Safety inspection of outdoor LED display columns
In addition to ensuring the quality of the screen, the column-type LED display has a very important place that must be considered, that is, the column of the LED display. The safety of the column of the outdoor LED display can be inspected from the following three aspects. :
Inspection of the base of the LED display column.
There are two main types of base forms and layouts:
1. One is the balanced gravity type, that is, the upper load is mainly balanced by the gravity of the large-volume foundation, generally a concrete foundation. This base form is suitable for use when the soil is soft and there is an open construction site.
2. The other is the pile foundation type, in which reaming piles are the main type. This type of foundation method can be selected under the condition that the construction site is limited. When judging the base of the advertising screen, the initial drawings and construction materials must be checked first, and then the base must be excavated when the conditions permit, to find out whether the base method, depth, size, etc. are consistent with the drawings, and the The strength of the LED screen base concrete is sampled and tested. In other on-site investigations, regarding the selection of advertising screens with balanced gravity foundations, special attention must be paid to whether there are foundation soil bulges and loosening around the roots of the steel columns, and soil formation after the foundation is shaken under the action of wind load. If the surface is concave, it means that the anti-overturning resistance of the base can no longer meet the requirements, and there is a danger of collapse at any time under the action of strong wind, and it must be reinforced immediately. Under normal circumstances, this kind of situation is less likely to occur with deep pile-based advertising screens.
Check the material of the column.
1. Check the quality of the connection between the steel column and the foundation.
The advertising screen steel pipe column and the foundation are generally bolted or welded. If bolted connection is used, it is necessary to check whether there are missing bolts during inspection, and the bolts must not be damaged such as deformation, slippage and loosening; if there are design drawings, the specifications and models of the bolts must meet the design requirements; the bolts should be rust-proof. If the rust is serious, it must be replaced immediately, and the bolts should be fastened firmly and reliably; for high-strength bolts, the exposed threads should be 2 to 3 threads, and 10% of the bolt threads are allowed to expose 1 or 4 threads; The depth must meet the requirements of the specification.
2. Inspection of steel columns.
First of all, it is necessary to measure the skew amount of the advertising screen steel column. The skew amount of the steel column cannot be greater than 1000/H. It must be measured in two directions; the second is to check the steel quality of the advertising screen steel column. The appearance quality inspection of the steel can be divided into For uniformity, are there any items such as interlayers, cracks, non-metallic doping and significant segregation. When there is doubt about the quality of the steel, samples can be taken from the components to test the mechanical properties of the steel and analyze the chemical composition, but the safety of the structural components should be ensured. Finally, it is necessary to check whether there is corrosion of the steel pipe column and the quality of the protective coating of the steel structure. The quality of protective coatings for steel structures should be tested according to the current relevant national product standards for the quality of coatings.
Inspection of the upper steel frame member system.
At present, there are two forms of connection between the steel column and the upper steel frame member system:
1. One is T-shaped, and its main frame is made of steel columns and a horizontal main beam on the upper part in a T-shaped connection. The advertising screen is connected to the T-shaped rigid frame structure through various pendants and diagonal braces.
2. The other is the space truss type. The main skeleton is welded by an independent steel column and the upper horizontal main beams parallel to each other. The main beams are connected by horizontal and oblique supports to form a space truss system. The advertising screen is directly installed on the main frame.
Due to the top-heavyness of the column of the outdoor LED display, there will be more or less safety hazards after a period of use. The main structure of the LED advertising screen must be regularly inspected and maintained to ensure safety.