The construction process of the open-web joist equipment steel structure is a progression from the bottom up, involving the gradual shaping and transition from incomplete to complete structures. Throughout the process, there are changes in structural shapes, with different stages featuring varying structural forms and load-bearing characteristics. Consequently, the internal and external load conditions at each construction stage are not uniform. It is crucial and significant for the quality level of the construction materials products used in the open-web joists to enhance their utility, as it plays an essential role and impact on the execution of construction activities, which is also vital and important to customers.

When placing the开口floor deck on steel beams, always ensure stability. It is difficult to vertically hoist the floor deck through the narrow space between the secondary beams due to the arc area, and it disrupts the normal welding process of the secondary beams. When hoisting, use soft hoisting ropes, and check the condition of the ropes before each operation for any cuts or tears; replace them immediately if found.

1. Initially, the centerline of the steel beam is popped out in the deck area, which serves as the control line for the placement of the composite deck. The centerline of the main beam governs the overlap width of the steel beam with the composite deck and determines the welding points for the full penetration welds between the deck and the beam. The centerline of the secondary beam determines the welding position of the full penetration rivets. Since it's difficult to observe the exact position of the secondary beam flanges after the composite deck is laid, the centerline and width of the secondary beam flanges are反弹 onto the main beam's centerline. When fixing the rivets, the centerline and width of the secondary beam flanges are反弹 back onto the composite deck on the secondary beam face.

2. The connection between the deck panels and side panels is chosen to be clamped with a clamp, which joins the individual deck panels into a solid sheet. First, spot-weld the side edges of the deck panels, then secure both ends, and later, use bolts for fixation.

3. The floor slabs are sorted and sectioned at the material storage area according to the material list, numbered clearly, distinguishing between layers, sections, and numbers with a marker pen, and accurately transported to the designated construction locations.

4. During hoisting, use soft slings to ensure that the composite floor panels maintain their overall integrity without deformation and without curling at the edges. For multi-story steel structure designs, the general practice is to install columns in sections of three layers per section (needless to say for single-story). When installing composite floor panels, the work should be synchronized with the steel column and beam construction, with at least a three-story difference. Therefore, during the hoisting of composite floor panels, they can only be passed through the beam-column spaces of the upper level, and the crane operator should control the lifting layer by layer between the beams and columns.

5. Edge cutting should be performed using a plasma cutting machine or shearing press, with excess material kept within a 5mm range during cutting. Measures should be taken during concrete pouring to prevent leakage.

6. Enhance concrete curing.

Open-web floor decks, during their use, serve merely as long-term formwork under cantilever conditions. The cantilever length can be determined based on the cross-sectional characteristics of the open-web floor deck. To prevent cracking of the cantilever plate, negative reinforcement should be installed at the supports according to the design of the structural engineer. When the open-web floor deck is placed on steel beams, it should prevent overhangs. Operators should wear safety belts during the laying process and ensure stability.

Edge laying is fixed to the surrounding stable ropes. Welding uses penetration spot welding connections. Before welding, prepare scrap material for arc trial welding and adjust the welding current.

Due to the absence of horizontal formwork and vertical supports at the bottom of the opening floor deck, the concrete pouring should not be too concentrated. A flat vibrator should be used promptly to evenly distribute the vibration. The product is widely used in power plants, power equipment companies, car showrooms, steel structure factories, and other construction projects.

Why Do Open-web Floor Decks Develop Cracks?

We must use open-web deck plates correctly; otherwise, issues may arise, with one common problem being cracking. Below, we'll introduce the various reasons why open-web deck plates may crack.

1. Uneven load-bearing on the opening floor slab can easily lead to cracking. Generally, buildings constructed in strict accordance with construction specifications should not experience such issues. If they do, it indicates problems during the work process, or the use of substandard or不合格 materials.

2. Uneven foundation settlement caused uneven settlement beneath the opening floor slabs, leading to cracks. As some concrete components and the interior and exterior walls developed cracks along the height of the building, it resulted in severely insufficient concrete strength and thickness, and led to disasters and accidents.

3. Non-stress cracks are a common type of non-stress crack, primarily caused by factors such as temperature, shrinkage and expansion, and construction processes.