b'MOTOR OUTPUT TORQUE vs ULTIMATE CAPACITYSquare Shaft 2-7/8" Dia 3-1/2" Dia 4-1/2" Dia240220200Ultimate Capacity x 1,000 lb.1801601405.MinimumEmbedment 120GRAPH 6 -MOTOR OUTPUT TORQUE vs ULTIMATE CAPACITYDepth. In Chapter 1 of the Graph 1.manual, there is a discussion 240 100Torque Efficiency Factor - "k" to Shaft Configurationabout helical products being 220 80deepfoundationelements.Sq. Shaft (k = 10)Theformulaspresented 2002" Sq. Bar (k = 8.5) 60 Earth Contact ProductsUltimate Capacity x 1,000 lb.180 2-7/8" Dia (k - 9)herein are based upon deep 160 3-1/2" Dia (k - 8) 40foundation theory.For the 4-1/2" Dia (k = 7)resultsofthecalculations, 140 20tablesandgraphstobe 120accurate,theremustbe 100 0sufficientsoilburdenover 80 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23theanchororpile.Deep 60 Graph 6.foundationtheorydictates 40 Graph 1. Motor Torque x 1000 ft-lbthattheminimumdepth 20fromthesurfacetothe 0shallowest plate must exceed 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23sixtimesthelargest plate Motor Torque x 1000 ft-lbdiameter.Minimum Embedment Depth: 7. Torque Anchor Selection:D = 6 x d largest plate o TAF-150-60 08-101-1/2 inch solid square(* The minimum depth equation cannot be used here.) shaft that has 8 & 10 diameter plates on a5-0 long shaft,*Notice: The soil information provided on thisTAE-150-60 & TAE-150-120 extension5projectstatedsoftsoilexisted directly below footextensionsection&hardware,(4-9the surface before reaching the targeted stiff to effective length) and 10 foot extension (9-9very stiff clay below 10 feet. The calculated effective length).MinimumVerticalDepthforthisdesignTAB-150 NC Pile Cap that fits over the 1-would be 5 ft.This is invalid.The pile must 1/2squarebarandhasa1/2x6x6be at 18 feet as specified by the engineer. bearing plate.D (Engr Reqd)= Minimum Vertical Depth = 18 ft Total pile length is 19-1/2 feet.6.Minimum Required Shaft Length - The Final Shaft Torque = 1,800 ft-lb, minimumleastamountofshaftrequiredto meetthe Itrecommendedhavingadditionalextensionsdesign requirement is a 5 foot lead section, a 5 on hand should the target shaft torsion of 1,800foot extension and a 10 foot extension. ft-lbs not be achieved at 19-1/2 feet shaft depth.Additional extensions could be required if the End of Example 2Atorsionrequirementof1,800ft-lbisnotachieved at the 18 ft depth.Review of Results of Example 2 & 2AOne can see that the result obtained by the Quick -Solve analysis clearly suggested the same piledesign as determined by the calculated analysis.Therefore the TAF-150 08-10 is a valid design andshould work well on this project.Recall that the specified depth was 18 feet of shaft that terminatedone foot below grade.* NOTE: The Quick -Solvemethod for Example 2A is not able to compensate for the fill soil near thesurface.Recall that the graphs are based upon capacities of helical piles installed into homogeneoussoil, which means that the soil is consistent at all depths.Clearly this is not the case in this examplebecause of the weak upper strata of fill soils.A pile installation deeper than 19 feet might be requiredto support the load.ECP Technical Design ManualTorque Anchor Design Examples2021 Earth Contact Products, L.L.C.2021-09 Chapter 5Page 88 All rights reserved'