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WAC 296-155-709

Open web steel joists.

(1) General.
(a) Where steel joists are used and columns are not framed in at least two directions with solid web structural steel members, a steel joist must be field-bolted at the column to provide lateral stability to the column during erection.
Exception:
See (b) of this subsection. For the installation of this joist:
 
(i) A vertical stabilizer plate must be provided on each column for steel joists. The plate must be a minimum of 6 inch by 6 inch (152 mm by 152 mm) and must extend at least 3 inches (76 mm) below the bottom chord of the joist with a 13/16-inch (21 mm) hole to provide an attachment point for guying or plumbing cables.
 
(ii) The bottom chords of steel joists at columns must be stabilized to prevent rotation during erection.
 
(iii) You must not release hoisting cables until the seat at each end of the steel joist is field-bolted, and each end of the bottom chord is restrained by the column stabilizer plate.
(b) Where constructibility does not allow a steel joist to be installed at the column:
(i) You must install an alternate means of stabilizing joists on both sides near the column and it must:
• Provide stability equivalent to (a) of this subsection;
• Be designed by a qualified person;
• Be shop installed; and
• Be included in the erection drawings.
(ii) You must not release hoisting cables until the seat at each end of the steel joist is field-bolted and the joist is stabilized.
(c) Where steel joists at or near columns span 60 feet (18.3 m) or less, the joist must be designed with sufficient strength to allow one employee to release the hoisting cable without the need for erection bridging.
(d) Where steel joists at or near columns span more than 60 feet (18.3 m), the joists must be set in tandem with all bridging installed unless an alternative method of erection, which provides equivalent stability to the steel joist, is designed by a qualified person and is included in the site-specific erection plan.
(e) You must not place a steel joist or steel joist girder on any support structure unless such structure is stabilized.
(f) When steel joist(s) are landed on a structure, you must secure them to prevent unintentional displacement prior to installation.
(g) You must not make any modification that affects the strength of a steel joist or steel joist girder without the approval of the project structural engineer of record.
(h) Field-bolted joists.
(i) Except for steel joists that have been preassembled into panels, connections of individual steel joists to steel structures in bays of 40 feet (12.2 m) or more must be fabricated to allow for field bolting during erection.
(ii) These connections must be field-bolted unless constructibility does not allow.
(i) You must not use steel joists and steel joist girders as anchorage points for a fall arrest system unless written approval to do so is obtained from a qualified person.
(j) You must establish a bridging terminus point before bridging is installed. (See Appendix E to this part.)
(2) Attachment of steel joists and steel joist girders.
(a) You must attach each end of "K" series steel joists to the support structure with a minimum of two 1/8-inch (3 mm) fillet welds one inch (25 mm) long or with two 1/2-inch (13 mm) bolts, or the equivalent.
(b) You must attach each end of "LH" and "DLH" series steel joists and steel joist girders to the support structure with a minimum of two 1/4-inch (6 mm) fillet welds two inches (51 mm) long, or with two 3/4-inch (19 mm) bolts, or the equivalent.
(c) Except as provided in (d) of this subsection, you must attach each steel joist to the support structure, at least at one end on both sides of the seat, immediately upon placement in the final erection position and before additional joists are placed.
(d) You must attach panels that have been preassembled from steel joists with bridging to the structure at each corner before the hoisting cables are released.
(3) Erection of steel joists.
(a) You must attach both sides of the seat of one end of each steel joist that requires bridging under Tables A and B to the support structure before hoisting cables are released.
(b) For joists over 60 feet, you must attach both ends of the joist as specified in subsections (2) and (4) of this section before the hoisting cables are released.
(c) On steel joists that do not require erection bridging under Tables A and B, you must only allow one employee on the joist until all bridging is installed and anchored.
Table A—Erection of Bridging for Short Span Joists
Joist
Span
 
