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IntroductionIntroductionl Used to anchor into concrete,
masonry, stonel With time, the evolution of
anchors have led to differentdesigns
l More than one anchor type may besuitable for a particular purpose
l Thus there are some salientfeatures which need to beexamined before choosing anyanchor
Salient features whileSalient features whilechoosing an anchorchoosing an anchor
l Base material
l Design
l Load
Base MaterialBase Materiall Material being anchored to
l Can be concrete, brick, tile block, stoneetc
l The type of fastener for the applicationis determined by it
l Stone & concrete has high load carryingability (due to its strength and mass)
l Other base material, has much less massto anchor to, thus much less strength
Note: The holding power and the strength of the basematerial need to be known for proper anchoring
Type of Base MaterialType of Base Material
CohesiveCohesiveFine grainedsoil. E.g. clay
NonNon--cohesivecohesiveCoarse grainedsoil. E.g. sand
Each type can be further subdividedinto 3 categories
1. Based on the origin of the soil2. Method of deposition3. Structure
DesignDesignl Proper size hole for maximum
efficiency of the mechanicalanchor
l Proper spacing between theanchors
l Compressive strength of the basematerial
l Distance of the surface from theembedded end of the anchor
LoadsLoadsLoad types depending on thedirection
l Tension– applied parallel to the length of the anchor
– loads stress the fastener and the base material
l Shear– perpendicular to the length of the anchor
– the depends on the anchor strength
l Complicated– Combination of tension and shear
– Resultant load in some other direction
LoadsLoadsLoad Types depending on load
movementl Static
– Non moving loads
l Dynamic– Vibration etc
– Causes the loosening of the anchor
The load bearing of the anchor depends onl Expansion force of the anchorl Strength of the base material
Types of AnchorsTypes of Anchorsmanufactured by usmanufactured by us
l Helical Anchor
l Rock Anchor
l Expanding Anchors
l Cross Plate Anchors
Helical Anchor/ HelicalHelical Anchor/ HelicalPiersPiers
l Design Features
l Application
l Advantages
Design featuresDesign featuresl Consist of central shaft made up
of square or round rod– transmits torque during installation
– transfers axial loads to the helical plates.
– also provide the resistance to lateralloading
l Helical shaped circular steelplate welded to the shaft– Helical plates constructed with controlled
pitch
– Causes more soil resistance during normalloading
Round Rod and SquareRound Rod and SquareRodRodl Round Rod Helix Anchor/ No-
Wrench Screw Anchor– Can be installed by hand or machine
– Much be installed at greater depth to reachfirm soil
l Square Shaft / Wrench Type ScrewAnchor– Designed for heavy guy loading
– Extension Shaft is coupled for installationat proper depth
ApplicationsApplicationsl Used as soil anchors
– for retaining walls
– to resist wind loads for tall structures
l Used for building foundations– for new structures
– under pins for existing structures
– as support for broad walks, light posts etc
AdvantagesAdvantagesl rapid installation
l immediate loading capability andresistance to both uplift andbearing loads
l high capacity application
l limited access installation
DesignDesignl Designed of a threaded rod with
turn buckle and two opposingwedge
l The rotation of the turn buckleforces the wedge against thesides of the rock, locking theanchor in place.
l Load increases the wedging forceand the holding power.
ApplicationsApplicationsl Used in bare solid rocks
l Used in thin soil with solid rocknear the surface
l The anchor expands and wedgesagainst the solid wall of the rock
AdvantagesAdvantages
l Provide easy and efficient meansof installation
l the greater the pull on the rod,the harder the anchor becomeswedged
l No concrete needed.l Saves timel Reduces laborl Cost -effective
Design FeaturesDesign Features
l The multi-blade, one-piece top plated– expands upon impact to form a cone shaped square
– distributes the anchor's holding power over a widearea
– builds up compression against an inverted pyramidof earth
l Base plate– Supports the blades at the center
– Distributes the load uniformly over the blades
l Rib– Provides additional reinforcement and strength
ApplicationApplicationl Compacted clay and gravel mixed,
shale, broken rock, hardpan
l Compacted sand, clay pan,compacted gravel.
l Loose sand, gravel and clay,compacted coarse sand
AdvantagesAdvantages
l Can be used in a variety of basematerials
l Provide efficient and easyinstallation
l Cost -effective
DesignDesign
l Simple design
l 2 – plates– made up of structural steel
– Welded at perpendicular to each other
– Plate edges are flanged to resist creeping.l Rib
– for reinforcement
– provides extra strength
ApplicationApplicationl Compacted clay and gravel mixed
broken rockl Compacted sand, compacted
gravell Loose sand, gravel and clayl Clay loam, damp clay, loose
coarse sandl Silt loam, loose sand fines
AdvantagesAdvantages
l Can be used in a variety of basematerials
l Provide efficient and easyinstallation
l Cost -effective
ConclusionsConclusionsl Further research are being
carried out for betterperformance of the anchors
l Extensive tests are carried outto deliver quality products
l Installation manual for each ofthe anchors are also supplied foreasy and efficient installation
For details regarding the tests, installation, research oranything concerning the anchors , do contact us.
