513 EM 385-1-1 Chapters 23-29

Sections

28-8. General Requirements.

Erection Bridging

Install bolted diagonal erection bridging as specified by span and table requirements. Do not release hoisting cables or allow more than the specified number of employees on the span until bridging is properly installed and anchored.
For spans over 60 feet and up to 144 feet, use only bolted diagonal bridging, install it at designated points, and follow specific employee limits until all bridging is secured.
For bottom chord-bearing joists and when bridging is required, indicate bridging on erection drawings, use specified attachments, and ensure bridging does not protrude above the top chord.

Landing and Placing Loads

The employer must ensure loads on steel joists are distributed without exceeding their carrying capacity. Construction loads must not be placed until all bridging and joist-bearing ends are secured.
Bundle weights and placement must meet specified limits. If placing bundles of decking, certain conditions including a documented Steel Erection Plan by a QP and specific placement and weight restrictions must be met.

Systems-Engineered Metal Buildings

Adhere to all chapter requirements except specified exceptions. Ensure structural columns, rigid frames, and other framework elements are properly anchored and secured before proceeding with further construction or placing loads.
Follow specific guidelines for girt and eave strut connections, use of purlins and girts, and placement of construction loads relative to primary support members.
Implement measures for falling object protection and prohibit CDZ (Controlled Decking Zones).

28-9. Figures and Tables.

See Figures/Tables Checklists/Forms

29-10. Checklists and Forms.

Not Applicable.

Knowledge Check Choose the best answer for the question.

28-9. Use only bolted diagonal bridging for spans _____.

under 60 feet

over 40 feet up to 100 feet

over 60 feet and up to 144 feet

greater than 80 feet in length

You forgot to answer the question!

EM 385-1-1 Paragraph 28-8 (v.–x).

28-8. General Requirements.(v.–x).

v.  Erection bridging.  (28-8.v)

(1)  Where the span of the steel joist is equal to or greater than the span shown in tables 28-1 and 28-2, follow these requirements:

(a)  Install a row of bolted diagonal erection bridging near the mid-span of the steel joist.

(b)  Do not release hoisting cables until the required bolted diagonal erection bridging is installed and anchored, see table 28-1.

(2)  Where the span of the steel joist is over 60 feet (18.3 m) and up to 100 feet (30.5 m), follow these requirements:

(a) All rows of bridging must be bolted diagonal bridging.

(b)  Install two rows of bolted diagonal erection bridging near the third points of the steel joist.

(d)  Do not allow more than two employees on these spans until all other bridging is installed and anchored.

(3)  Where the span of the steel joist is over 100 feet (30.5 m) and up to 144 feet (43.9 m), follow these requirements:

(a) All rows of bridging must be bolted diagonal bridging.

(b)  Do not release hoisting cables until all bridging is installed and anchored. (c)  Do not allow more than two employees on these spans until all bridging is installed and anchored.

(4)  For steel members spanning over 144 feet (43.9 m), the erection methods used must follow paragraphs 28-8.n. through q.

(5)  Where any steel joist specified in paragraph 28-8.v(2) above or paragraphs 28-8.w(1) through (3) is a bottom chord-bearing joist, provide a row of bolted diagonal bridging near the supports.  Install this bridging and anchor it before releasing the hoisting cables.

(6)  When bolted diagonal erection bridging is required by paragraph 28-8.v follow these requirements:

(a)  Indicate the bridging on the erection drawing.

(b)  Use the erection drawings as the exclusive indicator of the proper placement of this bridging.

(c)  Use shop-installed bridging clips or functional equivalents where the bridging bolts to the steel joists (see figures 28-1, 28-2 and 28-5).

(d)  When two pieces of bridging are attached to the steel joist by a common bolt, do not remove the nut that secures the first piece of bridging from the bolt when attaching the second piece of bridging.

(e)  Do not allow bridging attachments to protrude above the top chord of the steel joist.

w.  Landing and Placing Loads.  (28-8.w)

(1)  During the construction period, the employer must ensure that when placing a load on steel joists the load is distributed so it does not exceed the carrying capacity of any steel joist.

(2)  Except as stated in paragraph 28-8.w(4) below, do not place construction loads on the steel joists until all bridging is installed and anchored and all joist-bearing ends are attached.

(3) The weight of a bundle of joist bridging may not exceed a total of 1,000 lbs. (454 kg). Place each bundle of joist bridging on a minimum of three steel joists that are secured at one end. Position the edge of the bridging bundle within 1 foot (0.3 m) of the secured end.

(4)  Do not place any bundles of decking on steel joists until all bridging has been installed and anchored and all joist bearing ends attached, unless all of the following conditions are met:

(a) A QP has documented in a site-specific Steel Erection Plan that the structure or portion of the structure can support the load.

(b) The bundle of decking is placed on a minimum of three steel joists.

(d) At least one row of bridging is installed and anchored.

(e) The total weight of the bundle of decking does not exceed 4,000 lbs. (1814.4 kg), and the edge of the construction load is placed within 1 foot (0.3 m) of the bearing surface of the joist end.

x.  Systems-Engineered Metal Buildings.  (28-8.x)

(1) All of the requirements of this chapter apply to the erection of systems- engineered metal buildings except paragraph 28-8.m (column anchorage) and paragraph 28-8.s (open web steel joists).

(a) Anchor each structural column using a minimum of four anchor rods or anchor bolts.

(b)  Rigid frames must have 50% of their bolts or the number of bolts specified by the manufacturer, whichever is greater, installed and tightened on both sides of the web adjacent to each flange, before the hoisting equipment is released.

(c)  Do not place construction loads on any structural steel framework unless such framework is safely bolted, welded, or otherwise adequately secured.

(d)  In girt and eave strut-to-frame connections, where girts or eave struts share common connection holes, at least one bolt with its snug tight nut must remain connected to the first member. The exception to this is when a manufacturer-supplied, field-attached seat or similar connection device is present to secure the first member so that the girt or eave strut is always secured against displacement.

(e)  Do not use purlins and girts as an anchorage point for a PFAS unless a QP for
        Fall Protection provides written approval to do so.

(f)  Do not use purlins as a walking or working surface when installing safety systems until all permanent bridging has been installed and fall protection is provided.

(g)  Only place construction loads within a zone that is within 8 feet (2.4 m) of the centerline of the primary support member.

(h)  Fully bolt or weld both ends of all steel joists or cold-formed joists to the support structure before releasing the hoisting cables, allowing an employee on the joist, or allowing any construction loads on the joists.

(2)  Falling object protection.

(a)  Securing loose items aloft.  Secure all materials, equipment, and tools that are not in use while aloft against accidental displacement.

(b)  Provide protection from falling objects other than materials being hoisted. The controlling contractor must not allow other construction processes below steel erection unless overhead protection for the employees below is provided.

(3)  CDZ are not permitted.