Anclajes helicoidales

HELICAL ANCHORS & FOUNDATIONS

HELICAL C SCREW SC W ANCHORS C O S AND FOUNDATIONS IN SOIL

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Historical Perspective 

1st Recorded use of a Screw Pile was by Alexander Mitchell in 1836 for Moorings and was then applied by Mitchell to M li Sands Maplin S d Li Lighthouse hh iin E England l d iin 1838 1838.

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In 1843, the 1st Screw Pile Light House in the U.S. was Constructed by Capt. William H. Swift at Black Rock Harbor in Connecticut. Swift used Mitchell Screw Pile Technology.

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In the 1840’s and ’50’s, More Than 100 Screw Pile Foundation Light Houses were Constructed Along the East Coast,, the Florida Coast and the Gulf of Mexico History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS Mitchell’s Screw Pile - 1836

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

PRODUCT TYPES

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Square Shaft Helical Screw Foundations & Anchors

A.B. Chance Type “SS” Characteristics

5500 - 20,000 ft lbs. Installation Torque

Design Tension Loads up to 100 kip (445 kN), g Comp. p Loads up p to 100 kip p ((445 kN)) Design Helix Dia: 6” (152 mm) 8” (203 mm) 10” (254 mm) 12” (305 mm) 14” (356 mm)

Type SS5 & SS150 1-1/2” (35 kips) SS175 1-3/4” (50 kips) SS200 22” (75 kips) SS225 2-1/4” (100 kips)

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

SCREW ANCHOR LEAD SECTION

Single, Twin, Triple or Quad Helix Configurations

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

PLAIN EXTENSION SECTION

3’-0 (.9 m), 5’-0 (1.5 m), 77’-00 (2 (2.11 m) & 10’-0 (3 m) Lengths

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

EXTENSION SECTION WITH HELIX PLATES 12” ((305mm)) and 14” (356 ( mm)) Diameter Helix Plates

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS F Foundation d ti Underpinning U d i i Brackets B k t STANDARD-DUTY FOUNDATION REPAIR BRACKET

FOR 1 ½” SHAFT RATED CAPACITIES: 20,000 LB. WITH SS5 ANCHORS 25,000LB. WITH SS150 ANCHORS FOR 1 ¾ ¾” RATED CAPACITY: 30,000LB.

HEAVY-DUTY FOUNDATION REPAIR BRACKET

FOR 1 ¾” SHAFT RATED CAPACITY: 40,000LB.

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Pipe Shaft Helical Screw Foundations A.B. Chance Type “LIFT & 278 C Combo” b ”

Characteristics

5 500 ft lbs.

5,500 lbs Installation Torque To q e Rating

Design Tension Loads up to 30 kip (133 kN), Design Comp. Loads up to 34 kip (133 kN) Helix Dia LIFT: 10” (254 mm) Helix Dia SS5/150 Lead: 6” (152 mm) 8” (203 mm) 10” (254 mm) 12” 10 12 (305 mm) 14” 14 (356 mm) Pipe Shaft Dia: 2-7/8” (73 mm)

Type yp SS5 to 278 “Combo” Pile

LIFT™ Pile LIFT History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Pipe Shaft Helical Screw Foundations A.B. Chance Type yp “HS” Characteristics

11,000 ft lbs. Installation Torque

Design Tension Loads up to 60 kip (267 kN), Design i C Comp. Loads d up to 60 ki kip (26 (267 k kN)) Helix Dia: 6” (152 mm) 8” (203 mm) 10” (254 mm) 12” (305 mm) 14 12 14” (356 mm) Pipe Shaft Dia: 3-1/2” (89 mm)

Type SS to HS “Combo” Pile

Type HS History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

APPLICATIONS FOR HELICAL SCREW ANCHORS 

Underpinning - Residential / Commercial

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Helical Screw Foundations for New Construction

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Tiebacks for Excavation Bracing

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Soil Nails for Earth Retention

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Seismic Retro-fit

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Guyy Anchors & Foundations for Towers History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Foundation Underpinning

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Foundation Underpinning Screw Foundation Installation with Portable Installer

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Foundation Underpinning Raising Building with Repair Brackets

Repair i Brackets k

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Helical Screw Foundations for New Construction

