1118 80TH ST SW BASE FILE 2022-01-24

ESR-3969 I Most Widely Accepted and Trusted Page 7 of 10 TABLE 1—BRACKET CAPACITY(P1)FOR DIRECT LOAD BRACKETS (P1)ALLOWABLE CAPACITY(kips) 2,500 psi Concrete Minimum BRACKET PRODUCT SHAFT DIAMETER TYPE NUMBER (inches) Compression Tension Lateral Type A (Side Load) 2.88-TLB 27/8 27.9 N/A N/A Bracket Type B1'2 (Direct Load) 2.88-NCB 27/8 43.53 N/A N/A Bracket For SI: 1 kip=4.448 kN,1 psi=6.895 kPa. 'Only localized limit states of supporting concrete including bearing and 2-way punching shear have been evaluated.Refer to Sections 5.4 and 5.9 of this report for additional requirements. 2Allowable capacities include an allowance for corrosion over a 50-year service life and presume the supported structure is braced in accordance with IBC Section 1810.2.2. 3The allowable compressive load capacity is based on the mechanical strength of the steel bracket,concrete punching shear capacity, and concrete bearing strength.The allowable load capacities have been determined assuming that minimum reinforcement has been provided as specified by ACI 318-14 Section 9.6.1.2 and ACI 318-11 Section 10.5.1.The minimum embedment of the bracket is 11.30-inches. The embedment depth is the distance between the top of the bracket plate to the top of the concrete footing.The end of helical pile shaft must be fully bearing on bracket plate.For Type B bracket,the concrete footing must have a minimum thickness of 15.8-inches and a minimum width of 28.6-inches,and must be normal-weight concrete having a minimum compressive strength of 2,500 psi. TABLE 2(A)—27/8-INCH SHAFT ALLOWABLE CAPACITY(P2)1 (P2)ALLOWABLE CAPACITY(KIPS) UNBRACED COMPRESSION2'3 SHAFT LENGTH, TENSION LATERAL kL(FT) 0 Coupler 1 Coupler 2 Couplers 0 50 21.3 10.8 NE4 NE4 5 18.0 12.9 6.5 NE4 NE4 10 7.9 6.7 5.0 NE4 NE4 For SI: 1 inch=25.4 mm, 1 kip=4.448 kN. 'Allowable capacities include an allowance for corrosion over a 50-year service life. 2Allowable capacities are based on fully braced conditions where effective length(kL)of piles equals to zero and pile tops are fully braced,which require the pile head to be fully braced laterally and rotationally and no portion of shaft is in air,water,or fluid soils.Refer to Section 4.1.3 of this report for the determination of unbraced length,L. 3 For other unbraced lengths,the shaft capacity of helical foundations must be determined by a registered design professional. 4NE=Not evaluated at this time. TABLE 2(B)—MECHANICAL PROPERTIES AFTER CORROSION LOSS1 OF 2.875-INCH DIAMETER HELICAL SHAFT MECHANICAL PROPERTIES 2.875-INCH(0.217-INCH WALL THICKNESS) Steel Yield Strength,Fy(ksi) 60 Steel Ultimate Strength,Fu(ksi) 63 Modulus of Elasticity,E(ksi) 29,000 Nominal Wall Thickness(inch) 0.217 Design Wall Thickness(inch) 0.166 Outside Diameter(inch) 2.839 Inside Diameter(inch) 2.507 Cross Sectional Area(inch) 1.39 Moment of Inertia,I(inch') 1.25 Radius of Gyration,r(inch) 0.95 Section Modulus,S(inch3) 0.88 Plastic Section Modulus,Z(inch3) 1.19 For SI: 1 inch=25.4 mm; 1 ksi=6.89 MPa,1 ft-lbf=1.36 N-m; 1 Ibf=4.45 N. 'Dimensional properties are based on bare steel losing 0.036-inch steel thickness as indicated in Section 3.9 of AC358 for a 50-year service life. I9e22