Comm. D5.] PIN-CONNECTED MEMBERS 16.1–287

Specification for Structural Steel Buildings, June 22, 2010AMERICAN INSTITUTE OF STEEL CONSTRUCTION

D4. BUILT-UP MEMBERS

Although not commonly used, built-up member configurations using lacing, tieplates and perforated cover plates are permitted by this Specification. The length andthickness of tie plates are limited by the distance between the lines of fasteners, h,which may be either bolts or welds.

D5. PIN-CONNECTED MEMBERS

Pin-connected members are occasionally used as tension members with very largedead loads. Pin-connected members are not recommended when there is sufficientvariation in live loading to cause wearing of the pins in the holes. The dimensionalrequirements presented in Specification Section D5.2 must be met to provide for theproper functioning of the pin.

1. Tensile Strength

The tensile strength requirements for pin-connected members use the same φ and Ω values as elsewhere in this Specification for similar limit states. However, the definitions of effective net area for tension and shear are different.

2. Dimensional Requirements

Dimensional requirements for pin-connected members are illustrated in Figure C-D5.1.

Fig. C-D5.1. Dimensional requirements for pin-connected members.

Dimensional Requirements

1. a ≥ 1.33 be

2. w ≥ 2be + d3. c ≥ a

where

be = 2t + 0.63 in. (16 mm) ≤ b

16.1–288 EYEBARS [Comm. D6.

Specification for Structural Steel Buildings, June 22, 2010AMERICAN INSTITUTE OF STEEL CONSTRUCTION

D6. EYEBARS

Forged eyebars have generally been replaced by pin-connected plates or eyebarsthermally cut from plates. Provisions for the proportioning of eyebars contained inthis Specification are based upon standards evolved from long experience withforged eyebars. Through extensive destructive testing, eyebars have been found toprovide balanced designs when they are thermally cut instead of forged. The moreconservative rules for pin-connected members of nonuniform cross section and formembers not having enlarged “circular” heads are likewise based on the results ofexperimental research (Johnston, 1939).

Stockier proportions are required for eyebars fabricated from steel having a yieldstress greater than 70 ksi (485 MPa) to eliminate any possibility of their “dishing”under the higher design stress.

1. Tensile Strength

The tensile strength of eyebars is determined as for general tension members, exceptthat, for calculation purposes, the width of the body of the eyebar is limited to eighttimes its thickness.

2. Dimensional Requirements

Dimensional limitations for eyebars are illustrated in Figure C-D6.1. Adherence tothese limits assures that the controlling limit state will be tensile yielding of the body;thus, additional limit state checks are unnecessary.

Comm. D6.] EYEBARS 16.1–289

Specification for Structural Steel Buildings, June 22, 2010AMERICAN INSTITUTE OF STEEL CONSTRUCTION

Dimensional Requirements

t ≥ 1/2 in. (13 mm) (Exception is provided in Section D6.2)

w ≤ 8t

d ≥ 7/8w

dh ≤ d + 1/32 in. (1 mm)

R ≥ dh + 2b2/3w ≤ b ≤ 3/4w (Upper limit is for calculation purposes only)

Fig. C-D6.1. Dimensional limitations for eyebars.