Due to the steel truss steel deck significantly reducing on-site steel bar binding work, accelerating construction progress, and enhancing construction safety guarantees, it has a very wide application in factory and civil housing construction. To ensure construction safety, we need to carry out construction correctly in the following order and methods. Let's take a look!

Steel Truss Steel Deck Installation Sequence

1)Construction sequence

A. Plan construction sequence: The laying of each floor's steel truss steel deck should preferably be done starting from the construction drawing's initial position in one direction, and the edge and corner parts should be handled last;

B. Elevation construction sequence: The steel truss steel deck of each corresponding floor should be laid following the construction sequence of the main structure installation.

(2) The installation of steel truss steel decks is suitable to be carried out after the installation of the next section's steel columns and supporting steel beams.

(3) Before laying the floor slab, the reference line for the starting position during installation should be set according to the layout shown in the drawings. Align the reference line to install the first panel, and then install the other panels sequentially. The floor slab connection adopts a locking method, and the pull hooks between the panels should be tight to ensure no leakage of concrete during casting.

(4) After the steel truss steel deck is positioned, its vertical steel bars at the ends and the bottom formwork should be spot-welded firmly to the steel beams. Along the width direction of the panel, spot-weld the bottom formwork to the steel beams using manual arc welding, with a spacing not exceeding 300 mm.

Vertical support reinforcement is welded to the steel beam

(5) After laying a certain area, the bottom reinforcement of the panels must be tied in place in a timely manner to prevent the lateral instability of the steel bar trusses. At the same time, temporary supports must be installed in accordance with the design requirements in a timely manner, and it must be ensured that the supports are stable and reliable.

(6) There must be no gaps at the panel ends and the overlap between the panel edges and beams.

(7) Additional reinforcement work and pipeline laying.

A. After laying a certain area, the connection reinforcement for the floor panel supports, reinforcement bars, and negative reinforcement bars, etc., should be installed in accordance with the design requirements.

B. At the openings in the floor slab, reinforcing bars should be installed at the edges of the openings as required by the design, and edge formwork should be installed around the perimeter. The reinforcing bars and bottom formwork of the steel truss floor slab can only be cut after the floor slab concrete has reached the design strength.

C. For pipelines laid in the slab, rigid pipelines should be used for straight-through installations, and materials with better flexibility are recommended for diagonal installations.

Stud welding

(8) Stud welding

The gap between the bottom form of the steel truss steel deckand the base material should be controlled within 1.0mm to ensure good quality of stud welding.

(9) Side formwork installation

During installation, the side formwork should be tightly attached to the steel beam surface. Every 300mm, spot weld welds of 25mm length and 2mm height between the side formwork and the steel beam surface. After installation, a comprehensive inspection must be conducted to ensure all side forms are installed according to the construction drawings, guaranteeing no presence of leakage points.

Install the side tempanel

(10) Installation Acceptance

The content of installation acceptance inspection includes:

A. The model of steel truss steel deckin each part;

B. Whether the vertical bars of the supports and the edges of the panel are welded to the steel beams;

C. Steel bar length and arrangement spacing;

D. Inspection of anchor bolt welding quality, quantity, and spacing;

E. Potential for leakage of grout at the panel edges;

F. Connection between steel truss steel deck and shear wall;

G. Temporary support conditions.

Steel truss steel deck installation method

(1)Before laying the steel truss steel deck panels, place the reference lines at the starting positions as shown in the drawings. Align the reference lines and install the first panel, then spot-weld its bearing vertical bars to the steel girders. Install the remaining panels sequentially. During the laying process, check the dimensions according to the marked sizes on the drawings for each span and make timely adjustments if there are deviations.

(2) The floor slabs are connected by a snap-fit method. The hooks between the slabs should be tightly connected to ensure that there is no leakage of grout when pouring concrete. At the same time, pay attention to the consistent direction of the slab arrangement. The truss node spacing is 200 mm. Pay attention to the alignment of the transverse nodes of different templates.

(3) At the corners of steel columns, the corners of core tubes, the beam surface padding connecting panels and other places where the planar shape changes, the two ends of the panel can be cut. Before cutting, the dimensions to be cut should be marked out and checked. After cutting, the ends of the panel still need to be welded with horizontal support bars and vertical support bars according to the original requirements. If the panel is cut in the middle of the node, the web bars also need to be welded to the vertical bars. Installation can only be carried out after the panel is in place.

(4)If the panel width at the end of a span is less than 576mm, the panels can be cut along the length of the steel bar truss. After cutting, there should be one or two steel bar trusses on the panel, and the steel bar trusses must not be cut.

