The version provides the latest industry standard information as to the sale, manufacture and installation of steel deck. May This publication provides updated industry standard information as to the sale, manufacture and installation of steel deck. The manual is based on research, testing, and analysis sponsored by the Steel Deck Institute and its member and associate member companies, under the direction of Dr.
Larry D. The manual explains the method developed to calculate the capacity of diaphragms using steel roof decks or composite steel floor decks and the use of the diaphragm load tables.
With over pages of diaphragm load tables using welds, screws and other mechanical fasteners, the manual is a comprehensive resource for the design profession.
SDI home Manuals and Handbooks. This includes load tables and design examples for concentrated loads and scissor lift type moving loads. All of the load tables have now been made easier to read. Considerations for sound transmission and impact have also been included. Load tables are now based on 40 ksi material. Bundles of deck which have been unbanded must be secured to prevent individual sheets from being blown off the structure.
Check for tightness. Bundle straps are not to be used to move or lift deck bundles. If deck sheets are temporarily used to access bundles, they must be end bearing not cantilevered and must be securely attached to the frame to prevent slip off.
A working area should be at least 12 feet wide. It is recommended that a working area be established around or along each bundle so that the bundle can safely be accessed.
The platform can then be extended in any convenient direction. Specific job requirements need to be considered to determine deck erection starting points and erection progression. As the platform is extended it will be necessary for at least one worker to work from the structural frame.
OSHA standards require that employers provide fall protection during deck erection operations and all OSHA guidelines for safety while erecting deck must be followed.
This leading edge should only be approached in order to place the next sheet. Workers should also maintain a safe distance 6 feet if possible from the end of the deck unit. When aligning the edge side lap, the worker should kneel.
Kneeling low- ers his center of gravity and decreases the chance of falling. Roof and floor holes and openings shall be decked over, unless the size of the hole or special design circumstances prevent it from being decked over. It is the responsibility of the design profession- al to define whether a hole is required to be decked over.
Where large size holes or other conditions that do not allow an opening to be decked over, employees shall be protected in accordance with OSHA Regulation 29 CFR Section Care must be taken when cutting bundle straps to prevent straps or dunnage from dropping onto personnel or equipment. Workers should be instructed on all aspects of deck safety before any deck is installed. Non-union sources may also be available.
Floor deck should be selected so that it provides at least fifty pounds per square foot capacity as a working platform. If tempo- rary shoring is required to attain fifty pounds per square foot, then the shoring must be securely in place before the floor deck erection begins.
The fifty-pound per square foot loading does not consider concrete weight. See Figure 16 for recommended loading of the deck as a concrete form. Roof deck is not generally required to carry as much foot traffic as floor deck, but at least thirty pounds per square foot should be made available by roof deck. If the roof deck being used does not provide a platform capacity of 30 psf, then it should be planked or supported during erection.
Areas subject to traffic or material stag- ing should be planked. The maximum recommended spans for roof decks see Figure 15 should also be used as a guide. A steel deck surface is inherently slippery when wet. Caution is required by anyone on the deck when this condition exists. Make sure that rigging is adjusted to keep hoisted loads well balanced.
Do not stand under loads being hoisted. Keep loads in view. Use proper hand signals to crane operators. Check erection drawings to land deck in proper position and orientation to avoid turning deck. Make sure bundles are secure and stable before cutting bands.
Pay particular attention to single span bundles. Do not use single span bundles as a working platform, especially to cut bands. Sheets could shift due to handling. Ensure bottom sheet extends past the support at both ends, otherwise place where full support can be obtained. When cutting bands on bundles use both hands and stand well back - bands are under tension.
Eye protection is recommended. Pay special attention to short units or single span units— make sure deck is firmly secured before using it as a working platform.
Make sure cut outs and openings are adequately supported and guarded. Use chalk lines to locate supporting steel - measure accurately. Be alert for sharp edges. Wet deck is inherently slippery - watch your footing. Keep a litter free work place.
Wear eye protection when near welding. When installing galvanized deck on sunny days, sunglasses and sunburn protection are advisable. Stay alert. The deck must be installed by qualified and expe- rienced workers.
The beginning point should be carefully selected for proper deck orientation and edge of roof or floor slab location. Maintaining rib or flute alignment across the structure is very important. A snap chalk line should be used at reasonable intervals to assure proper alignment of deck panels. Panel cover widths must be maintained to achieve long straight runs of deck. Roof deck is often left exposed on the bottom. Rib alignment must be parallel to the girders at all girder lines to prevent un- sightly conditions.
Floor deck flutes should, if possible, maintain alignment to achieve continuous concrete ribs across abutting sheet ends, mini- mizing concrete leakage. Flutes that do not align can create closure problems that may interrupt the slab design.
