Stelcor® DDM

Cleaner Faster Better Micropiles

STELCOR uses the elements of a traditional micropile and gets them in the ground cleaner and faster. The STELCOR pile takes advantage of the strengths of steel and grout, uses relatively small installation equipment, produces no spoils, and consistently produces better results than were projected in design.

With STELCOR, the soil is displaced and not removed. The result is greater loads at lesser depths. The STELCOR pile is embedded into the improved soil with a unique corrugated weave of grout which greatly enhances the soil bond and load transfer capacity. From structural, geotechnical, mechanical, and installation standpoints, STELCOR just makes sense, and the load test results prove it.

One of the many benefits of STELCOR DDM is that it can be used in situations where similar deep foundations would not have been feasible due to costly spoils removal, time constraints, limited access, and other factors. STELCOR DDMs are installed using minimal installation equipment – this can result in significant savings on mob/demob costs compared to similar pile types. STELCOR really excels in challenging environments where tight access and high-water tables are present. Another benefit of STELCOR DDM is that no spoils are created during installation. This is especially beneficial on sites where contamination is present and/or where spoils removal is costly.

For quality assurance purposes, STELCOR DDMs are only installed by IDEAL Certified Installers. For more information Contact Us and we will be happy to answer any questions you may have.

TECHNICAL EXPLANATION

STELCOR Drilled-In Displacement Micropiles are installed using hydraulic powered rotary equipment and are turned into the ground while crowd or downward pressure is exerted on the steel core and a continuous flow of grout is provided to the top of the pile. Reverse grout flow flighting welded to the steel core draws the grout into the annulus created by a displacement head located near the tip of the steel core.

The welded reverse flighting ensures a continuous grout column and structural load transfer from the grout column into the 55 to 80 ksi steel core.

Grout ports in the steel core also provide consistent grout placement along the length of the pile.

No soil is removed during installation of STELCOR Drilled-In Displacement Micropiles and a new steel core is installed and left in the ground for every pile.

The STELCOR displacement lead section includes a helicoidal driving plate, a lateral displacement plate, and a secondary deformation structure.

The driving plate helps advance the pile downward and provides end bearing support.

The lateral displacement plate creates a positive annulus around the steel core by displacing the soil outward, enhancing the density surrounding the pile element.

The secondary deformation structure produces a ribbed or corrugation effect along the grouted pile shaft, greatly enhancing soil bond and load transfer.

A continuous grout column is there by created by means of the STELCOR displacement lead section and reverse grout flow flighting. The steel structural core extends the entire length of the pile ensuring unbroken structural integrity.

ONE OR MORE OF THE FOLLOWING PATENTS MAY APPLY:
US 8,926,228 B2 & US 10,480,144 B2; OTHER PATENTS PENDING.

ADVANTAGES

Vibrationless Installation

STELCOR DDMs are installed with almost zero vibration. This is why they’re a preferred deep foundation when deep foundations are required near schools, hospitals, historical buildings, or any structure with an already compromised foundation.

High Water Table Installation

Grout is heavier than water, so even if there is groundwater present, the grout flows continuously and fills the voids created by the pile installation.

Minimal Mobilization and Demobilization Costs

Hauling equipment to and from a site is costly and time-consuming, especially in metropolitan areas.  Depending on the project, this may have to be done several times over the course of the pile installation. The only equipment needed for installing STELCOR DDMs is an excavator or skid-steer, a hydraulic-powered rotary drive head, and a high sheer colloidal grout mixer. With no specialty cumbersome installation equipment setup, on-site mobilization and demobilization is a cakewalk.

No Soil Removal

As the pile is installed, the lateral displacement plate on the tip of the STELCOR DDM pile displaces the soil. Not only does this eliminate the cost of removing spoils (even more costly when contaminated), it also enhances the density of the soils surrounding the pile.

Additional Benefits:

  • Exceptional lateral capacity
  • No reduction in bending capacity at the bolted connection
    (unlike threaded connections)
  • Predictable grout volumes and placement
  • Positive grout displacement
  • Lower cost per kip of support compared to most other pile types
  • Can be installed in tight access and low overhead environments

What is the Cost of Pile Per Foot?

