Earthquake Shear Wall Divita

7/30/2019 Earthquake Shear Wall Divita

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SHEAR WALL


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SHEAR WALL SHEAR WALL IS A VERTICAL

STRUCTURALELEMENT USED TORESIST LATERAL/HORIZONTAL/SHEARFORCES PARALLEL TO THE PLANE OFTHE WALL

IT HAS PROVEN TO BE THE MOSTRELIABLE IN RESISTING EARTHQUAKELOADS.

THE WALLS MAY BE PLACED IN THE

FORM OF ASSEMBLIES SURROUNDINGTHE LIFT SHAFTS OR STAIR WELLS. THEWALLS ARE STRUCTURALLYINTEGRATED WITH ROOFS/FLOORS ANDOTHER WALLS THEREBY GIVING ATHREE DIMENSIONAL STABILITY FORTHE BUILDING STRUCTURE


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COMPARASION TO LOAD BEARING AND

RCC FRAME STRUCTURE

RCC FRAME STRUCTURE ISSLENDER BUTDUCTILE.THOUGH

ACHIEVING EARTHQUAKERESISTANT DESIGN IS NOTPOSSIBLE EVERYTIME.

SHEAR WALL CANWITHSTAND EARTHQUAKES

BECAUSE THEIRSUPPORTING AREA WITHREFERENCE TO TOTAL PLANAREA OF THE BUILDING IFCOMPARATIVELY MOREUNLIKE THE RCC FRAMEDSTRUCTURE

LOAD BEARING MASONRYIS VERY BRITTLEMATERIAL. COLLAPSES

INSTANTLY DURINGEARTHQUAKES


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DESIGN OF A SHEAR WALL

DOOR OR WINDOW OPENINGSCAN BE PROVIDED IN SHEARWALLS, BUT THEIR SIZE MUST BESMALL TO ENSURE LEASTINTERRUPTION TO FORCE FLOWTHROUGH WALLS.

OPENINGS SHOULD BESYMMETRICALLY LOCATED.

SHEAR WALLS ARE MOREEFFECTIVE WHEN LOCATED

ALONG EXTERIOR PERIMETER OFTHE BUILDING

WHILE RECTANGULAR CROSS-SECTION IS COMMON, L- AND U-SHAPED SECTIONS ARE ALSOUSED


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CONCRETE SHEAR WALL

SHEAR WALLS ARE EASY TO CONSTRUCT, BECAUSEREINFORCEMENT DETAILING OF WALLS IS SAME AS RC FRAMES

THEY ARE COST EFFECTIVE.

THESE WALLS GENERALLY START AT FOUNDATION LEVEL AND

ARE CONTINUOUS THROUGHOUT THE BUILDING HEIGHT. ONLY

THEN IT CAN TRANSFER LOAD TILL FOUNDATION.

THEIR THICKNESS CAN BE AS LOW AS 150MM, OR AS HIGH AS400MM IN HIGH RISE BUILDINGS.

SHEAR WALLS ARE USUALLY PROVIDED ALONG BOTH LENGTH

AND WIDTH OF BUILDINGS.


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CONSTRUCTION DETAILS STEEL REINFORCING BARS

ARE TO BE PROVIDED INWALLS IN REGULARLY SPACEDVERTICAL AND HORIZONTALGRIDS .

THE VERTICAL ANDHORIZONTALREINFORCEMENT IN THEWALL CAN BE PLACED IN ONEOR TWO PARALLEL LAYERSCALLED CURTAINS.

HORIZONTALREINFORCEMENT NEEDS TOBE ANCHORED AT THE ENDSOF WALLS.

THIS VERTICALREINFORCEMENT SHOULD BEDISTRIBUTED UNIFORMLY

ACROSS THE WALL CROSS-SECTION.


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BOUNDARY ELEMENTS AND STILT PARKING

END REGIONS OF A WALL WITH

INCREASED CONFINEMENT ARE

CALLED BOUNDARY ELEMENTS

RC WALLS WITH BOUNDARY

ELEMENTS HAVE

SUBSTANTIALLY HIGHER

BENDING STRENGTH AND

HORIZONTAL SHEAR FORCE

CARRYING CAPACITY

PARKING

INCASE OF STILT

CONSTRUCTION ,SHEAR WALLS

MUST BE STRATEGICALLY

DESIGNED TO GIVE PARKINGSPACE


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REINFORCED HOLLOW CONCRETE BLOCK MASONRY (RHCBM) CONSTRUCTION TECHNIQUE IS AN

OPTIMAL SOLUTION, BOTH FROM THE

ANGLES OF COST EFFECTIVENESS AND

STRUCTURAL SAFETY.

RHCBM WALLS ARE CONSTRUCTED BYREINFORCING THE HOLLOW CONCRETE

BLOCK MASONRY, BY TAKING ADVANTAGE

OF HOLLOW SPACES AND SHAPES OF THE

HOLLOW BLOCKS.

WITHOUT INVOLVING

ADDITIONAL COSTS AND ANY

SPECIAL SKILLS, MATERIALS,

EQUIPMENT,

MACHINERY.

IT IS ADVISABLE TO PROVIDE MINIMUM

12MM ROD IN EVERY CORNER OF A

WALL PANEL AND AT EVERY FREE END

OF THE WALL PANEL.

AT A SPACING OF MAXIMUM 1.2M,MINIMUM ONE ROD OF 8MM IS TO BE

PROVIDED.

PROVIDE REINFORCEMENT ALL

AROUND ANY OPENINGS SUCH AS

WINDOWS AND DOORS.

PROVIDE HORIZONTAL

REINFORCEMENT AT FLOOR LEVEL, SILL

(WINDOW BOTTOM) LEVEL, LINTEL

(WINDOW TOP) LEVEL, AND ROOF

LEVELS IN EACH STOREY.