Proper alignment can only be achieved by proper adjustment of each deck panel as it is placed. Cover width errors accumulated across the bay cannot be corrected with the last sheets in the run. On-site experience has demonstrated that the frequency of snapping a chalk line determines the accuracy of rib and flute alignment. This minor effort at the time of deck placement elimi- nates the need for field corrections.
For deck to perform its design functions and serve as a working platform, it must be adequately and properly attached. Often the deck is used as part of the horizontal bracing system and the fas- tening method and pattern have been selected to provide a certain strength and stiffness in the plane of the deck.
Deck fastening to the structural frame can be accomplished with welds, self drilling screws, air driven, or powder driven fasten- ers. For deck that is intended to end lap roof deck , the end lap location should be adjusted so the center of the lapped portion occurs over the support or, when supported by bar joists, over a top chord member.
Only qualified operators may use powder actuated tools; air actuated tools must be used by trained operators familiar with all safety procedures. These screw guns are equipped with a clutch and depth limiting nosepiece to prevent over torquing.
Air driven tools are operated at a pre-set pressure level consis- tent with the fastening requirements of the deck attachment. Air is supplied by a compressor equipped with a regulator that prevents over-driving or under-driving the fastener.
The fasteners have a flat head at the drive end and a ballistic point at the penetrating end. A variety of sizes are available to meet the penetration requirements of the steel substrate. Quality welding of light gage deck requires experience and the selection of proper amperage and electrodes.
A weld quality control test procedure is shown in Figure 7. Weld washers are not recommended for deck thicknesses of 0. Weld washers are recommended for metal thicknesses less than 0. Proper welding requires good metal to metal contact; therefore, lapping composite deck units with shear lugs is not rec- ommended.
For the same reason, built in hanger tabs in floor deck that bear on structural steel should be flattened or removed. The opposite end of the panel can then be rotated, which places the welds in shear. Separation leaving no apparent external weld perimeter distresses, but occurring at the sheet-to-structure plane; may indi- cate insufficient welding time and poor fusion with the substrate. Failure around the external weld perimeter, showing distress within the panel but with the weld still attached to the substrate, would indicate a higher quality weld.
These studs are usually installed after the deck has been spread to act as a working platform. Therefore, it is necessary that the platform be adequately attached to the structure before the studs are installed. Shear studs can be welded through the double metal thick- ness of cellular deck. Note: If the deck is heavier than 16 gage the stud manufacturer should be consulted for installation procedures. Shear studs, like all other fasteners, must be installed in accordance with the design drawings.
Since most construction work is done in open air, ventilation for welding is usually adequate. However, for closed in areas, ventila- tion must be provided. Adequate ventilation is extremely important when welding galvanized deck. All workers involved in the welding operation must wear eye protection to avoid weld flash. Cutting and welding sparks can cause construction fires.
Conditions at a construction site are subject to rapid change. Weld- ing may be safe in a given area and then, because combustibles are introduced, the area is suddenly not safe. The General Contractor job supervisor should prevent other trades from storing combustibles near or under areas where welding is to be done.
Constant alertness in and below the general area is mandatory. These are frequently referred to as stitch connections. Self drilling screws, welds or button punches are the usual stitch con- nections. The installer must be sure that the underly- ing sheet is drawn tightly against the top sheet. Again, as when screws are used as the frame attachment, the special screw driving guns are used to prevent over torquing. Manual button punching of side laps requires a special crimping tool. Button punching requires the worker to adjust his weight so the top of the deck stays level across the joint.
Since the quality of the button punch attachment depends on the strength and care of the tool operator, it is important that a consistent method be developed. Automatic power driven crimping devices are rarely seen on deck jobs but should not be ruled out as a fastening method. Good metal to metal contact is necessary for good side lap welds.
Burn holes are the rule rather than the exception and an inspector should not be surprised to see them in the deck. The weld develops its strength by holding around the perimeter. On occa- sion, side lap welds will be specified for deck that has the button punchable side lap arrangement see Figure 8 for comments on this subject; see Figures 8 and 9 for welding these deck units to the frame. Welding side laps is not recommended for decks type 22 0.
Weld washers should never be used at side laps between supports. Just as when welding to the frame, adequate ventilation must be available and welding near combustibles prohibited. Loose tools should not be left lying about. Stud welding ferrules should be broken off of the studs. All debris must be removed from floor deck before concrete is poured. All parties concerned with the construction process should cooper ate to properly store combustible material and remove trash that can be a fire hazard.
Absolutely no loose deck sheets should be left at the end of the working day. Any partially used bundles must be tightly secured to prevent blow off. Usually the design professional knows the general area where a vent stack may cut the roof, or approximately where a telephone conduit may pierce the slab; but he may not know how big the hole will be.
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