When considering material cost with STELCOR DDMs, it’s important to consider all the factors in order to know your true cost per foot of piling. As one developer so perfectly put it, “I want to know my cost-per-kip of support with each piling option, not my cost per foot of material.” Below are a few points to help you drill down and understand the true cost per foot of STELCOR DDM’s vs other piling options.

Materials

Depending on the soil type, a STELCOR DDM pile will often achieve the same or higher capacity as other pile types while being installed to lesser depths.

Equipment

To install STELCOR DDMs, you need a high shear colloidal grout mixer, a hydraulic rotary drive head, and an excavator or mini-skid (one or both of which are often already on site). What installation equipment is needed to install other pile types and what is the cost of getting that equipment on site?

Time

If a pile can be installed to a lesser depth while achieving the same capacity, this will save even more time and money.  How quickly can a STELCOR DDM pile be installed vs. other piling options? A 60′ STELCOR DDM pile can easily be installed in 30 minutes.  That included placing the initial 20′ lead section, installing it, adding two more 20′ extensions and installing them, and then moving to the next pile location. 

Our design team provides preliminary design options to give our clients the lowest cost per kip of support, and it costs the client nothing. Click here to send your project info to the IDEAL Design Team.

INSTALLATION SEQUENCE AND GROUT TAKE ESTIMATION FOR STELCOR

 

PART 1. GENERAL DESCRIPTION

DDM’s are installed using hydraulic powered rotary equipment and are turned into the ground while crowd or downward pressure is exerted on the steel core and a continuous flow of grout is provided to the top of the pile. A reverse flighting welded to the steel shaft draws the grout into the annulus created by a displacement head located near the tip of the steel core.

PART 2. INSTALLATION SEQUENCE

1. Attach the hydraulic drive head to the DDM lead section and align pile tip at specified pile location.
2. Advance the lead section 12 inches below ground and lift up, removing soil, to create a grout reservoir. Remove soil from extracted pile tip, fill the reservoir with grout, and re-insert lead section.
3. As the lead section advances beyond the grout reservoir, commence grout flow. Monitor and record grout take during entire installation of each pile using the STELCOR pile installation record provided. A grout flow meter can be utilized to increase grout volume measurement accuracy.
4. Grout shall flow continuously to fill the annulus created by the DDM displacement head. Maintain grout level within 24 inches of installation grade.
5. Sufficient crowd shall be applied to the pile throughout the entire installation process to ensure 6 inches of advancement per revolution.
6. Where extensions are required, stop the drive head and remove from lead section.
7. Attach the hydraulic drive head to a DDM extension section.
8. Attach the extension section to the lead section with specified hardware and continue installation. Add extensions as required to reach design depth.
9. If dense soils or obstructions are encountered and the pile will not advance, reverse the pile 24 inches and re-advance. Repeat 3 to 5 times while measuring how much the pile advances each time. Do not exceed maximum specified torque of the shaft. If the pile will not advance, then pre-auguring may be required to reach design depth. Consult with Ideal to determine if the pile can be terminated in dense/stiff layers above design depth.
10. If the pile top is terminated above the pile cut-off elevation, cut the steel core using an appropriate method such as a band saw or torch.
11. Upon completion of pile installation, ensure that the grout level is brought to the top of pile (inside and outside of the steel core).
12. Install steel pile cap if applicable.
13. Document installation torque every 5 feet during installation and at pile termination using the STELCOR pile installation record provided. Pile capacity is not determined by installation torque and data is used as reference only.

PART 3. GROUT TAKE APPROXIMATIONS

Recommended grout mix of 0.44 water to cement (W/C) or 94 lb. bag to 5 gallons of water using Type I/II Portland cement. A colloidal mixer must be used.

• STELCOR 1200 – 0.38 Cubic ft. per lineal foot (0.33 bags per lineal foot)
• STELCOR 1400 – 0.44 Cubic ft. per lineal foot (0.38 bags per lineal foot)
• STELCOR 1600 – 0.67 Cubic ft. per lineal foot (0.59 bags per lineal foot)
• STELCOR 1800 – 0.88 Cubic ft. per lineal foot (0.77 bags per lineal foot)
• STELCOR 2000 – 1.15 Cubic ft. per lineal foot (1.00 bags per lineal foot)

Note: Published grout take approximations are for bidding purposes only. Actual grout take will vary depending on soil type. The test pile(s) establishes the installation parameters including depth, grout take, and capacity for production piles in the site-specific soil.