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CLASSIFICATION OF SHEAR WALLS

1. SIMPLE RECTANGULAR

TYPES AND FLANGED

WALLS (BAR BELL TYPE)

2. COUPLED SHEAR WALLS

3. RIGID FRAME SHEAR

WALLS

4. FRAMED WALLS WITH IN

FILLED FRAMES

5. COLUMN SUPPORTED

SHEAR WALLS

6. CORE TYPE SHEAR WALL.


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PUNCTURES IN

SHEAR WALL

From the illustrationabove, it can be seen thatif a door is placed in theshear wall, the unit shear(v) increases. The same

is true for windows orother openings in theshear wall. It can also beshown that a longer shearwall will have a lowerunit shear than a shorterone, thus permitting theuse of thinner sheathingand fewer (or smaller)nails.


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IN MIDPLY SHEAR WALL DESIGN, ONEPLY OF SHEATHING MATERIAL ISPLACED AT THE CENTER OF

THE WALL BETWEEN A SERIES OF

PAIRS OF STUDS ORIENTED IN A 90

ROTATED POSITION RELATIVE TOTHOSE IN STANDARD SHEARWALLS

PLYWOOD, TO TRANSFER SHEAR FORCES

CHORDS, TO RESISTTENSION/COMPRESSION GENERATED BY

THE OVER TURNING MOMENTS BASE CONNECTIONS TO TRANSFER

SHEAR TO FOUNDATIONS.


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STEEL SHEAR WALL Advantages of Steel Plate

Shear Wall to Resist LateralLoads:

The system, designed and detailedproperly is very ductile and hasrelatively large energy dissipationcapability. As a result, steel shear

walls can be very efficient and

economical lateral load resistingsystems.

The steel shear wall system hasrelatively high initial stiffness, thus

very effective in limiting the drift.

Compared to reinforced concreteshear walls, the steel shear wall ismuch lighter which can result in less

weight to be carried by the columnsand foundations as well as lessseismic load due to reduced mass of

the structure.


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STEEL SHEAR WALL V/S CONCRETE SHEAR WALL

Due to relatively small thickness of steel plate shear walls comparedto reinforced concrete shear walls, from architectural point of view,steel plate shear walls occupy much less space than the equivalent

reinforced concrete shear walls. In high-rises, if reinforced concreteshear walls are used, the walls in lower floors become verythick and occupy large area of the floor plan.

Compared to reinforced concrete shear walls, steel plate shear wallscan be much easier and faster to construct when they are used inseismic retrofit of existing building.

Steel plate shear wall systems that can be constructed with shopwelded-field bolted elements can make the steel plate shear wallsmore efficient than the traditional systems. These systems can alsobe very practical and efficient for cold regionswhere concreteconstruction may not be economical under very low temperatures.


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CRACKS

DURING LARGE SEISMIC EVENTS,

SHEAR CRACKING AND DISTRESS

CAN OCCUR AROUNDOPENINGS IN CONCRETE SHEAR

WALLS AND IN SPANDREL BEAMS

AND LINK BEAMS BETWEEN SHEAR

WALLS

SHEAR FAILURE CAN OCCUR AT

WALL CONSTRUCTION JOINTS

USUALLY AT A LOAD LEVELBELOW THE EXPECTED CAPACITY.

BENDING FAILURES CAN RESULT

FROM INSUFFICIENT VERTICAL

CHORD STEEL AND INSUFFICIENT

LAP LENGTHS AT THE ENDS OF THE

WALLS


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ISOLATED SHEAR WALL for RETROFITTING

ISOLATED SHEAR WALLS CAN BE USED TO PROVIDE STABILITY TO THEBUILDING FRAME, WHERE THE POSITIONING OF THE BUILDING CORESREQUIRES ADDITIONAL STABILITY STRUCTURES.

BI-STEEL PANELS ARE MANUFACTURED AND FABRICATED INTO SHEAR WALLMODULES OFF-SITE, THEN TRANSPORTED TO THE PROJECT SITE WHERETHEY ARE QUICKLY AND ACCURATELY ASSEMBLED. ONCE IN POSITION, THE

PANELS ARE FILLED WITH CONCRETE TO CREATE A ROBUST STRUCTUREWITH OUTSTANDING STRENGTH AND STIFFNESS.

BENEFITS

FASTER TO BUILD

HIGHLY FLEXIBLE

IMPROVED EFFICIENCY DUE TO BETTER BUILD SEQUENCE ANDREDUCED SITE CONGESTION

GREATER ACCURACY

IMPROVED INTERFACE

WITH ADJOINING STEELWORK


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SEISMIC-STRENGTHENING TECHNOLOGIES

JACKETING OF BOUNDARYELEMENTS USING CAST-IN-SITUREINFORCED CONCRETE (FOR

WALLS WITH INADEQUATE

THICKNESS ANDREINFORCEMENT)

CRACK INJECTION WITH EPOXYRESIN, GROUT, OR MORTAR(FOR REPAIRING THE CRACKS INSHEAR WALLS AND COUPLING

BEAMS)

ADDITION OF NEW REINFORCEDCONCRETE SHEAR WALLS (USEDIN BUILDINGS WITHINADEQUATE AMOUNT OFSHEAR WALLS IN ONEDIRECTION)


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REFERENCES

www.bmtpc.org

www.nicee.org

http://www.wisegeek.com/what-is-a-shear-wall.htm

THANK YOU

PRESENTED BY:

DIVITA DUGAR
http://www.bmtpc.org/http://www.nicee.org/http://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.wisegeek.com/what-is-a-shear-wall.htmhttp://www.nicee.org/http://www.bmtpc.org/

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Earthquake Shear Wall Divita