(5) The steel bar trusses should be parallel to the ends of the steel beams, with the bottom formwork overlapping on the steel beams not less than 30mm. Along the length direction, the galvanized steel panel is spot-welded to the steel beams using manual arc welding, with an interval of 300mm.

(6) The steel bar trusses should be perpendicular to the ends of the steel beams. The vertical reinforcement at the end of the panel should have a lap length on the steel beams of ≥5d and not less than 50mm, ensuring the galvanized bottom form work can lap onto the steel beams.

(7) After laying a certain area, the floor slab support connection bars, reinforcement bars, and negative reinforcement bars should be installed according to the design requirements.

(8) When installing the side form work, it should be aligned using a string line. After proper adjustment, one end of the steel bar is spot-welded to the rivets, and the other end is spot-welded to the side form work to secure it. The distance between the bottom of the side form work and the top flange of the steel beams is 300mm.

(9) If openings need to be made in the slab during construction, they should be reserved. Reinforcing bars should be installed around the openings as per design requirements, and side form work should be set up. The reinforcing bars of the steel bar truss form work and the bottom form work can only be cut after the slab concrete reaches the design strength. It is recommended to cut from bottom to top to prevent the bottom form work edge from detaching from the poured concrete. Cutting can be done by mechanical cutting or oxygen cutting.

(10) After the steel truss steel deck is installed, no reinforcing bars on the steel bar truss should be cut. If it is indeed necessary to cut the steel bar truss, it should be reconnected with steel bars of the same model and meet the design requirements for the lap length.

(11) After the steel truss steel deck is laid, the finished product should be protected to avoid human-caused damage, and it is forbidden to pile up debris.

Installation precautions for steel truss steel deck

Steel truss steel decks are a type of unsupported composite deck panel.The rebar trusses are processed and shaped in a back-end processing palnt. On-site construction requires first placing the steel truss steel deck in the correct position,then welding the rebar,followed by welding the anchor bolts,and finally placing the rebar trusses for binding.After inspection,concrete is poured.

So,how can the installation quality of steel truss steel decks and the safety of installation personnel be ensured?What are the main precautions?there are mainly the following precautions:

(1) It is strictly forbidden for personnel to walk under the construction floor where the rebar steel truss steel decks are being installed.

(2) When laying steel truss steel decking, it is necessary to lay it as soon as the packaging is removed, and it must be fixed by electric welding while laying. It is strictly forbidden to lay loose decking without fixing or to use truss steel decking for temporary laying. If the building has irregular sharp corners, pay attention to safety.

(3) It is strictly prohibited to walk on steel truss steel decks that are not fixed or not installed with temporary supports according to design requirements. It is strictly forbidden to step on the galvanized bottom form work steel panels while walking to prevent accidents.

(4) After the steel bar steel truss steel decks are laid, openings should be promptly sealed, guardrails should be installed, and clear markings should be made.

(5) Special attention should be paid to cleaning and inspecting the surrounding and underlying areas near hot cutting locations to prevent fire hazards. Effective fire extinguishing equipment must be provided, and dedicated personnel should conduct inspections.

Steel truss steel deck installation improper

Earlier, Zhonggou New Materials introduced the characteristics and advantages of steel truss steel deck panels. Then regarding the disadvantages, customers might ask, are there any leakage issues when using steel truss steel deck panels? The answer is yes, what specific factors will affect leakage? The details are as follows:

(1) Excessive spacing between supports, causing uneven stress, which in turn leads to deformation and leakage.

(2) If the T-type supports are not installed perpendicular to the ledges, it creates excessive gaps between the aluminum-magnesium-manganese roof panels, resulting in leakage.

(3) Workers on site are not proficient in operating the edge finishing machine, leading to improper finishing and subsequent leakage.

(4)The roof design has a large curvature, and the roof panels are not perpendicular to the secondary rafters, making the panel joints a weak point. This has a certain impact on the waterproofing quality.

(5)At the welding joint between the downspouts and the gutters, due to the stainless steel welding, there is significant deformation, causing local protrusions and water accumulation.

(6)The gutter installation is non-standard, with excessive segmentation, and the structural design along the length has no slope, resulting in a minimal slope for water flow and causing water accumulation.

Zhonggou New Materials mainly deals in a series of products and services such as steel truss steel decking, cellular decking and open-rid decking, green building and new building materials - steel structure composite steel deck for enclosure, and its brand ranks among the top three in China.