Transmission And Substation Foundations - Technical Design Manual

SECTION 6: PRODUCT DRAWINGS AND RATINGS Type SS/RS Combination Helical Piles

Helical Transition Coupler

Adapts Type SS to Type RS Pile Shafts The Type SS/RS Combination Pile is used mainly in

compression applications in areas where soft/loose soils are located above the bearing strata (hard/dense soils) for the helices. The Type RS material with its much greater section modulus will resist columnar buckling in the soft/loose soil. Its larger shaft diameter also provides for lateral load resistance. Due to its slender size, the Type SS material provides the means for the helix plates to penetrate deeper into hard/dense soil strata than if the helical pile shaft was round shaft only. For a given helix configuration and equal available installation energy (i.e., machine), a small-displacement shaft will penetrate farther into a soil bearing stratum than a large-displacement shaft and will disturb less soil. It is recommended that a Chance SS/RS Combination Pile be used in all projects where round shaft is being used. The square shaft lead section will provide better load capacity and less settlement than a comparable straight round shaft pile. The transition coupler (see Figure 6-45) adapts Type SS helical lead sections to Type RS plain extensions. Installation of this combination pile is the same as a standard helical pile. Table 6-4 provides the various standard transition couplers that are available along with their ratings. Special transition couplers, such as RS2875 to RS4500, are also available. Please contact your area Chance distributor for availability and delivery times.

Transition Couplers, Table 6-4

Torque Ratings

Description

K t

Catalog No.

SS5 square shaft to RS2875.203 round shaft SS150 square shaft to RS2875.203 round shaft SS150 square shaft to RS2875.276 round shaft SS175 square shaft to RS2875.276 round shaft SS175 square shaft to RS3500.300 dia round shaft SS200 square shaft to RS3500.300 dia round shaft

C1071639

5,700 ft∙lb 9.5

C1071639

7,000 ft∙lb 9.5

C1071639

7,000 ft∙lb 9.5

C1101456

8,000 ft∙lb 9.5

C1071515

10,500 ft∙lb 8.5

C1101458

13,000 ft∙lb 8.5

SS200 square shaft to RS4500 round shaft SS225 square shaft to RS4500 round shaft

C1101443

16,000 ft∙lb 7

C1101418

21,000 ft∙lb 7

Pile Assembly with Transition Coupler Figure 6-45

6-74 | www.hubbell.com/hubbellpowersystems