Supportworks 6WeS Concentric Push Pier
Specifications:
- Product Name: Concentric Push Pier Installation
- Depth: 40 inches below the bottom of the footing
- System Type: Hydraulically Driven Push Pier
Product Usage Instructions:
Preparation:
Ensure all necessary tools and components are available before starting the installation process.
Installation Steps:
Step 1: Preparing Bottom of Footing
- Excavate soil beneath the footing to the required depth.
- Remove any soil adhered to the bottom of the footing.
- Use a chipping hammer as necessary to create a flat and level surface.
Step 2: Setting Up Drive Stand
- Place collapsed drive stand under the footing, centering it below the foundation wall.
- Level and plumb the drive stand.
- Raise the top of the drive stand to be close to the bottom of the footing.
- Insert hitch pins into the upper holes on the drive stand legs.
Step 3: Installing Hydraulic Drive Cylinder
- Place a starter tube section on top of the floating middle plate.
- Connect hydraulic pump to the cylinder.
- Slowly extend the cylinder until it engages the bottom of the footing.
Step 4: Advancing Push Pier Tube
- Ensure starter section is plumb and adjust the drive stand if necessary.
- Begin advancing push pier tubes starting from small to large sizes.
- Check alignment periodically and tighten coil nuts as needed.
Cleaning Up:
After completing the installation, remove all equipment and debris from the site.
FAQ:
Q: How do I know when to stop advancing the push pier
tube?
A: Pier advancement should be terminated when the target drive pressure is achieved, or if the structure starts to mobilize.
Q: What should I do if the drive stand is not level?
A: Adjust the drive stand to ensure it is level and plumb before proceeding with the installation process.
Concentric Push Pier Installation
The concentric push pier system is used to stabilize and lift settled foundations. Unlike the typical “sideload” retrofit brackets, these systems are installed directly beneath foundation walls or point loads and, therefore, are not exposed to bending forces generated from off-set, eccentric loading conditions (Figure 2.46). Concentric piers are commonly used in FRQQHG VSDFHV VXFK DV FUDZO VSDFHV RU WXQQHOV RQ pier-and-beam foundations, on post-tensioned slab interior grade beams, and under shallow exterior wall footings with limited soil cover.
Figure 2.46 Concentric pier installation
Figure 2.47 Prepare bottom of footing with chipping hammer, as necessary, to create a flat and level surface
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Chapter 2 Hydraulically Driven Push Pier Systems
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Place collapsed drive stand under the footing and center below the foundation wall above.
Level and plumb the drive stand.
Remove hitch pins from the telescoping legs.
Raise the top of the drive stand to as close to the bottom of footing as possible.
Insert hitch pins into the upper holes on the drive stand legs. If installing a grout plate, place plate with grout on top of drive stand (Figure 2.48).
Place a starter tube section on top of the floating middle plate.
5DLVHWKHRDWLQJPLGGOHSODWHXQWLOWKHWRSSODWHRQWKH drive stand is approximately two inches below the bottom of the footing (Figure 2.49).
Tighten the coil nuts on both sides of the drive stand.
Remove starter tube from the middle plate.
Place hydraulic drive cylinder on the middle plate (Figure 2.50).
Place starter section and small drive tube through the hole in the drive stand bottom plate.
Connect hydraulic pump to the cylinder.
Slowly extend cylinder until the top of the drive stand engages the bottom of footing (Figure 2.51).
Tighten the coil nuts on both sides of the drive stand.
Figure 2.48 Grout plate used to create uniform bearing
Figure 2.49 Drive stand setup within excavation
Figure 2.50 Placement of hydraulic drive cylinder
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Figure 2.51 Extend hydraulic cylinder to engage footing
Chapter 2 Hydraulically Driven Push Pier Systems
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Make sure starter section is plumb and adjust drive stand as necessary (Figure 2.52).
Fully extend cylinder.
Fully retract cylinder.
Remove small drive tube.
Place medium drive tube onto starter tube.
Fully extend cylinder.
Fully retract cylinder.
Remove medium drive tube.
Place large drive tube onto starter tube.
Fully extend cylinder. 5HFRUGQDOGULYHSUHVVXUHIRUWKDWVHFWLRQ
Figure 2.52 Check alignment of drive stand and starter section
Fully retract cylinder.
Remove large drive tube.
Place an 18-inch long push pier tube into the starter section.
Repeat procedure for rest of the tube sections. Pier advancement is terminated when the target drive pressure is achieved, or the structure starts to mobilize.
Occasionally check that the coil nuts are tight and that the drive stand and pier sections are plumb.
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Extend cylinder and loosen coil nuts several inches.
Fully retract cylinder and remove from drive stand.
Remove hitch pins and lower drive stand to the collapsed position.
Place hitch pins into the lower holes on the drive stand legs.
Remove drive stand assembly from excavation.
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Chapter 2 Hydraulically Driven Push Pier Systems
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Measure the distance from the bottom of the footing to the top of the last pier tube (Figure 2.53).
Subtract 15 inches from the measured dimension and cut a 36-inch long pier tube to this lenght.
Connect the pier cap to the bracket with coil rods and nuts.
Insert the cut pier tube through the bottom plate of the bracket and up against the pier cap.
Secure the pier tube to the bracket with the Concentric Pier Vice Grip (Figure 2.54).
Place bracket assembly onto the last driven pier tube (Figure 2.55).
