The infrastructure of railway bridges includes many buildings and structures. They all need lightning protection. ZANDZ Technical Center recently received an application for the calculation of lightning protection of such buildings. Among them there are a station, a checkpoint, a police station, a garage and an aviary for service dogs. For each of the buildings, the ZANDZ Technical Center offered an individual solution for the protection against lightning. Let's study them in detail.
Solution
The calculations are made in accordance with the following documents:
- "Electrical Installation Code" EIC 7th ed. (hereinafter - EIC).
- "Instructions for the organization of lightning protection of buildings, structures and industrial communications" IS 153-34.21.122-2003 (hereinafter IS).
- "Instructions for lightning protection of buildings and structures" AD 34.21.122-87 (hereinafter - AD).
Protection of buildings from lightning strikes is carried out with the help of lightning rods. A lightning rod is a device rising above a facility that diverts lightning current into the ground without entering the facility. It consists of a lightning rod which directly takes the lightning discharge upon itself, a down conductor and a ground electrode.
External lightning protection of the railway passage objects
The set of measures to ensure the requirements for the lightning protection system of each of the buildings of the railway passage is represented by the following decisions:
- Installation of rod lightning rods is carried out. The heights and locations of the lightning rods are indicated on the drawings of each task.
- Down conductors are laid from lightning rods using copper bonded wire D = 8 mm, which are connected to an artificial ground electrode.
- The lightning rods are also interconnected to arrange two down conductors from each lightning rod.
- Fixation of down conductors (installation distance 0.6-1 m):
- on the roof slopes using clamps GL-11747A;
- on a flat roof – with the help of GL-11711 clamps;
- on the walls by means of GL-11703A clamps.
- Connection and branching of down conductors is carried out with the help of GL-11551A clamps.
Grounding of railway passage facilities
The set of measures to ensure the necessary requirements to the grounding device of each of the buildings of the railway passage is represented by the following solutions:
- Horizontal ground electrode is laid in accordance with the drawing of each building. The contour is made of corrosion-resistant copper-bonded stainless steel tape with the cross- section 4x30 mm, laying depth 0.5 m, distance to the wall of the building- at least 1 m.
- Installation of vertical electrodes with a length of 3 m (copper-plated steel pins with a diameter of 14 mm) in the places of the descent of down conductors
- Interconnection of horizontal electrodes is carried out by using clamp ZZ-005-064.
The arrangement of the elements of lightning protection system and the grounding device of the railway passage facilities is shown in Figures 1-5. The depicted protection zones correspond to the reliability of 0.9 of IS.
Figure 1 - Plan of lightning protection of the station
Figure 2 - Plan of lightning protection of the police station
Figure 3 - Plan of lightning protection of the checkpoint
Figure 4 - Plan of lightning protection for a garage for 11 cars
Figure 5 - Plan of lightning protection of the open aviary for service dogs
отверстие 150 на 150 – hole 150 to 150
Зона защиты на отм 3000 – protection zone at the mark of 3000
Сетчатое ограждение- mesh fencing
Accessories for lightning protection of the station
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Are you interested to know what materials are required for lightning protection of other buildings included into the infrastructure of a railway passage? Please contact our ZANDZ Technical center!