Blair Street

Location Blair Street
City Milford
State CT
Design Load 12 Ton
Pile Detail SC1200
Shaft Diameter 2.875″
Depth 27
Drive Plate 14″

Farmington Canal

Location Farmington Canal
City Farmington
State CT
Design Load 15 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 28
Drive Plate 14″

Milford

Location Milford
City Milford
State CT
Design Load 17.5 Ton
Pile Detail SC1200
Shaft Diameter 2.875″
Depth 42
Drive Plate 14″

DC Water & Sewer

Location DC Water & Sewer
City Washington
State DC
Design Load 51 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 62
Drive Plate 14″

EvaClaire

Location EvaClaire
City Willis
State FL
Design Load 15 Ton
Pile Detail SC1600
Shaft Diameter 3.5″
Depth 12
Drive Plate 18″

Wesley Chapel

Location Wesley Chapel
City Tampa Bay
State FL
Design Load 20 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 20
Drive Plate 18″

Harris Residence

Location Harris Residence
City West Palm Beach
State FL
Design Load 25 Ton
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 20
Drive Plate 14″

Lakeland Medical Center

Location Lakeland Medical Center
City Lakeland
State FL
Design Load 30 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 20
Drive Plate 18″

West Palm Beach

Location West Palm Beach
City West Palm Beach
State FL
Design Load 30 Ton
Pile Detail SC1000
Shaft Diameter 3.5″
Depth 55
Drive Plate 12″

Marina Expansion

Location Marina Expansion
City Riviera Beach
State FL
Design Load 35 Ton
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 10
Drive Plate 14″

Tarpon Springs, FL

Location Tarpon Springs, FL
City Tarpon Springs
State FL
Pile Detail SC1200
Shaft Diameter 2.875″
Depth 33
Drive Plate 14″

Atlanta, GA

Location Atlanta, GA
City Atlanta
State GA
Design Load 30 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 23
Drive Plate 14″

Northtown Storage

Location Northtown Storage
City Chicago
State IL
Design Load 43 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 45
Drive Plate 18″

Northtown

Location Northtown
City Chicago
State IL
Design Load 43 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 60
Drive Plate 18″

Natchitoches

Location Natchitoches
City Natchitoches
State LA
Design Load 15 Ton
Pile Detail SC1000
Shaft Diameter 2.875″
Depth 20
Drive Plate 12″

Vertical Turret Lathe Addition

Location Vertical Turret Lathe Addition
City Shreveport
State LA
Pile Detail SC

Moulton Street

Location Moulton Street
City Cambridge
State MA
Design Load 20 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 33
Drive Plate 14″

Beacon Street

Location Beacon Street
City Boston
State MA
Design Load 25 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 20
Drive Plate 14″

Boston Design Center

Location Boston Design Center
City Boston
State MA
Pile Detail SC1100
Shaft Diameter 3.5″

Rutgers University

Location Rutgers University
City Newark
State NJ
Design Load 100 & 125 Ton
Pile Detail SC1600
Shaft Diameter 5.5″ & 7″
Depth 35
Drive Plate 18″

Lake Avenue

Location Lake Avenue
City Cape May County
State NJ
Design Load 20 Ton
Pile Detail SC1200
Shaft Diameter 2.875″
Depth 40
Drive Plate 14″

NBCUA

Location NBCUA
City Waldwick
State NJ
Design Load 20 Ton
Pile Detail SC1000
Shaft Diameter 3.5″
Depth 30
Drive Plate 12″

GSU Transformer

Location GSU Transformer
City Jersey City
State NJ
Design Load 30 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 47
Drive Plate 14″

Lowes of Union

Location Lowes of Union
City Union
State NJ
Pile Detail SC1600
Shaft Diameter 7″

Brunswick St

Location Brunswick St
City Jersey City
State NJ
Pile Detail SC1100
Shaft Diameter 3.5″

Bayway I-95 Crossing

Location Bayway I-95 Crossing
City Bayway
State NJ
Pile Detail SC1600
Shaft Diameter 7″ 5.5″

Substation

Location Substation
City Passaic Valley
State NJ
Pile Detail SC1200
Shaft Diameter 2.875″
Depth 45
Drive Plate 16″

