Chance Technical Design Manual

ROCK

0.25 0.90 0.75 0.50 POOR FAIR GOOD EXCELLENT

DOLERITE

HUBBELL POWER SYSTEMS, INC. CHANCE ® HELICAL PILE / ANCHOR and ATLAS RESISTANCE ® PIER

BASALT

DIORITE

ROCK QUALITY DESIGNATION (RQD) 2

QUARTZITE

GRANITE

DOLOMITE

GNEISS

COMPETENT ROCK

LIMESTONE

Σ length of intact pieces of core > 100 mm length of core advance

SANDSTONE

SCHIST

METAMORPHIC ROCK 1

SEDIMENTARY ROCK 1 SHALE

PRODUCT SELECTION GUIDE

IGNEOUS ROCK 1

ATLAS RESISTANCE ® Piers

NOTES: 1. Range of RQD of Slightly Weathered to Competent Rock. 2. Rock Quality Designation (RQD) =

PRODUCT FEASIBILITY

0 6 10 17 25 30 40 50 65 80

S/C

VERY WEATHERED TO WEATHERED ROCK; CEMENTED SANDS; HARD CLAY SOILS

S/C

VERY DENSE

S C

HARD CLAYS

S C

S C

DENSE

CHANCE ® Helical Piles / Anchors

“N” (BLOWS PER FOOT)

SOIL

S C

VERY STIFF

S C

S C

STANDARD PENETRATION BLOW COUNT (per ASTM D1586)

MEDIUM

STIFF

C = CLAY

S = SAND

LOOSE

MEDIUM

SS125

SSS5

SS150

SS175

SS200, SS225

RS2875., RS3500 RS4500

SOFT TO

VERY

SOFT

VERY

LOOSE

SANDS

PRODUCT SERIES

SOIL

PRODUCT SELECTION GUIDE, FIGURE 3-1

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