Due to market reasons, LED display steel structure installation accidents and violations occur from time to time, causing unnecessary economic losses and social impacts. In order to further improve the overall level of steel structure construction and promote the development of the industry, in addition to strengthening construction site management, steel structure construction should also conduct research and summary in construction organization design, schemes, technical measures, etc.; vigorously promote new technologies and processes; target engineering Features, choose an advanced, reliable and economical construction plan.
led display
The basic principles of the steel structure hoisting plan for the led display
Policy-based on drawings, norms as guidelines, strict implementation of relevant safety production regulations.
Reliability-Adhere to safety, ensure the feasibility of the implementation of the plan, and increase its reliability. No matter which method is adopted, we must first consider whether the program has a successful precedent and supporting equipment, otherwise the program must be demonstrated. According to the characteristics of the structure, the construction check is carried out to prove whether the stability of the structure and the stress and deformation of the rods meet the requirements during the construction phase of the method. Whether the mechanical equipment used can meet the installation requirements. Whether the construction site conditions are met, such as whether the civil construction environment and surrounding structures restrict the implementation of the plan, etc.
Advancedness——With the development of science and technology, new processes, new technologies, and new equipment in the field of structural installation are emerging in an endless stream. For example, the advent of large-tonnage cranes, and computer-synchronized control of overall lifting and sliding technology have added a new chapter to structural installation. Especially for large-scale steel structure projects, when the site conditions and structural forms permit, new technologies and new processes should be vigorously promoted; the amount of high-altitude work should be reduced as much as possible, and the installation efficiency of steel structures should be continuously improved.
Economy-a good installation plan should be simple in method, appropriate measures, high in efficiency, low in construction cost, wide in application range, and able to withstand review and test. Therefore, we must adhere to the principle of program comparison, conduct technical and economic analysis, and choose a program with a short construction period and low cost.
Applicable conditions for the steel structure hoisting plan of the led display
Due to the inconsistency of architectural modeling and structural form, the construction site conditions vary greatly. It can be said that no construction method or scheme is suitable for the installation of any steel structure project, so each installation method has its own supporting conditions.
The commonly used installation methods of grid structure are: high-altitude bulk method, strip and block installation method, structure slip method, support frame slip method, integral hoisting method, integral lifting method, etc.
Considering according to the process method: understand the characteristics of structure form, structure weight, installation height, span, etc., and choose mature and advanced installation technology as far as possible in combination with the actual situation of the site.
According to the consideration of lifting equipment: first select own equipment, make full use of on-site lifting equipment, and secondly rent it nearby. General situation: when the number of components is small, truck cranes are often used; gantry frame hoisting is mostly small and medium-sized truck cranes; when the installation period is longer, the installation height and the turning radius are large, crawler cranes are more economical than truck cranes; overall Hoisting and sliding mostly use hydraulic synchronous lifting (incrementing) devices; middle and high-rise steel structure installations generally use tower cranes; ordinary bridge installations mostly use gantry cranes and bridge erecting machines.
Inverted installation method-Inverted installation method is a special installation process of up and down. It is suitable for structures with large height-to-width ratios, such as steel towers, masts and other structures. When it is difficult for conventional cranes to approach the hoisting, the upside-down method is generally used. When adopting this method, it is necessary to focus on the overall stability of the structure during the installation process and the stability of the equipment itself, and reliable support and stability measures must be taken. Structure slip method-The structure slip method has been developed to adopt hydraulic pusher and computer synchronous control technology, which is a step more advanced than the past grid slip method.
Its applicable conditions are: , due to site conditions, no crane and support frame can be installed in the span; second, the structural support conditions are conducive to laying sliding tracks; third, the strength and rigidity of the sliding unit structure determined by calculation All meet the requirements; fourth, understand the form of structural support and fixing methods; fifth, the longer the longitudinal slip path, the higher the efficiency. Support frame sliding method-its applicable conditions are the occupation of the inner space, the lower installation height, the larger structural area or the longer longitudinal length. When the installation height is less than 15 meters, you can choose ordinary fastener-type steel pipe scaffolding or bowl-type scaffolding as the support frame; second, for the higher frame body and the load-bearing capacity, the steel support frame should be used. No matter which scheme is adopted, in addition to the requirements of the code, the horizontal dynamic load must be considered in the design calculation, and large diagonal braces should be added when necessary to improve its overall stability.
Overall lifting method-The overall lifting method currently mostly uses computer synchronous control and hydraulic lifting equipment developed by Tongji University. This process has gradually replaced the through-core motorized lifting and jack lifting schemes. The equipment is portable and the technology is advanced. Its applicable conditions are: , occupies the space within the span; second, the installation height is higher; third, the components are heavier; fourth, it is limited to vertical hoisting and cannot be moved horizontally. That is, the higher the installation height, the heavier the lifting weight and the better the effect.
Aboriginal hoisting-Indigenous hoisting is the use of single-angle bar, herringbone, rolling yard machine, pulley block, etc. as lifting equipment for structural hoisting. It is suitable for projects with heavy components, small quantities, and high installation heights. As there are more and more large-tonnage lifting equipment and advanced installation technology, so the local method of hoisting is also less and less.
Rotation method construction-This method is mainly used for bridge installation. Due to the influence of railway, highway traffic, and mountains, rivers and ditches and other special environments, when other bridge erection methods are restricted, the rotation method is often used.
Integral hoisting method-it is basically similar to the overall hoisting method, except that the lifting equipment is different, and it is suitable for small and medium-sized structure installation. In the early days, several monopod poles or herringbone frames, hoists, pulley blocks and cable wind systems were used for large-tonnage hoisting. Now, due to the large number of large-tonnage cranes, multiple cranes are selected for centralized lifting and installation for small and medium-sized projects according to the needs.
