Research On Structural Selection And Performance Of Long SPAN Hangar

With the continuous enhancement of comprehensive national strength,the civil aviation industry is developing rapidly in China.Many large airports have been built and rebuilt in large and medium-sized cities all over the country,which lead the world both in scale and quantity.On the other hand,military airports are the important part of China’s national defense facilities and more and more money are spent on their supporting facilities.With the increasing of the fuselage,both civil and military aircraft put forward higher requirements for the function of hangar-better compatibility and durability.As a special long-span space structure,hangar is characterized by large span,large space and large opening.The structural selection of hangar depends on many factors,such as the change of aircraft type,the number of maintenance aircraft and airport clearance limit.On the premise of meeting the process requirements and ensuring the safe use,the main direction of aircraft hangar structural design is to consider the economic rationality of the structure in an overall,efficient and long-term way.The existing long-span hangars are almost constructed of steel structures.But in natural environment,steel structure is easy to rust.This is a fatal weakness in the development of steel structure for a long time.Especially in the southeast coastal areas,the main structure of the hangar is seriously corroded due to the severe impact of high temperature and humidity climate and sea wind erosion.Although some anti-corrosion measures have been taken,the effect is not ideal.Maintenance frequency and maintenance cost are high,and the normal use of hangar will be affected in the maintenance process.Aluminum alloy has many advantages such as light weight,high strength and corrosion resistance.Therefore,aluminum alloy space structure has been widely used in gymnasium and other buildings.But it is rarely used in hangar structure.This paper attempts to carry out a systematic study on the selection and performance of hangar structure and discusses the feasibility of using new aluminum alloy honeycomb composite latticed shell in hangar structure.Based on the summary of the equivalent theory of aluminum alloy honeycomb panel and the research results of plate and pole joint work by domestic and foreign scholars and combined with an example of a military airport hangar project,this paper puts forward that the light weight and high strength aluminum alloy honeycomb composite latticed shell structure system can be applied to the hangar structure.The wind resistance and seismic performance of the new hangar structure are also studied.The main contents and conclusions are as follows.(1)First,three kinds of honeycomb panel equivalent theory are adopted in static and dynamic finite element analysis of equivalent plates.The results are compared with the results of solid modeling and theoretical values.The results show that the three equivalent theories can be used when the accuracy requirement is not very high.When calculating the deflection under uniform load,the results of sandwich theory are close to the theoretical results.When calculating the natural frequency of the plate,honeycomb theory has higher accuracy.(2)Second,the complete coordination method,point contact method and hole coupling method are used to simulate the working state of plates and rods,which is compared with the experimental data.The results show that the load displacement curves of the three simulation methods are similar to those of the test data.Furthermore,the error between the finite element calculation results of the hole coupling model and the experimental data is the least.Point contact model is the second.The maximum shows in complete coordination model.The first two models need a lot of computation,so they are not suitable for practical engineering.In order to improve the calculation efficiency,the complete coordination method will be used to deal with the connection state between the plate and the member.The thickness reduction factor is0.82.(3)Next,in this chapter,the structural model of aluminum alloy honeycomb plate singlelayer composite latticed shell is established according to the engineering example.The influence of stiffness of supporting member,rise span ratio and support form on the static performance of roof is studied.The results show that for the same single-layer composite lattice shell roof structure system,under the same load,the greater the stiffness of supporting members is,the smaller the deformation of the roof is.When the rise span ratio is 1:7,the overall displacement and internal force of members are the minimum.The control of internal force and displacement is better than that of hinge joint.Under the same internal and external conditions,the maximum deformation of the composite latticed shell with fixed support is about 60% of that of hinged support.(4)Last,the static performance and seismic wind-induced response of composite latticed shell and plate free reticulated shell are compared.The results show that the strength,stiffness and bearing capacity of aluminum alloy plate bar composite latticed shell are significantly better than those of the same span.In conclusion,Through the systematic research of this paper,and Combined with the author’s experience in hangar structural engineering design.It is suggested that in the structural design of hangar in the coastal area.This kind of composite latticed shell structure with good wind resistance,earthquake resistance and durability can be considered.