Electrical installation construction of a Buddhist building in Jiangsu programme
2.1 Project Introduction * * * Building is the main building of the third phase project of * * * Scenic Area. It is located at the east side of the first and second phases of the project where the Buddha is located, at the foot of Qinglong Mountain, with Buddhism as the theme, and at the north end of the landscape axis of the third phase project*** The building has one underground floor and four floors on the ground. The building is 150 meters wide and 180 meters deep. The total height of the building is 22 meters. It reaches the highest point locally (the height of the tower top is 61.8 meters). The building area on the ground is about 39609 square meters, and the total building area is 47488 square meters. In this project, our company mainly undertakes the tasks of water supply and drainage installation engineering, building electrical installation engineering, ventilation and air conditioning installation engineering in * * * building engineering. The construction scope of building electrical installation engineering includes the construction and installation of lighting system, lightning protection and grounding system, and power system. 2.2 Main physical quantities See Table 2.2-1 below for main physical quantities. Table 2.2-1 Main Physical Quantities No. Equipment Material Name Specification Model Unit Quantity Remarks 1 Dry type transformer SCB10-1600/10 sets 2 2 Dry type transformer SCB10-1250/10 sets 2 3 High voltage distribution counter 18 4 Low voltage distribution cabinet GCK set 26 5 Capacitance counter 8 6 Power distribution counter 258 7 EPS counter 5 8 Various types of lighting boxes 258 9 Bus duct 500A-1600A meters 910 10 Enclosed bus Line box 2500A m 20 11 plastic sprayed bridge, plastic sprayed trunking 150-800 m 11000 12 cable and branch cable 2.5-185 m 73980 13 various conductors 1.5-300 m 209800 14 various steel pipes φ 15 - φ 65 m 30000 15 various lamp sets 2200 16 grounding bus - 40 * 4 m 10000 hot-dip galvanized flat steel 2.3 Electrical engineering division The electrical discipline of the project is mainly divided into power transformation and distribution system Lighting system, lightning protection and grounding system. See Table 2.3-1 for details of each system. Table 2.3-1 Electrical Engineering Discipline Classification No. System Project Overview 1 Power Transformation and Distribution Power System * * * Power System: This project uses two 10KV high-voltage power supplies, including one 10KV hot standby power supply. The total capacity is 9200KVA. There are two substations in the basement, one is in the * * * basement and the other is in the * * * basement. There are five high-voltage outgoing lines, two are for * * * and * * *, and three are for Lingshan Phase I and Phase II original substations. There are two (10KV/0.4KV) 1250KVA transformers in * * *, and two (10KV/0.4KV) transformers in * * * The transformer with a capacity of 1600KVA, 18 high-voltage distribution cabinets, 26 low-voltage distribution cabinets, 8 capacitor compensation cabinets, 258 power distribution cabinets in the north and south areas, * * * and * * * ground floors 1-4 and underground floors 1-2 are respectively powered by corresponding substations, and the low-voltage power supply adopts the hybrid distribution mode of radial and trunk type. 5 sets of emergency power supply EPS machine rooms are set in the basement of the south area to ensure the power supply of fire protection for important loads, such as fire water pumps, smoke exhaust fans and other loads, which adopt the mode of dual power supply terminal self switching. 2 Lighting system ****** Lighting system: It is divided into general lighting, accident lighting and evacuation indicating lighting. In addition to mutual switching of dual power supply terminals, emergency lighting is also equipped with its own emergency power supply. Most of the lighting in public areas adopts centralized control mode. The lighting in general public areas is centrally controlled by BA. The lighting in the public areas of the gallery, tower and hall is centrally controlled by the light control system for dimming and dimming. The rest of the lighting is locally controlled. The stage lighting, lighting and sound in the * * theater are controlled by independent centralized systems. The lighting in the dome of the theater is controlled by LED lights, DMX512 control system is used, which takes DCS - 4000 as the leading controller, outputs standard DMX512/1990 signals to the lamps and controls the lamps to achieve light changes. It can make LED lamps change light effects for countless times. Outdoor floodlight lighting is centrally controlled indoors. An emergency power EPS machine room is set in the basement of the south area to ensure the fire lighting load, Power supply reliability for normal operation of other important equipment such as fire center power supply and stage lighting during hot standby power switching. There are 328 lighting boxes in total. 