TECHNICAL DATASHEET

TAKE A LOOK AT OUR TECHNICAL SHEETS

No matter what the size or scope of your projects, we offer a wide selection of Thermal Screw Piles that will meet or exceed your expectations. For more information on our products, please select a pile from the following list.

POSTECH PILE P178 (1 7/8″)

PRODUCT CHARACTERISTICS
Physical and Chemical properties
STEEL GRADE Conform to CAN/CSA G40.21-350W and/or ASTM A500 class C
ARC WELDING Conform to CSA W59-13
HOT DIP GALVANIZATION Conform to ASTM-A123M
THERMAL INSULATION Unique polyurethane foam
Standard characteristics
TUBING DIAMETER 48 mm (1 7/8 in)
BLADE DIAMETER From 200 to 255 mm (8 and 10 in)
TUBING LENGTH Standard of 2.1 m and 3 m (7 pi and 10 pi)
TUBING THICKNESS 3.7 mm (0.145 in)
BLADE THICKNESS 8 mm (5/16 in) for diameters of 8 and 10 po
ADAPTER HEADS Various forms as needed according to the project specifications
EXTENSIONS Available according to project specifications
ALLOWABLE MECHANICAL RESISTANCE (SLS)
MAXIMUM COMPRESSIVE AND TENSILE OF TUBING 90 kN
BENDING MOMENT OF TUBING 1.5 kN.m
SLS = Service Limit State

DESIGN INFORMATION

BEARING CAPACITY

Postech products are designed to bear compressive, tension and lateral loads through the blade at the bottom of the shaft. The design of the shaft and the size of the blade depend on the load and on the bearing capacity of the soil. The monitoring of the applied torque on site allows for the confirmation of the allowable bearing capacity (SLS) of the soil.

THERMAL INSULATION

Postech products are insulated by a process of injecting polyurethane foam in the piles shaft. The revolutionary insulation system ensures that the inside of the pile is maintained at a temperature that will prevent ice or frost build-up at the base of the pile; providing optimal protection against ground motion using our planet’s heat.

SCREW PILE ADVANTAGES

  • Product and installation is supplied, you only need to mark the spot!
  • Can be installed in all climates, weather or ground conditions;
  • No excavation usually required, minimal impact to your property;
  • No waiting time, you can build as soon as the installation is ready;
  • Reusable and recyclable, environmentally friendly;
  • Can be installed under an existing structure;
  • The most reliable & economical solution available.

ALLOWABLE LOAD VALUES

The geotechnical calculations for Postech’s screw piles were carried out in accordance with the requirements of sub-section 4.2.4 of the National Building Code (NBC). We used the design methods set out in Chapters 19 and 20 of the Canadian Foundation Engineering Manual (CFEM). These calculations are based on the physical and mechanical properties of the on-site at the blade depth and along the steel tubing.

ALLOWABLE LOADS (SLS) – COHESIVE SOILS (CLAY)

Undrained shear strengths (kPa) Allowable bearing capacities of soils (kPa)* ALLOWABLE LOADS (kN)
Blade 200 mm Ø (8″ Ø) Blade 255 mm Ø (10″ Ø)
C=compressive, T=tensile C T C T
30 50 5 3 8 5
44 75 7 5 11 7
58 100 9 6 15 10
73 125 12 8 19 12
88 150 14 10 23 15
102 175 16 11 27 17
117 200 19 13 30 20
145 250 23 16 38 24
≥175 ≥300 28 20 46 29
* Note: For a conventional strip footing with a width of less than 1 m. SLS = Service Limit State

ALLOWABLE LOADS (SLS) – COHESIONLESS SOILS (SILT, SAND OR GRAVEL)

Indices de compacité N Allowable bearing capacities of soils (kPa)* ALLOWABLE LOADS (kN)
Blade 200 mm Ø (8″ Ø) Blade 255 mm Ø (10″ Ø)
C=compressive, T=tensile C T C T
3 50 4 3 6 4
5 75 6 4 10 7
6 100 7 5 12 9
8 125 10 7 16 11
10 150 12 9 20 14
11 175 13 10 21 16
13 200 16 11 25 19
16 250 19 14 31 23
20 300 24 18 39 29
≥25 ≥ 350 30 22 49 36
* Note: For a conventional strip footing with a width of less than 1 m. SLS = Service Limit State

COHESIONLESS SOILS (SILT, SAND OR GRAVEL)

ALLOWABLE LOADS (SLS) DEPENDING ON APPLIED TORQUES

APPLIED TORQUES (LB-FT) ALLOWABLE LOADS (kN)
COMPRESSIVE TENSILE
500 20 4
750 24 8
1000 29 11
1250 34 14
1500 39 18
1750 44 21
2000 49 25
2250 53 31
2500 58 31
2750 63 35
3000 68 40
3250 73 44
3500 78 48
3750 82 50
4000 87 52
4250 92 54

ALLOWABLE LOADS (SLS) DEPENDING ON SOIL DENSITIES

SOIL DENSITY ALLOWABLE LATERAL LOAD (kN)
kN / m3 P178
18 0.8
20 0.9
22 1.0
SLS = Service Limit State

Technical Notes

  • For cohesionless soils, the safety factor varies from 2.0 to 3.0 in compressive loads and from 2.0 in tensile loads.
  • The safety factor for the lateral loads varies from 2.0 to 6.4, for cohesionless and cohesive soils.
  • If there are any boulders (> 200 mm in diameter ) in the granular matrix, the above mentioned capacities will be overstated. In this case, the allowable loads will have to be established on-site using a con rmatory test.

COHESIVE SOILS (CLAY)

ALLOWABLE LOADS (SLS) DEPENDING ON APPLIED TORQUES

APPLIED TORQUES (LB-FT) ALLOWABLE LOADS (kN)
COMPRESSIVE TENSILE
750 8 6
1000 11 8
1250 14 10
1500 17 12
1750 19 14
2000 22 16
2250 25 19
2500 28 21
2750 31 23
3000 33 25
3250 36 27
3500 39 29
3750 42 32
4000 44 34
4250 47 36
4500 50 38

ALLOWABLE LOADS (SLS) DEPENDING ON SOIL DENSITIES

SOIL DENSITY ALLOWABLE LATERAL LOAD (kN)
kN / m3 P178
16 0.7
SLS = Service Limit State

Technical Notes

  • For cohesive soils, the safety factor varies from 2.0 to 2.9 in compressive and in tensile loads.
  • The safety factor for the lateral loads varies from 2.0 to 6.4, for cohesionless and cohesive soils.
  • If there are any boulders (> 200 mm in diameter ) in the granular matrix, the above mentioned capacities will be overstated. In this case, the allowable loads will have to be established on-site using a con rmatory test.

picto trombone P178