One on the upper layer, one on the lower layer, reserved joints and then welded with the upper columns, beams to form an equalized pressure ring.
Grounding reinforcement is best not to be installed in the concrete foundation;
One is the grounding resistance is not easy to meet the requirements (humidity is not enough);
Two is struck by lightning when the strong current will destroy the foundation, along the foundation around the ground in the underground soil in the deep network is standardized; drawings without grounding requirements, should also be considered to grounding protection.
Expanded information:
Lightning protection and grounding devices include the following parts: lightning receiving device: directly or indirectly receive lightning metal rod. or indirectly receive lightning metal rod (flashover), such as lightning rods, lightning straps (net), overhead ground and lightning arrester. Grounding wire (lead wire): lightning receiving device and grounding device connected to the metal conductor.
Grounding device: the sum of grounding wire and grounding body. The grounding body refers to the descending resistor, flat steel and so on. And lightning protection and grounding device installation of this project lightning protection and grounding system also consists of several parts: the use of foundation base plate as a grounding electrode, outdoor ground minus one meter laying -40 × 4 of the ring equalizing belt, the use of structural steel to do the lightning lead, roof laying φ16 and -25 × 4 as a lightning belt. The grounding system requires a total grounding resistance of less than 1 ohm.
(1) material requirements galvanized flat steel, round steel, copper rows, etc. should be galvanized well, the material itself shall not have cracks, wrinkles, etc., a variety of profiles are all imported by the regular manufacturers and have a product certification and testing reports.
(2) construction process requirements galvanized flat steel, round steel connection are used welding, round steel double-sided welding requirements, welding length of not less than 6D, flat steel three-sided welding, welding length greater than two times the width of the flat steel, weld seam flat, full, no slag, bite phenomenon, the welded joints in the concrete structure outside the bitumen paint should be coated with two to avoid corrosion, the roof lightning belt should be coated with silver powder paint two. Copper rows are connected by two M8 galvanized screws, and the lap length is more than twice the width of the copper rows.
Baidu Encyclopedia - Lightning protection and grounding