3 Lightning protection and grounding ****** Lightning protection and grounding system: this project is a Class II lightning protection building. Concealed lightning strip (40 × 4 hot-dip galvanized flat steel) is set on the roof and parapet as the lightning arrester, and a lightning protection grid of 10m × 10m × 8m is formed on the roof; The two main reinforcements in the column are used as lightning protection downlead, and the two main reinforcements in the column are ¢> 16mm. The reinforcements in each ring beam and floor slab are used as side lightning protection devices and equipotential grounding devices. The two main reinforcements in the ring beam and the reinforcement near the column in the floor slab (¢≥ 16mm) are welded with the two main reinforcements in the column as lightning protection downlead, The bottom of the two diagonal main reinforcement in the column is welded with the ring grounding connection line, and the reinforcement of the foundation inner bottom plate is used as the joint lightning protection grounding device. 100 × 100 × 6 galvanized steel plate is embedded at the top of the column and welded with the metal tower. The metal roof is reliably welded with steel plate, and is protected against direct lightning, side lightning, and lightning electromagnetic pulse. The lightning arrester and lightning protection grid are connected with the downlead. The concealed lightning strip on the roof is safe and reliable, and all metal components on the roof are reliably connected with the concealed lightning grid. All grounding leads in the building are 40 × 4 hot-dip galvanized flat steel radially led out from the combined grounding body to each embedded point, and reliably grounded with electrical equipment and metal pipes. There are 8 lightning protection grounding test points, and the grounding test resistance is 0.5 Ω. (The design and specification requirements shall not be greater than 1 Ω) 2.4 Project characteristics, key points and difficulties * * * Building electrical installation works are characterized by more cooperation with civil engineering units and decoration units and tight construction period. Four typical characteristics are summarized, and then the key and difficult points are analyzed, and corresponding measures are summarized. See Table 2.4-1 for details. Table 2.4-1 Project Characteristics, Key Points and Difficulties, Key Points and Difficulties, Key Points and Difficulties Solution Measures, Large quantities of reserved and embedded works, difficult construction management, professional management personnel; Increase the authority of management personnel in the project organization; Strengthen the implementation of management system. A full-time person shall be assigned to take charge of the heavy workload of finished product protection, establish a finished product protection system, and implement the protection system; After the reservation and embedment are completed, the concealed acceptance work and data shall be done in a timely manner; Pay attention to the weather forecast, and strengthen the protection of finished products before rainstorm. The process coordination work is complex. Do a good job of deepening work before construction, and foresee problems early; Construction conflicts among disciplines shall be solved through coordination meeting; Pay close attention to the construction progress of civil engineering and synchronize the processes; Timely propose written plans for the cooperation needs of other professional contractors. There are many types of bus systems, many systems, many narrow spaces, and there are electrical, weak current, fire protection, air conditioning, decoration and other systems. Through pipeline balance, deepen the design, make rational use of space, determine the location of each system, and organize the construction sequence. The number of complex cables in the electrical cable system is large, and the number of pre branch cables is large. The detailed design layout of bridge and cable shall be prepared in advance; Determine the cable tray and cable laying sequence; Lighting and communication meet construction requirements; Hole protection, safe operation of machines and tools, reasonable organization of human and material resources, and various measures to ensure orderly cable laying. The complex commissioning workload of the power supply system is large. According to the design and construction, increase the input of the commissioning force, and check the power supply and distribution system layer by layer to ensure that the commissioning work is completed in time.