Steel structure grid roof construction scheme

Installation of the skeleton (or purlin).

Depending on the skeleton material, the construction tools are different. There are roughly the following mechanical equipment: electric welding machine, grinding wheel cutting machine, profile cutting machine, angle grinder, pistol drill, switchboard, power cord, hose glue gun and small hardware tools.

The construction sequence of this project: component correction→ rust removal→ lofting number material→ blanking and forming→ installation and welding.

The roof purlins of this project are made of light steel such as steel square and C-shaped steel, because light steel often bends and warps during transportation and stacking, so after the material enters the site, it is first straightened and leveled, and the site uses a wrench bender or manual correction work.

Before removing rust from the skeleton material, dust and dirt should be removed from the surface of the steel. The rust removal of the steel components of this project adopts a combination of manual and electrical tools. After the rust removal work is completed, the anti-rust primer should be brushed or sprayed again.

According to the drawing size, the C-shaped steel (or square tong) is cut to the appropriate length with a grinding wheel cutting machine, and then the skeleton is welded. The welding process uses AC arc welding machine and E43 series, and in order to prevent defects such as meat bite and welding head, small current and small diameter electrode (2.5-3.0mm) are used for welding. And use auxiliary fixtures and fixtures to ensure the accuracy of the geometric dimensions of the structure.

The steel skeleton is tested and corrected with a level and the steel wire. The production process should be measured and corrected at any time, and the deformation should be controlled within the allowable range. The skeleton and the support pallet surface are welded together, and the skeleton production can assemble and weld a part of the skeleton, and then lift it to the support pallet for welding firmly, or it can be directly assembled and welded on the support pallet, and the skeleton in the same slope direction should be on one surface.

After the skeleton is made and installed, dust, iron filings, oil, etc. on the surface of the skeleton should be removed. According to the requirements of the drawing, brush the anti-rust paint, and then brush the topcoat and protective paint after the anti-rust paint is completely dry. For the metal skeleton of the roof, the coating generally adopts two methods: manual brushing and air spraying.

The coating work is carried out immediately following the grid installation and keel installation, the coating worker should be equipped with a thermometer and thickness tester, the topcoat is manually brushed on site, should not leak, the optimal temperature of construction should be 5-30 degrees, and the humidity is not higher than 85%. Do not brush on rainy days. Brushing should be divided into batches at intervals of 12 hours, and the brushing should not be too thick at one time to prevent flow marks. The ventilation environment should be good during construction, and attention should be paid to avoiding open flames. During the production of purlin skeletons, roof panels and perimeter enclosure materials should be prepared in time to avoid delaying the construction period.

Installation of roofing and enclosures

The roof mainly adopts 50mm thick sandwich panels, and the length of the roof panel depends on the engineering needs and transportation requirements. The installation adopts hidden buckle connection, the use of self-tapping nails fixed on the purlin, the installed profiled steel plate requires tight lap, the roof panel corrugation is guaranteed to be perpendicular to the ridge axis, and a straight line is pre-placed with a measuring instrument to determine the arrangement of the overall plate.

In large construction projects, in order to shorten the time, the bundled roof panels can be lifted directly from the truck to the roof frame by crane, and for longer slabs, the method of flat stretcher and hanging rope is recommended. For small and medium-sized projects, it can be unloaded by hand, and then a single roof panel can be tied with ropes, and then the roof panel is pulled to the roof frame by manpower, and then fixed and installed. This project adopts manual handling construction.

In order to protect the surface of the laminated steel plate on the roof panel and ensure the safety of the construction personnel, the laminated steel plate must be touched with dry and clean gloves. Do not drag the roof panel surface laminated steel plate on the rough surface or the roof panel laminated steel plate, and other things such as tools can not be dragged on the surface of the roof panel laminated steel plate.

When walking longitudinally along the roof panel, walk in its groove, and when walking laterally along the roof panel, try to get as close to or step on the roof support point as possible. In general, the load should be distributed evenly on the soles of the feet as much as possible, not concentrated on the heels or toes. Wear soft-soled flats, not strip-notched sols, which tend to be embedded in small pebbles. The surface of the newly dismantled roof panel laminated steel plate is greasy. Be very careful when acting. It is inevitable to cut the surface laminated steel plate of the roof panel on the construction site, but care should be taken to protect other plates, because the chainsaw cutting will produce metal particles. If it must be cut on other roof surface laminated steel plates, a protective object should be placed between the cut roof surface laminated steel plate and the lower roof panel surface laminated steel plate, and the roof panel surface laminated steel plate should be face down, and it is best to put a metal cutting knife in the chainsaw. Compared to emery wheel cutting, this results in fewer metal particles and a smoother cutout.

In general roofing and flashing board installation operations, self-tapping bolts, drilling, hand saws, chainsaws, or other operations will leave metal debris in the adjacent areas of the roof, and these debris and other debris (rivets, iron nails, screws, etc.) must be eliminated from the roof, flashing board, gutter, etc. as soon as possible. Make this work the end of the day. Especially after the installation of the entire roof, it cannot be exempted. Neglecting this work will oxidize the metal debris and cause the surface to form a stain. When iron, copper, lead, etc. as the base material of the article and the surface of the aluminum-zinc plated sheet are in contact with the surface of the galvanized sheet, and are jointly exposed to moisture or condensation, it will cause the damage of the aluminum-zinc layer and lead to corrosion of the steel plate from the surface.