Woodhaven Blvd

Location Woodhaven Blvd
City Queens
State NY
Design Load 10 Ton
Pile Detail SC1000
Shaft Diameter 2.875″
Depth 20
Drive Plate 12″

Walton Ave

Location Walton Ave
City Bronx
State NY
Design Load 100 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 40
Drive Plate 16″

DHL Warehouse - JFK Airport

Location DHL Warehouse – JFK Airport
City Queens
State NY
Design Load 100.5 Ton
Pile Detail SC1600
Shaft Diameter 7″
Depth 66
Drive Plate 18″

Beach Ave Pump Station

Location Beach Ave Pump Station
City Northport
State NY
Design Load 15 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 40
Drive Plate 14″

211 McGuiness Blvd

Location 211 McGuiness Blvd
City Brooklyn
State NY
Design Load 150 Ton
Pile Detail SC1600
Shaft Diameter 7″
Depth 40
Drive Plate 18″

Wolcott St

Location Wolcott St
City Brooklyn
State NY
Design Load 20 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 30
Drive Plate 14″

Second Ave

Location Second Ave
City New York
State NY
Design Load 20 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 35
Drive Plate 14″

East 147th

Location East 147th
City Bronx
State NY
Design Load 20 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 27
Drive Plate 14″

MTA 207th Street Yard

Location MTA 207th Street Yard
City New York
State NY
Design Load 22 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 40
Drive Plate 18″

Flushing Tunnel

Location Flushing Tunnel
City Flushing
State NY
Design Load 22 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 26
Drive Plate 14

New York Ave

Location New York Ave
City Long Beach
State NY
Design Load 23 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 20
Drive Plate 18″

Aldi Supermarket

Location Aldi Supermarket
City Rome
State NY
Design Load 25 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 30
Drive Plate 14″

First Avenue

Location First Avenue
City Manhattan
State NY
Design Load 25 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 40
Drive Plate 16″

Aldi Supermarket

Location Aldi Supermarket
City Utica
State NY
Design Load 25 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 30
Drive Plate 14″

Stewart Avenue

Location Stewart Avenue
City Brooklyn
State NY
Design Load 27 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 30
Drive Plate 14″

Spielvogel Residence

Location Spielvogel Residence
City Larchmont
State NY
Design Load 28 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 28
Drive Plate 14

Paris Hotel

Location Paris Hotel
City Queens
State NY
Design Load 30 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 30
Drive Plate 14″

Fresh Creek Sewers

Location Fresh Creek Sewers
City Brooklyn
State NY
Design Load 30 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 25
Drive Plate 14″

Sackett Street

Location Sackett Street
City Brooklyn
State NY
Design Load 30 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 30
Drive Plate 14″

JFK Airport

Location JFK Airport
City Queens
State NY
Design Load 30 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 25
Drive Plate 18″

JFK Airport Fuel Lines

Location JFK Airport Fuel Lines
City Queens
State NY
Design Load 32.5 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 25
Drive Plate 18″

JFK Airport – Foam Support

Location JFK Airport – Foam Support
City Queens
State NY
Design Load 32.5 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 25
Drive Plate 18″

JFK Airport – Buckeye Refinery

Location JFK Airport – Buckeye Refinery
City Queens
State NY
Design Load 32.5 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 25
Drive Plate 18″

Finger Lakes Welcome Center

Location Finger Lakes Welcome Center
City Geneva
State NY
Design Load 36 Ton
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 10
Drive Plate 14″

Stillwell Ave

Location Stillwell Ave
City Brooklyn
State NY
Design Load 37.5 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 40
Drive Plate 18″

63 Columbia St

Location 63 Columbia St
City Brooklyn
State NY
Design Load 40 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 62
Drive Plate 14″

West Houston St

Location West Houston St
City Manhattan
State NY
Design Load 40 Ton
Pile Detail SC1200
Shaft Diameter 3.5″
Depth 40
Drive Plate 14″

MTA 207th Street Yard

Location MTA 207th Street Yard
City New York
State NY
Design Load 41.5 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 60
Drive Plate 18″

West 127th St

Location West 127th St
City Manhattan
State NY
Design Load 50 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 50
Drive Plate 14″

23rd Street

Location 23rd Street
City Astoria
State NY
Design Load 50 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 20
Drive Plate 14″

26th Ward WWTP

Location 26th Ward WWTP
City Brooklyn
State NY
Design Load 55 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 30
Drive Plate 16″

