How to determine the reliability of outdoor LED display rental, mainly from the following three aspects:
First, to determine the basis of the column LED display rental.There are mainly two ways to settle it
1. One is the balanced gravity type, that is, the upper load is mainly balanced by the mass foundation gravity, usually the concrete foundation. This foundation method is suitable for soft soil and open construction site.
2. The other is pile foundation type, in which the reaming pile is the main one, which can be selected under the condition of limited construction site. When judging the advertising screen foundation, the first thing is to check its original drawings and construction materials, and then excavate the foundation if conditions permit, to find out whether the foundation method, buried depth, size and other conditions are consistent with the drawings, and to check the strength of the advertising LED screen foundation concrete by sampling. In other field investigations, special attention should be paid to the selection of balanced gravity advertising screen foundation Whether there is foundation soil arching and loosening around the root of steel column, and whether there is concave collapse on the soil surface caused by the shaking of the root under the effect of wind load. If there is, it is clarified that the anti overturning of the root can not meet the requirements, and there is a risk of collapse under the effect of wind at any time, so reinforcement treatment should be carried out immediately. Usually, the deep pile advertising screen is less.
Second, check and judge the raw materials of the column.
1. Check the connection quality between steel column and foundation.
The steel pipe column of advertisement screen is usually connected or welded with the foundation by bolts. If the bolts are used for connection, it is necessary to check whether there are missing bolts, and the bolts shall not be damaged by deformation, sliding and loosening; if there are planning drawings, the specifications and types of bolts shall meet the planning requirements; the bolts shall be treated with anti rust treatment, and if the corrosion is serious, they shall be replaced immediately, and the bolts shall be firm and reliable; For high-strength bolts, the exposed thread should be 2-3 threads, and 10% of the bolt threads should be exposed by 1 or 4 threads; the embedded depth of the bolts should meet the requirements of the specification.
2. Check the steel column.
Firstly, the skewness of the steel column of the advertising screen should be measured, and the skewness of the steel column should not be greater than 1000 / h, and it should be measured in two directions; secondly, the amount of steel raw materials for the steel tube column of the advertising screen should be checked, and the appearance quality of the steel can be divided into uniformity, whether there are interlayer, crack, non-metallic impurity and obvious segregation, etc. When there is doubt about the amount of steel raw materials, the samples can be taken from the components to check 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 the steel pipe column is corroded and the quality of protective coating for steel structure. The quality of protective coatings for steel structures should be checked according to the current relevant national commodity specifications.
Third, check the upper steel frame member system.
At present, there are two ways to connect the steel column and the upper steel frame member system
1. One is T-shaped, the main frame is made of steel column and upper transverse main beam in T-shaped fixed connection, and the advertising screen is connected with T-shaped rigid frame structure through various hangers and diagonal braces.
2. The other is space truss type. The main frame is welded by an independent steel column and several parallel transverse main beams. The main beams are supported and connected horizontally and obliquely to form a space truss system. The advertising screen is directly installed on the main frame.
Therefore, the outdoor column LED display rental used for a period of time, there will be more or less some security risks, which requires us to regularly check and protect the main structure of the advertising screen, and do a good job in rust prevention and other treatment of steel components, so as to ensure the reliability of column LED display rental quality and safety.
How to identify the stability of outdoor column LED display
