b'BearingCapacityisdependantuponmany Table 3. Symbols Used In This Chapterfactors: Kind Of Soil, A Projected area of Earth Anchor Plate ft 2 Soil Properties, c Undrained shear strength of the soil lb/ft 2 Surface Drainage D W Soil depth to basement wall penetration ft Ground Water Conditions, D min Depth to Earth Plate The distance from ground surface to the Size of Earth Anchor Plate top of the soil plate. D min=d w+ 1 ft(Minimum) Vertical Embedment, F.S. Factor Of Safety (MinimumFS = 1.5) Horizontal Embedment, H Height of soil against wall of basement- ft Earth Anchor Spacing, L MIN Horizontal embedment length-L min= H x 1.5The design of Earth Plate Anchors uses classical N c Bearing capacity factor for clay soilgeotechnicaltheoryandanalysisalongwith N q Bearing capacity factor for granular soilempirical relationships that have been developed P HM Horizontal force on wall from moist soilfromfieldloadtesting.Themostaccurate P HS Horizontal force on wall from saturated soildesign requires knowledge from field soil testing q Weight of soil at Earth Anchor depth lb/ft 2usingtheStandardPenetrationTest(SPT) S Height of Soil SurchargeAbove Retaining Wall- (ft)standardizedtoASTMD1586pluslaboratoryevaluationsof thesoilshearstrength,whichis T MAX Maximum Tension Capacity lb (No FS)usually given as soil cohesionc, soil density T SL Tension Service (Working) Load lb , and granular friction angle X Anchor spacing along the wall- ftUsingclassicalgeotechnicaltheory,the N Standard Penetration Test (SPT) N = Number of blows withmaximumcapacityofanECPEarthPlate a 140 lb hammer to penetrate the soil a distance of one foot.Anchorcanbecalculatedfromthefollowing EarthPlateAnchors whenembeddedfivefeetequation: into either100%claysoil or 100%sand.Equation 1 Maximum Theoretical Capacity: MidwaybetweentheclayandsandlinesisaT MAX = A (c N c+ q N q ) dashed line that represents a soil that consists ofequal parts sand and clay.This equation determines the Maximum Tensile ThegraphsreportFactoredServiceLoadCapacityofananchorbymultiplyingthe (T SL ) capacities within any clay/sand mixtureprojected area of the Earth Plate Anchor by the over a range of soil strengths between SPT sum of the strength of the clay component and N = 2 and 4 blows per foot.strength of the granular component in the soil.Because Earth Plate Anchor products are usually How to use the graphs: A proper and accurateselectedfortheireconomy,engineeringadvice designrequiressoildataandengineeringand geotechnical information are usually in the analysis.Becausethisanchoringproductisbudget.Typically the installing contractor must normallyusedtomakequickandinexpensiveperformtheanalysis,designandproduct repairs, soil and engineering input are normallyselection on these projects. notbelowtohelptheinstallerarriveatareasonableestimateoftheexpectedFactoredInordertoassistwithdesignandselectionof ServiceLoad (T SL )availableforagivenECPECP Earth Plate Anchors, we offer a simplified Earth Anchor Plate.process that is based upon classical theory alongwith known empirical data.In addition, general Beforethegraphscanbeused,theinstallerassumptionsaboutthesoilcomposition froma must estimate the composition of the soil andsite examination and estimated soil strength must soil strength from data collected from a testbe determined by the installer before attempting holedugneartheproposedEarthAnchorto complete a design. Plate installations at the site. A field estimateInthegraphspresented nextpagewehave of the ratio between clay and sand is neededcalculatedthe Estimated Factored Service along with an estimate of the soil strength atLoad Capacity(T SL )x(F.S.=1.5) forECP the anticipated installation depth of the EarthAnchor Plate.ECP Helical Plate Anchors Technical Service Manual2021 Earth Contact Products, L.L.C.2021-09 Chapter 2 - Page 41 All rights reserved'