With the rapid development of technology and the arrival of the era of intelligent building, the strong current lines such as cables laid in cable trays, cables in metal pipes and enclosed bus ducts will cross the floor of high-rise buildings vertically. In addition, a large number of weak current lines laid in metal pipes will also vertically cross the floor of high-rise buildings. The setting of electrical room can be divided into two types.
In general, the clear distance of the depth of distribution room should be 1200 ~ 1500mm when laying vertical pipelines or installing equipment by carbon steel M10 wedge anchors on one wall and the clear distance of weak current room should be 1100 ~ 1400mm. The length of distribution room and the number of slotted hex head M8 mechanical anchors can be determined according to the number of electrical equipment and pipelines set in the electrical room.
According to the Code for Electrical Design of Civil Buildings, the size of the shaft should not only meet the size of wiring interval, terminal box, flat mushroom M8 toggle bolts and distribution box, but also leave a maintenance distance of no less than 0.8 m in front of the box. Although the operation and maintenance distance of the weak current equipment set in the weak current room is not specified in the "Code for Electrical Design of Civil Buildings", it should not be less than 0.8m.
After the pipeline and weak current equipment are fixed with flat mushroom heavy duty shield anchors, the opening size of the floor opening in the electrical room shall be provided to the structural specialty.
In general, the clear distance of the depth of distribution room is 600~800mm and the clear distance of weak current room is 500~700mm.
The number of access doors and carbon steel M10 drop-in anchors of the electrical room can be determined according to the number of electrical equipment and pipelines set in the electrical room. In order to prevent water from flowing into the electrical room, the access door of the electrical room shall be set with a threshold of 300 mm high.
The opening width of the floor opening in the distribution room is 300 mm and the opening width of the floor opening in the weak current room is 250 mm. To facilitate the use of zinc plated double expansion anchors to fix the formwork, the opening of the floor opening in the electrical room shall be 50mm away from the wall.
After the cable tray, enclosed bus duct and metal raceway laid vertically in the hole are fastened with carbon steel M8 stud anchors or other accessories, the reserved openings shall be sealed with inorganic fireproof materials layer by layer. The specific steps of a method for plugging the hole in an electrical room are as follows:
(1) Roughen all around the hole;
(2) Zinc plated lag screw shield anchors are used to fix the wood plate at the bottom of the hole;
(3) Pour 50mm concrete into the hole;
(4) Fill the hole with fire-proof cotton and the thickness of fire-proof cotton depends on the thickness of the floor.
(5) Concrete was poured in the upper part of the opening. After one day of concrete curing, the formwork can be removed and the thickness of the plugging material is the same as that of the floor. After the completion of the project construction, the property management department needs to increase the strong / weak current lines according to the change of house function. Steel pipe shall be reserved on the floor during cable wiring and fireproof plugging material shall be added after wiring.