiber reinforcement on one side of the existing concrete walls notedin the attached plan full height from top of footing to u/s upper most slab.

This upgrade is based on the assumption the existing wall reinforcement is minimumhorizontal and vertical as required by code. If, for example, the wall reinforcement wastwice minimum, then no carbon fibre reinforcement would be required.

7.8.5 Conclusions

We recommend the reinforcement in existing select walls be verified. Assumingminimum reinforcement, the building is deficient in resisting the seismic base shear inseveral concrete shear walls, or the shear capacity/demand ration was lower than themoment capacity/demand ratio. With the application of carbon fiber reinforcement asnoted above, this building could, in our opinion, be re-ranked as MEDIUM SEISMICRISK.

G S JM E


24/37


8. ESTIMATED ORDER OF MAGNITUDE COSTING FOR SEISMIC UPGRADING

The following provides an order of magnitude costing for the proposed structural seismicupgrades to achieve ‘medium’ seismic risk. It is important to note the following:

i) The proposed upgrades do not take into account the architectural seismicupgrade feasibility in implementing the upgrades. The upgrades are the moststructurally efficient method of achieving the upgrade.

ii) Due to the nature of the proposed seismic upgrades, we assume the mech/eleccosts are nominal.

iii) Due to the nature of the proposed seismic upgrades, we assume the typicalarchitectural costs are essentially limited to select demolition and reinstatingfinishes.

iv) The cost estimates provided do not assume any soft costs, expenses, taxes, OH,etc.

G S JM E


25/37


Estimated Order Of Magnitude Seismic Upgrading Costs

BuildingNo.

Building NameSeismic Upgrade Costs To Achieve Medium Seismic

Risk

Structural ($) A/M/E ($) Total ($)

017 Old AdministrationBuilding

225,000. 235,000. 465,000.

023 Henry Angus OfficeTower

425,000. 250,000. 675,000.

052 Fraser River Parkade 300,000.(Excluding

Topping Issue)

--- 300,000.(Excluding

Topping Issue)

449 Food Health Nutrition --- --- ---

GLOTMAN SIMPSON JM ENGINEERING


26/37


9. COMMENTS ON ACHIEVING FULL SEISMIC UPGRADING

In all eight buildings, the scope of work to achieve a full seismic upgrade which is compliant tothe 2012 BC Building Code seismic base shear requirements is significant.

It is our opinion having modeled each building that all six of the ‘buildings’ would requireessentially a full demolition scenario with not just carbon fiber upgrades of select walls, but theneed to add new concrete shear walls or steel x-bracing, new soil anchors, and the installationof new drag struts to augment the existing seismic resisting system.

Similarly, the two ‘parkades’ would also require the addition of new seismic resisting elementssuch as concrete shear walls or steel bracing. Due to the inherent open nature of the parkades,and the less stringent aesthetics and exiting issues, this may be achieved much easier than witha building (ie the seismic elements might be added to the perimeter of the parkade).

Therefore the cost of a full seismic upgrade is many times the cost of the upgrades identified inthis report in order to achieve a partial seismic upgrade which improves building performance toa Medium Seismic Risk level only.

If you have any questions, please do not hesitate to contact me directly.

Yours Very TrulyJM Engineering

GLOTMAN SIMPSON JM ENGINEERING


27/37


APPENDIX

SSK’SSTRUCTURAL PLANS


28/37

NEW TIMBER SHEATHED SHEAR WALLS WITH HOLDDOWNS INSTALLED ON THE INTERIOR FACE OF THE

EXTERIOR WALLS OR ON EITHER SIDE OF T HEINTERIOR WALLS. SHEAR WALL TO EXTEND TOEXISTING FOUNDATION WALLS OR TO NEW

FOOTINGS IN THE CRAWLSPACE.CLERESTOREY WINDOWS TO BE REMEDIATED TOFOLLOW THE WINDOW OPENINGS IN THE WALLS

ABOVE. SHEAR WALLS WORK AROUND THEEXISTING WINDOW OPENINGS.

SSK-017


29/37

NEW TIMBER SHEATHEDSHEAR WALL ALONG ONESIDE OF THE INTERIORCORRIDOR INCLUDINGNEW FOOTINGS IN THECRAWL SPACE.

TIE ALL BEAM/ COLUMNCONNECTIONS INTHECRAWLSPACE

SSK-017-02


30/37

NEW TIMBER SHEATHED SHEARWALLS TO CONCRETE FOOTINGS/ WALLS INCLUDING HOLD DOWNSINSTALLED ON THE INSIDE FACE OFTHE PERIMETER WALLS TYPICALNOTED THUS (SEE PLAN AS WELL).

