Safety Analysis On Unloading Platform Of High-rise Building Under Unfavorable Conditions

After 40 years of reform and opening up,China has made remarkable progress in all aspects,especially the construction industry has achieved a qualitative leap.With the increase of urban population,the status of high-rise buildings is particularly important.As an indispensable unloading platform in the construction of high-rise buildings,the safety management issues have received more and more attention.Nowadays,the specifications and technical requirements of the unloading platform are not perfect,resulting in a number of security vulnerabilities in the entire workflow of the design,production,installation,use and disassembly of the unloading platform.These potential risk factors may cause the platform collapse,certain casualties and economic losses.So the unloading platform is important safety hazards on the construction site.Therefore,it is of great significance to improve the safety standards and optimize the design of the unloading platform.This paper firstly expounds the research status of unloading platforms at home and abroad through the literature research method.It is found that the mature technology and management experience abroad is worth learning.The domestic research on the unloading platform is mainly prominent in the safety management,and the technical level.The innovation research is slightly behind.Secondly,the design requirements of the unloading platform and the design of the main connection points are introduced in detail.At the same time,the calculation method of the unloading platform is expounded,and an engineering example is used to verify that the calculation result of this method can meet the requirements of the specification.In this paper,the ANSYS finite element software is used to establish the model of the above case,and the displacement and stress changes of the primary and secondary beams of the unloading platform under five different working conditions are analyzed,Summarizing the following conclusions:(1)When the first wire rope is lost,the safety rope can ensure the normal use of the platform;(2)The unloading platform without wire rope pulling is strictly prohibited from appearing on the construction site;(3)The steel beam under the platform plate is the result of simulation analysis of the two-span discharge platform.Although the requirements of the specification are met,the environment in the site is complicated and there are many unforeseen factors.Therefore,it is not recommended for the construction unit;(4)When considering the downward wind load,the simulation results are significantly 50% higher than under normal use conditions.The greater the wind load,the greater the stress and displacement of the primary andsecondary beams of the platform.Therefore,when encountering windy weather of six or more levels,the stress and displacement of the unloading platform will become larger.At this time,the operation of the platform should be prohibited.Finally,the three types of accidents that often occur in the unloading platform are analyzed,and the corresponding accident tree model is established to summarize the causes of the accidents.At the same time,the problems that may occur in the whole life cycle of the unloading platform are pointed out and corresponding solutions are proposed.Preventive measures,we hope to fundamentally curb the occurrence of accidents and improve production efficiency.