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

New Construction - Slabs and Foundations Screw Foundations Supporting I d t i l Building Industrial B ildi

Screw Foundations Supporting Structural Slab

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

PIPE SHAFT PILES

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

New C N Construction t ti – Connection Details

Pile Cap Detail

Grade Beam Connection Detail

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Helical Screw Foundations for Towers Installation of Screw Foundations with Back-Hoe

Ten Screw Foundations per Tower Leg

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Walkways for Wetlands

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Screw Anchor Tiebacks

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Soil Screws for Soil Nail Walls

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Guy Anchors for Towers Installation of Multiple Screw Anchors for Guy Point

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Guy Anchors for Towers

Single Guy Anchor, Multiple Guy Wires

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

THEORY AND DESIGN OF HELICAL PIER FOUNDATIONS

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Lateral Load Capacity

Grade Beam & Pile Cap

Passive Earth Pressure Resistance Optional Lateral Tieback

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Tieback Screw Anchor Section Detail

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Soil Screw Anchor Section Detail

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

HeliCAPTM Engineering Software Theoretical Bearing Capacity Based on Soil Strength

Available from A. B. Chance Civil Construction Web Site www.abchance.com

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

INSTALLATION TORQUE VS. ULTIMATE CAPACITY

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS TORQUE MOTOR

REACTION BAR

FOOT CONTROL 2,500ft-lbs through 8,000ft-lbs

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS Hydraulic Vehicle-Mounted Hydraulic, Vehicle Mounted

3,500 , FT.-LB. 6,000 FT.-LB. 12,000 FT.-LB. 20 000 FT 20,000 FT.-LB -LB History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS MACHINE

TORQUE MOTOR

CROWD

TORQUE INDICATOR FOUR HELIX LEAD SECTION

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

FIELD MODIFICATIONS  Vary

Helix Size

 Vary

Helix Numbers

 Install

into Better Soil

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Compression Load Test Set Set-Up Up

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

HELICAL PULLDOWN® MICROPILES 

Screw Pile Foundation Installation Method Used to Increase the Section Modulus of a Standard SS or Pipe Shaft.

Shaft

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Patent Protected  

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U.S. 5,707,180; Methods and Apparatus Other U.S. and Foreign Patents Pending

Method of Displacing Soil Around the Anchor Shaft and Replacing with Grout Column Column.  

Soil is Displaced by “Lead Displacement Plate”.

“Extension Displacement Plates” Serve as Centralizers and Provide the Means for Which the Grout is “Pulled-Down”.

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

DESCRIPTION 

Increased Section Modulus Likewise Increases Lateral Buckling Capacity of the Screw Pile.

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Grout Column Provides Increased Compression C Capacity. it 

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Mobilizes Skin Friction at the Grout/Soil Interface.

Displacement Plates Range in Size from 4” 4 Up to 10” in Diameter.  

Required Plate Size is Specified for Each Project G tC Grout Columns l Can C bbe Cased C d when h R Required. i d

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Helical Screw Foundations With Grouted Shafts

HELICAL PULLDOWN Micropile Characteristics

5500 - 20,000 ft lbs. Installation Torque

Design Tension Loads up to 100 kip (445 kN), g Comp. p Loads up p to 200 kip p ((890 kN)) Design Helix Dia: 6” (152 mm) 8” (203 mm) 10” (254 mm) 12” (305 mm) 14” (356 mm)

Prevents Buckling Increases Capacity C Corrosion i Resistance R i

Uses Type SS (Square Shaft) Material

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

HELICAL PULLDOWNTM Micropile MODEL Qt = QH + Qf

Grade

Soft or Loose Overlying Strata Displacement Plates

Qf = Df  sLf]

Grout Column Helix Plates

E dB End Bearing i Stratum St t

QH = icCi  qiNq History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Installingg Lead Case

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS Pouring Grout

Joint Packingg History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS Installing Top Case

Adding Centralizer History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS Installing Shaft Extension

Grout “Pulled Down” History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Pile Extracted After Test Un-Cased Grout Column

T Case Top C

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

Grout Column With Soil Removed

History, Applications, Design

HELICAL ANCHORS & FOUNDATIONS

History, Applications, Design