REVISED CLERESTROEYFRAMING TO ACCOMMODATENEW SHEAR WALLS ANDELIMINATE THE SOFT STOREYISSUE. TYPICAL SHOWN THUS.

SSK-017


31/37

NEW REINFORCED

CONCRETE WALLS AND

FOOTINGS INCLUDING SOIL

ANCHORS ALL FOUR

CORNERS.

NEW REINFOIRCED

CONCRETE SHEAR

WALLS GROUND TO U/S

3RD TYPICAL ALL FOUR

CORNERS

SSK


32/37

THESE CONCRETE WALLS EXIST

STARTING THE THE SECOND

FLOOR. WE WOULD NEED TO

AUGMENT THESE WALLS TO

ENGAGE THEM FULL HEIGHT TO

THE U/S OF THE 3RD FLOOR AND

IMPROVE THE SLAB CONNECTIONAT LEVEL 2. TYPICAL ALL FOUR

CORNERS.

ADD STEEL TENSION

ELEMENTS AT THE

EXISTING WALL ENDS UP

TO U/S OF LEVEL 6

TYPICAL ALL FOUR

CORNER WALLS EACH

END

SSK-0


33/37

CARBON FIBER ONE SIDE OF

EACH WALL CLOUDED THUSFULL HEIGHT. IMPROVE

SHEAR CONNECTIONSBETWEEN PRE-CAST WALLELEMENTS AT ALL JOINTS.

EXPOSE AND IMPROVE PRE-

CAST WALL CONNECTION TOFOOTINGS.

REQUIRED ANCHOR BOLTEDTO SLAB AND WALLS TO

IMPROVE SHEAR TRANSFERINTO THE PRE-CAST WALLS.TYPICAL ALL SIX WALLS BEING

CARBON FIBER REINFORCED.

/ COLUMN

CONNECTIONSTYPICAL

SSK-052-01

INVESTIGATE THE JOINTING INTHE TOPPING SLAB TO VERIFY

IT'S ABILITY TO ACT AS ADIAPHRAGM. IMPROVE ASNECESSARY. TYPICAL ALL

LEVELS.


34/37

CARBON FIBERTHESE WALLSON GRIDS 3 AND8 FULL HEIGHT (6WALLS TOTAL)

IMPROVE BEAM/ COLUMNCONNECTIONSTYPICAL ALLLEVELS

ADD STEELDRAG STRUTSAS REQUIREDCONNECTINGSLAB TO THEWALLS TYPICAL

SSK-052-02


35/37

ADD CARBON FIBRE

REINFORCEMENT ONE SIDE

OF EACH WALL FULL

HEIGHT FROM TOP OF

FOOTING TO U/S ROOF

SLAB TYPICAL 6 WALLS.

ADD STEEL TENSION ELEMENTS

AND SOIL ANCHORS AS

REQUIRED AT BOTH ENDS OF

FOUR WALLS AS NOTED THUS

FROM FOUNDATIONS TO U/S OF

ROOF LEVEL.

- -


36/37

CARBON FIBER ONESIDE OF THESE WALLS(FOUR TOTAL) FULL

HEIGHT TYPICALSHOWN THUS

ADD STEEL DRAG STRUTSANCHOR BOLTED TO THEUNDERSIDE OF THE SLAB AND

THE SIDE OF THE CONCRETESHEAR WALLS TYPICAL SHWONTHUS. ASSUME THIS IS

REQUIRED ON ALL FLOORS ANDROOF SLAB.

SSK-536-01


37/37

ADDCARBONFIBREONONE SIDEOF

THISWALL FULL HEIGHT. APPEARS

TO HAVEDUCTSONONE SIDEAND

ELEVATORON INSIDE...MAYBE

EASIERTO LOCKOFF THE ELEVATOR

ANDDO IT FROM THE INSIDETYPICAL

TWO ELEVATORS.

ADDCARBONFIBER

REINFORCEMENT ONTHESE

WALLSFROM TOPOFFOOTINGSTO TOP OF THE

WALL - WHICHDOESNOT GO

UPTO THEROOF.TYPICAL

FORALL WALLSEXCEPT AT

THEELEVATORS

SSK-864-01

Documents

UBC Seismic Risk Assessment_Eight Buildings Final Report_Feb 7-2013