Durability and Reliability of Space Rod Structures Made of Polymers with Nodes Made of Composite Materials at Cyclic Changes in Heat and Humidity Parameters of Operation

Structural tubular elements made of non-plasticized polyvinyl chloride (PVC), one of the cheap thermoplastic materials characterized by high resistance to various chemically aggressive environments, are considered. The developed plastic cross-rod spatial structure made of PVC pipes is recommended for closed ground structures (hot houses, greenhouses, glass houses), warehouses of mineral fertilizers and farm products, covered parking lots for cars and agricultural machines, gas stations and car service stations, offshore stationary deep-water platforms, etc. Low and high temperatures significantly affect changes in the mechanical characteristics of structural plastics: tensile strength/compression, bending, loss of stability, which ultimately reduces the operational reliability and durability of the cross-rod spatial structure. Therefore, in the calculations of the stress-strain state, it is necessary to take into account the non-stationary heat transfer in the load-bearing space rod systems. The derivation of differential heat transfer equations based on the application of the law of conservation of energy to an infinitesimal element of the environment is considered, taking into account the heat flows through the surface of this element, as well as the release or absorption of thermal energy in the volume of this element. Taking into account the influence of the process temperature on PVC tubular elements in time inside the premises during the operation of the cross-rod spatial structure will make it possible to increase the reliability and durability for predicting their technical condition, for example, by forcibly changing the temperature regime with the help of special devices.

S.V. FEDOSOV¹, Doctor of Sciences (Engineering), Academician of RAASN (This email address is being protected from spambots. You need JavaScript enabled to view it.);
S.A. MALBIEV², Candidate of Sciences (Engineering), Leading researcher

¹ National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)
² “Engineer-Story” NPP LLC (office 103, 15a, Krasnykh Zor’ Street, Ivanovo, 153003, Russian Federation)

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