When lifting the roof surface laminate steel plate to

the level ready to start the installation, please pay attention to ensure that all the roof surface laminate steel plate is facing up and all lap edges are facing the roof side to be installed. Otherwise, not only will the roof panel surface laminate steel plate be flipped, but also the roof panel surface laminated steel plate will turn around. Bales of laminated steel panels on the roof panel shall be placed close to or placed on the purlin support point, not in the purlin span, and before fixing the first plate, ensure that its position is vertical and square, and that it falls correctly in relation to other building elements.

When the first roof panel surface laminated steel plate is

fixed in place, a continuous collimator is pulled at the lower end of the roof, and this line and the first roof panel surface laminated steel plate will become the conductor, which is convenient for the rapid installation and correction of subsequent roof panel surface laminated steel plates. Then, each roof area is to be tested in a fixed section during installation, by measuring the width of the laminated steel plate on the surface of the fixed roofing panel, once at its top and once at the bottom, to ensure that there is no movement and fan. At certain stages, such as halfway through installation, the distance from the top and bottom of the fixed roof surface laminate steel plate to the far edge of the roof or the finish line is also measured to ensure that the fixed roof surface laminated steel plate is parallel to the finish line. If adjustments are required, each plate can be placed and fixed later for slight sector adjustment. Until the roof surface laminate steel plate reaches flatness. According to the construction drawings, the grid roof panels are stacked on the material stacking yard in a complete set, and the complete sets of grid roof panels are hoisted to the design position and fixed with the crane.

The

connection of color steel plate and steel structure purlins should use bolts or self-tapping screws. When using bolts, a larger piece should be used, and the tightening force should be moderate and firm to avoid pitfalls in the connection fastening point. The bolts of the wall should be neat. Symmetrical, evenly spaced. The color steel plate used for the corner, that is, the corner plate should be marked in detail on the construction drawing, and the construction should be carried out according to the drawing. The inner outer corner of the corner plate should use color steel corner plate or angle aluminum, and its butt joint should be flat and dense, and the wall surface of the color steel plate should be kept smooth and vertical. The connections at the corners of the corner plates should be neat and consistent. Level. The vertical direction should be in a straight line, there should be no obvious depression at the connection without obvious misalignment, and no wavy warpage should occur after the inner outer corner edge is connected. During installation and construction, in addition to complying with the relevant technical requirements of roof waterproofing engineering, the roof waterproofing project should also comply with the following principles:

1) The slope of the roof shall not be less than 5%, and the corrosion environment shall not be less than 8%.

2) The roof panels shall not be overlapped when conditions permit. When lapping is necessary, it should be lapped in the long direction of the slope, and the lap point must fall on the purlin or support. When the roof slope is less than or equal to 10%, the lap length is not less than 250mm, and when the roof slope is greater than 10%, the lap length should not be less than 180mm. The lap steel plate part should be connected with stitching nails or pull rivets, and the middle distance should not be greater than 300mm. All lap joints must be sealed with sealing paste or waterproof material, and exposed nail heads should be waterproof. Where the roof panels that must be lapped in the long direction of the slope, the concealed buckle pattern plate is the first to push. Use self-tapping nails to fix the special fixation seat of the dark gusset plate on the purlin, and then lay the dark gusset plate on the special support, and clamp the lap part with a special fixture at the crest of the plate, and the plate is fixed as a whole. During the construction process, pull rivets or self-tapping nails can not be punched at the valley to avoid roof water seepage or leakage, the lateral lap of the roof panel (corrugated type) should be consistent with the dominant direction, and the lap part must be set with waterproof sealing material.

Wrapped corner watercolor steel plate. The lap of the eaves dripping watercolor steel plate and other accessories should be crimped in the leeward direction or along the water direction as much as possible, and the crimping length should not be less than 60mm, which can be connected with pull rivets, and its spacing should not be greater than 200mm, and the side seam should be straight when installing. The roof panel should avoid opening holes as much as possible, and when holes must be opened, they should be in accordance with the design requirements and do corresponding technical treatment.

Maintenance and repair of glass roofing

1. Maintenance

(1) After the acceptance and delivery of the glass roofing project, the user unit should formulate the maintenance and repair plan and system of the roof in time.

(2) The maintenance of the roof should be carried out in accordance with the following requirements.

a. According to the roof area and the degree of ash pollution, determine the number and cycle of cleaning the roof, which should be every year

Wash at least once.

b. The mechanical equipment for cleaning the roof (such as the washing machine) should be flexible and convenient to operate so as not to scratch the roof

Glass.

2. Maintenance

(1) If the metal skeleton finds that the bolt is loose, it should be tightened or welded firmly. When rust is found to be on the connectors, it should be removed and repainted.

(2) If the glass is found to be loose or damaged, it should be repaired or replaced in time.

(3) When the sealant and sealing strip are found to be falling off or damaged, they should be repaired and replaced in time.

(4) When it is found that the anchorage of the main skeleton structure is loose or falling off, it should be replaced or taken measures to strengthen and repair it in time.

(5) Regularly check the drainage system and dredge it in time if blockages are found.

(6) When the glass roof is in normal use, a comprehensive inspection should be carried out every 5 years.

Roof enclosure

The following safety regulations should be met in the maintenance and repair of roofs:

a. Inspection, maintenance and repair shall not be carried out in wind power above grade 4 and heavy rain.

b. The machinery used for cleaning and maintenance must be firm, easy to operate, safe and reliable.

c. In the maintenance and repair work, all those who work at height must comply with the relevant provisions of the current national standard "Safety Technical Code for Work at Height in Building Construction" (JGJ80).