Remove the vice grip.
Lift bracket to the bottom of the footing.
Tighten the coil nuts.
Place hydraulic cylinder on top of the pier cap.
Slowly extend the cylinder until the top of the bracket is snug against the bottom of footing (Figure 2.56).
Make sure the bracket is plumb and adjust as necessary.
Tighten coil rod nuts.
Figure 2.53 Measure from bottom of footing to top of installed pier section
Figure 2.54 Assemble bracket and pier section outside of excavation
Figure 2.55 Place bracket assembly onto last driven pier tube
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Figure 2.56 Place hydraulic cylinder and snug bracket against footing
Chapter 2 Hydraulically Driven Push Pier Systems
6WeS 6 6WruFWurDO /iIW DQGRr /RFN 2II Refer to Section 2.96WHSIRUQDOSURFHGXUHV
6WeS 7 %DFNOO &OeDQ 8S Completely backfill all excavations and properly compact soil with a mechanical tamper.
Figure 2.57 Completed concentric pier installation
Concentric Piers with SmartJacks
Concentric piers can also be used as supplemental support beneath main girders in crawlspaces in order to provide a deep foundation for the SmartJack system (See Chapter 4). The concentric piers will transfer the load from the girders through weak upper soils and into competent load bearing strata below (Figure 2.58). Refer to the WHFKQLFDOVSHFLFDWLRQVZLWKLQAppendix 2 (for concentric piers) and Appendix 4 (for SmartJacks) for component and system capacities.
© 2021 Supportworks® All Rights Reserved
Figure 2.58 Graphic of concentric pier/SmartJack installation. Backfill around EDVHRI6PDUW-DFNQRWVKRZQIRUFODULW%DFNILOOLVUHTXLUHG
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Chapter 2 Hydraulically Driven Push Pier Systems
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([FDYDWH DQ DSSUR[LPDWH IRRW VTXDUH KROH to a distance of 40 inches below the bottom of the girder.
Bottom of excavation should be flat and level.
Backfill and compact thoroughly to the top of the base plate (Figure 2.61)
See Steps 2, 3, and 4 within the Concentric Push Pier Installation (Figure 2.59).
The top of the last installed pier tube should be below the ground surface elevation, i.e., below the top of the excavation. Cut tube as necessary.
6WeS 2 3 3ier ,QVWDOODWiRQ See Steps 2, 3, and 4 within the Concentric Push Pier Installation (Figure 2.59). The top of the last installed pier tube should be below the ground surface elevation. Cut tube as necessary.
Figure 2.61
Complete Steps 3 through 5 from Section 4.2. 6WeS 4 %DFNOO &OeDQuS
Figure 2.59 Concentric pier drive stand beneath main girder in crawl space
Backfill and compact soil to fil the remainder of the excavation. Level out extra spoils, replace FRQFUHWH RU LQVWDOO D FUDZO VSDFH OLQHU DV UHTXLUHG
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Place the SmartJack/Concentric Pier Base Plate onto the last installed pier tube (Figure 2.60).
© 2021 Supportworks® All Rights Reserved
Figure 2.60
231
Figure 2.62 Completed concentric pier/SmartJack installation. Model 288 SmartJack shown.
Chapter 2 Hydraulically Driven Push Pier Systems
Preliminary Design Services
Preliminary design services and consultation for prospective piering, anchoring and slab stabilization projects
are provided at no cost to design professionals and installing contractors. These services may include review of
available site and soil information, review of plans and specifications, and development of preliminary design
recommendations with Supportworks products given the load and deflection criteria specified. For example, if
a potential helical pile project is submitted, Supportworks engineers may provide recommendations for shaft
size, helix plate configuration, target installation torque, and depth. Other recommendations may include sizing
of drive heads and installation equipment, use and type of calibrated torque monitoring equipment, selection
of new construction or retrofit brackets, and how to deal with conditions that may affect installation. If the site
or project is not a good fit for helical piles, or any of the other products offered by Supportworks, that opinion
would be provided also.
A request for preliminary design services can be submitted online at OnStableGround.com or by contacting the
Supportworks Engineering Department at 402-885-6615 or engineering@supportworks.com.
HelixPro® Helical Foundation Design Software
To simplify the design process for helical piles and tiebacks, Supportworks created HelixPro® Helical Foundation Design
Software for Professionals, a web-based helical foundation design tool available free of charge to design professionals.
With the software being web-based, minor updates and revisions are automatic. You never have to worry about having
the most recent version. The program calculates compression and uplift capacities of Supportworks helical piles,
tension capacities of Supportworks helical tiebacks, and compression and uplift capacities of Helicast™ piles, i.e., piles
designed and constructed with a grout column surrounding the helical pile extension sections. HelixPro calculates
pile and tieback end-bearing capacities using the Individual Bearing Method. For calculation of frictional resistance
of Helicast piles, the user can select from three common methods and also utilize “User Input Bond Values.” For more
information about the design of helical piles, Helicast piles and helical tiebacks, visit Chapter 1 of this Technical Manual.
Documents / Resources
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Supportworks 6WeS Concentric Push Pier Installation [pdf] Installation Guide 6WeS, 2 riYe, 6WDQG, GrDuOiF, OiQGer, 6WeS Concentric Push Pier Installation, 6WeS, Concentric Push Pier Installation, Push Pier Installation, Pier Installation, Installation |