Joist
Span
 
Joist
Span
8L1
NM
 
22K10
40-0
 
14KCS1
NM
10K1
NM
 
22K11
40-0
 
14KCS2
NM
12K1
23-0
 
24K4
36-0
 
14KCS3
NM
12K3
NM
 
24K5
38-0
 
16KCS2
NM
12K5
NM
 
24K6
39-0
 
16KCS3
NM
14K1
27-0
 
24K7
43-0
 
16KCS4
NM
14K3
NM
 
24K8
43-0
 
16KCS5
NM
14K4
NM
 
24K9
44-0
 
18KCS2
35-0
14K6
NM
 
24K10
NM
 
18KCS3
NM
16K2
29-0
 
24K12
NM
 
18KCS4
NM
16K3
30-0
 
26K5
38-0
 
18KCS5
NM
16K4
32-0
 
26K6
39-0
 
20KCS2
36-0
16K5
32-0
 
26K7
43-0
 
20KCS3
39-0
16K6
NM
 
26K8
44-0
 
20KCS4
NM
16K7
NM
 
26K9
45-0
 
20KCS5
NM
16K9
NM
 
26K10
49-0
 
22KCS2
36-0
18K3
31-0
 
26K12
NM
 
22KCS3
40-0
18K4
32-0
 
28K6
40-0
 
22KCS4
NM
18K5
33-0
 
28K7
43-0
 
22KCS5
NM
18K6
35-0
 
28K8
44-0
 
24KCS2
39-0
18K7
NM
 
28K9
45-0
 
24KCS3
44-0
18K9
NM
 
28K10
49-0
 
24KCS4
NM
18K10
NM
 
28K12
53-0
 
24KCS5
NM
20K3
32-0
 
30K7
44-0
 
26KCS2
39-0
20K4
34-0
 
30K8
45-0
 
26KCS3
44-0
20K5
34-0
 
30K9
45-0
 
26KCS4
NM
20K6
36-0
 
30K10
50-0
 
26KCS5
NM
20K7
39-0
 
30K11
52-0
 
28KCS2
40-0
20K9
39-0
 
30K12
54-0
 
28KCS3
45-0
20K10
NM
 
10KCS1
NM
 
28KCS4
53-0
22K4
34-0
 
10KCS2
NM
 
28KCS5
53-0
22K5
35-0
 
10KCS3
NM
 
30KCS3
45-0
22K6
36-0
 
12KCS1
NM
 
30KCS4
54-0
22K7
40-0
 
12KCS2
NM
 
30KCS5
54-0
22K9
40-0
 
12KCS3
NM
 
 
 
NM
=
Diagonal bolted bridging not mandatory for joists under 40 feet.
Table B—Erection Bridging for Long Span Joists
Joist
Span
 
