Design And Mechanical Behavior Of Rapidly Assembled Helipad

In many emergency rescue situations,helicopters will have certain security risks while landing directly due to complex terrain and other environmental constraints.The design of the rapidly assembled helipad is studied in this paper which can be quickly assembled in a variety of terrains and easy to be disassembled and transported,effectively solving the problem of field landing in emergency rescue situations.The specific theoretical issues related to helicopter landing are put forward in this paper based on the principle and design of the rapidly assembled helipad and some principles are elaborated and verified combined with relevant analysis and experiments which expands the thinking for the research and experimental methods of the new technology of the rapidly assembled helipad.The design of the rapidly assembled helipad mainly includes two parts: scheme design and multi-objective optimization of the deck.The research status of related technologies at home and abroad is summarized in the paper,it is compared and analyzed from various aspects,and related experimental methods are described.According to the functional requirements and design overview of the rapidly assembled helipad,a variety of principle design schemes under the different design ideas of the leg-type rapidly assembled helipad and the legless rapidly assembled helipad are proposed,the final scheme is determined by physical model assembly experiment and plane dimension planning and its structural design is introduced in detail.Multi-objective optimization design for the structure of the deck is carried out in the paper,which is one of the most important part of the rapidly assembled helipad.Firstly,the parametric model and the finite element model of the deck are established,and the static analysis is carried out for the most dangerous working conditions.Then design variables are selected,and the experimental design is carried out by the Latin hypercube sampling to establish a second-order response surface model.The next,a mathematical model of the optimization problem is established and multi-objective optimization is carried out using genetic algorithm.Finally,a design scheme is selected in the Pareto feasible solution,and then the design variables are re-analyzed after rounded-off,verifying the optimization results.The analysis of mechanical behavior of the rapidly assembled helipad mainly includes two parts: finite element analysis and experimental research.The static analysis of the quick connector is firstly conducted in this paper,in which a unit deck-ground finite element model is built and static analysis of various loading positions are compared.The free modal analysis and transient dynamics analysis of the unit deck are then carried out,and an explicit dynamic analysis is performed to simulate the airdrop of the deck.Finally,in order to verify the assembly and load bearing characteristics of the rapidly assembled helipad,the paper selects simulation materials of the ground and proposes a new experimental method and experimental scheme,and mainly carries out experimental prototype assembly experiment,connection strength experiment,rapidly assembled helipad deformation test and load impact test.