Brooklyn WWTP

Location Brooklyn WWTP
City Brooklyn
State NY
Design Load 55 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 45
Drive Plate 16″

Ainslie Street

Location Ainslie Street
City Brooklyn
State NY
Design Load 60 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 35
Drive Plate 14″

86 Delancey St

Location 86 Delancey St
City New York
State NY
Design Load 60 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 30
Drive Plate 18″

Mermaid Ave

Location Mermaid Ave
City Brooklyn
State NY
Design Load 60 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 35
Drive Plate 14″

Coney Island, NY

Location Coney Island, NY
City Coney Island
State NY
Design Load 60 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 30
Drive Plate 14″

Bay Street

Location Bay Street
City Staten Island
State NY
Design Load 60 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 25
Drive Plate 18″

Parker Street

Location Parker Street
City Fairport
State NY
Design Load 60 Ton
Pile Detail SC1400
Shaft Diameter 7″
Depth 10
Drive Plate 16″

West 15th St

Location West 15th St
City Brooklyn
State NY
Design Load 75 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 50
Drive Plate 18″

College Point

Location College Point
City Queens
State NY
Design Load 75 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 40
Drive Plate 18″

King Street

Location King Street
City Bronx
State NY
Design Load 80 Ton
Pile Detail SC1600
Shaft Diameter 7″
Depth 36
Drive Plate 20″

The Gilbert Building

Location The Gilbert Building
City Manhattan
State NY
Design Load 85 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 65
Drive Plate 16″

Draper Hall

Location Draper Hall
City Manhattan
State NY
Design Load 85 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 70
Drive Plate 16″

74 Grand St

Location 74 Grand St
City Manhattan
State NY
Design Load 90 Ton
Pile Detail SC1600
Shaft Diameter 5.5″
Depth 56
Drive Plate 18″

Lonza Facility Building

Location Lonza Facility Building
City Rochester
State NY
Pile Detail SC1100
Shaft Diameter 3.5″

Commack Public Library

Location Commack Public Library
City Commack
State NY
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 22
Drive Plate 14″

Syracuse, NY

Location Syracuse, NY
City Syracuse
State NY
Pile Detail SC800
Shaft Diameter 2.875″
Depth 20
Drive Plate 12″

Alfred State University

Location Alfred State University
City Alfred
State NY
Pile Detail SC1000
Shaft Diameter 3.5″
Depth 17
Drive Plate 12″

Fassett Elementary

Location Fassett Elementary
City Elmira
State NY
Pile Detail SC1000
Shaft Diameter 3.5″
Depth 42
Drive Plate 12″

Mercy High School

Location Mercy High School
City Brighton
State NY
Pile Detail SC1000
Shaft Diameter 3.5″
Depth 10
Drive Plate 12″

51 Ransier Drive

Location 51 Ransier Drive
City West Seneca
State NY
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 30
Drive Plate 16″

Cuyahoga Valley

Location Cuyahoga Valley
City Cuyahoga Valley
State OH
Design Load 57.5 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 55
Drive Plate 14″

26th Ave

Location 26th Ave
City Portland
State OR
Design Load 31 Ton
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 95
Drive Plate 14″

Sewer Departmet

Location Sewer Departmet
City North Bethany
State OR
Design Load 40 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 40
Drive Plate 18″

Traffic Signals

Location Traffic Signals
City North Bend
State OR
Pile Detail SC1600
Shaft Diameter 7″
Depth 35
Drive Plate 18″

Aldi Supermarket

Location Aldi Supermarket
City Kingston
State PA
Design Load 20 Ton
Pile Detail SC1100
Shaft Diameter 3.5″
Depth 40
Drive Plate 14″

Sunoco Refinery

Location Sunoco Refinery
City Marcus Hook
State PA
Design Load 37.5 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 25
Drive Plate 16″

Point Street

Location Point Street
City Providence
State RI
Design Load 28 Ton
Pile Detail SC1200
Shaft Diameter 5.5″
Depth 73
Drive Plate 14″

Vermont Castings

Location Vermont Castings
City Randolph
State VT

Petrogas

Location Petrogas
City Ferndal
State WA
Design Load 30 Ton
Pile Detail SC1400
Shaft Diameter 5.5″
Depth 20
Drive Plate 18″