Joist
Span
18LH02
33-0
 
28LH06
42-0
18LH03
NM
 
28LH07
NM
18LH04
NM
 
28LH08
NM
18LH05
NM
 
28LH09
NM
18LH06
NM
 
28LH10
NM
18LH07
NM
 
28LH11
NM
18LH08
NM
 
28LH12
NM
18LH09
NM
 
28LH13
NM
20LH02
33-0
 
32LH06
47-0 through 60-0
20LH03
38-0
 
32LH07
47-0 through 60-0
20LH04
NM
 
32LH08
55-0 through 60-0
20LH05
NM
 
32LH09
NM through 60-0
20LH06
NM
 
32LH10
NM through 60-0
20LH07
NM
 
32LH11
NM through 60-0
20LH08
NM
 
32LH12
NM through 60-0
20LH09
NM
 
32LH13
NM through 60-0
20LH10
NM
 
32LH14
NM through 60-0
24LH03
35-0
 
32LH15
NM through 60-0
24LH04
39-0
 
36LH07
47-0 through 60-0
24LH05
40-0
 
36LH08
47-0 through 60-0
24LH06
45-0
 
36LH09
57-0 through 60-0
24LH07
NM
 
36LH10
NM through 60-0
24LH08
NM
 
36LH11
NM through 60-0
24LH09
NM
 
36LH12
NM through 60-0
24LH10
NM
 
36LH13
NM through 60-0
24LH11
NM
 
36LH14
NM through 60-0
28LH05
42-0
 
36LH15
NM through 60-0
NM
=
Diagonal bolted bridging not mandatory for joists under 40 feet.
(d) You must not allow employees on steel joists where the span of the steel joist is equal to or greater than the span shown in Tables A and B except in accordance with WAC 296-155-709(4).
(e) When permanent bridging terminus points cannot be used during erection, additional temporary bridging terminus points are required to provide stability. (See Appendix E of this part.)
(4) Erection bridging.
(a) Where the span of the steel joist is equal to or greater than the span shown in Tables A and B, the following applies:
(i) You must install a row of bolted diagonal erection bridging near the midspan of the steel joist;
(ii) You must not release hoisting cables until this bolted diagonal erection bridging is installed and anchored; and
(iii) You must not allow more than one employee on these spans until all other bridging is installed and anchored.
(b) Where the span of the steel joist is over 60 feet (18.3 m) through 100 feet (30.5 m), the following applies:
(i) All rows of bridging must be bolted diagonal bridging;
(ii) You must install two rows of bolted diagonal erection bridging near the third points of the steel joist;
(iii) You must not release hoisting cables until this bolted diagonal erection bridging is installed and anchored; and
(iv) You must not allow more than two employees on these spans until all other bridging is installed and anchored.
(c) Where the span of the steel joist is over 100 feet (30.5 m) through 144 feet (43.9 m), the following applies:
(i) You must bolt all rows of bridging diagonal bridging;
(ii) You must not release hoisting cables until all bridging is installed and anchored; and
(iii) You must not allow more than two employees on these spans until all bridging is installed and anchored.
(d) For steel members spanning over 144 feet (43.9 m), the erection methods used must be in accordance with WAC 296-155-708.
(e) Where any steel joist specified in subsections (3)(b), (4)(a), (b), and (c) of this section is a bottom chord bearing joist, you must provide a row of bolted diagonal bridging near the support(s). You must install and anchor this bridging before the hoisting cable(s) is released.
(f) When bolted diagonal erection bridging is required by this section, the following applies:
(i) The bridging must be indicated on the erection drawing;
(ii) The erection drawing must be the exclusive indicator of the proper placement of this bridging;
(iii) You must use shop-installed bridging clips, or functional equivalents, where the bridging bolts to the steel joists;
(iv) When two pieces of bridging are attached to the steel joist by a common bolt, you must not remove the nut that secures the first piece of bridging from the bolt for the attachment of the second; and
(v) Bridging attachments must not protrude above the top chord of the steel joist.
(5) Landing and placing loads.
(a) During the construction period, the employer placing a load on steel joists must ensure that the load is distributed so as not to exceed the carrying capacity of any steel joist.
(b) Except for (d) of this subsection, no construction loads are allowed on the steel joists until all bridging is installed and anchored and all joist-bearing ends are attached.
(c) The weight of a bundle of joist bridging must not exceed a total of 1,000 pounds (454 kg). You must place a bundle of joist bridging on a minimum of 3 steel joists that are secured at one end. The edge of the bridging bundle must be positioned within one foot (.30 m) of the secured end.
(d) No bundle of decking may be placed 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:
(i) The employer has first determined from a qualified person and documented in a site-specific erection plan that the structure or portion of the structure is capable of supporting the load;
(ii) The bundle of decking is placed on a minimum of 3 steel joists;
(iii) The joists supporting the bundle of decking are attached at both ends;
(iv) At least one row of bridging is installed and anchored;
(v) The total weight of the bundle of decking does not exceed 4,000 pounds (1816 kg); and
(vi) Placement of the bundle of decking must be in accordance with (e) of this subsection.
(e) The edge of the construction load must be placed within one foot (.30 m) of the bearing surface of the joist end.
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. WSR 16-09-085, § 296-155-709, filed 4/19/16, effective 5/20/16. Statutory Authority: RCW 49.17.010, [49.17].040, and [49.17].050. WSR 02-13-115, § 296-155-709, filed 6/19/02, effective 9/1/02.]
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