b'Design Example 2ALight Weight New ConstructionQuick-Solve Design MethodDesign Details from Design Example 2: shaft withan AxialCompressionLoadLimit The ultimate capacity on each pile spaced at 7 ratingof70,000poundsbaseduponanfeet on center is 18,000 pounds installation torsional limit of 7,000 ft-lbs.The Top of shaft to be one foot below soil surface selectedpileshaftprovidessuitable Useable Soil data: TorsionalStrengthandasufficientpractical4 feet of poorly compacted fill followed by 6 loadlimittoexceed allof the designfeet of silty clay (CH) over 15 feet of very stiff requirements. Table 9 in Chapter 1 shows anclay (CL) Ultimate Mechanical Helical Plate Capacity ofECP Torque Anchor Design: Because this is 80,000pounds(40,000lbx2)fortwo3/8acompressiveloadapplicationandthereexists thickhelicalplatesontheshaft.Thepilesomepoorlycompactedfill, theSoilClass configuration is TAF-150-60 08-10.selection of must be conservative. 4. InstallationTorque: Use Graph1from1.Determine the Soil Class: Referring to the Chapter 4; (Please see on next page) or can beSoil Classification Table (Table 9Chapter 1) determined from Equation 2 from Chapter 1 toand recalling that the soil on the site is very stiff determinetheinstallationtorquerequirementclay, SoilClass4isselected.Thepoorly forthesepiles.Find18,000lbultimatecompactedfillshouldnotbeaproblematthis capacity value on the left side of Graph 1 andlightloadingaslongasthehelicalplatesare locate the intersection with the graph line for ainstalled into the underlying very stiff clay. solidsquareshaft.Thenreaddownto2. Select the proper compression pile determinethemotortorquerequirementofconfigurationfrom the TORQUE ANCHOR HOLDING CAPACITYestimated capacity Multiple Helical Plate Sizesgraphs: 8-8" 8-10" 10-10" 10-12"Referring to Graph 700003fromChapter1Estimated Ultimate Capacity(reproducedright), 60000noticethatthe 50000capacity line for ananchor with an 8 & 4000010 diameter helicalplatesattached 30000crossesthemidpointofSoil 20000Class4at 30,000lb.The 810 inch 10000 Earth Contact Productsdiameterplateconfigurationis 0selectedforthe Graph 3. 17 26 3 5 4 4 5 3 6design. (Two8 Soil Classificationdiameter plates also have sufficient capacity of 1,800 ft-lb. T = 1,800 ft-lb, minimum22,500lb,buttheconfigurationisaspecialorder product.) To calculate the installation torque, use3.ChecktheShaftStrengthandTorsional Equation 2.(Shown here for comparison)Strength to select a suitable shaft. Refer to T = P u/ k,Table 2 in Chapter 1 to locate a shaft with a Where; P u= 18,000 lb k = 10 (Table 12)higher than 18,000 lb. Axial Compression Load T = 18,000 lb / 10 ft -1= 1,800 ft-lbLimitand a sufficient UseableTorsional T = 1,800 ft-lb, minimumO.K.Strength. Selectthe1-1/2inchsolidsquareECP Technical Design ManualTorque Anchor Design Examples2021 Earth Contact Products, L.L.C.2021-09 Chapter 5Page 87 All rights reserved'