Proposal of the permafrost slope supporting structure with framed unpowered #br#
acceleration convection anchor and its theoretical calculation method
Dong Jianhua1,2 Bao Wanfei1,2
1. Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province, Lanzhou University of Technology,
Lanzhou 730050, China;2. Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,
Lanzhou University of Technology, Lanzhou 730050, China
Abstract:Aiming at the problem of freeze-thaw collapse of permafrost slope, a permafrost slope supporting structure with framed unpowered acceleration convection anchor was proposed by adopting unpowered ventilation technology, air-duct cooling technology and anchoring technology, and then its work mechanism was elaborated. Based on the theories of heat transfer and ventilation engineering, the calculation model of heat transfer between unpowered acceleration convection anchor and soil was established. Besides, a theoretical calculation method for the thermal effect of unpowered acceleration convection anchor was developed. Based on the Winkler elastic foundation beam model, a calculation model of cooperation between the supporting structure with framed unpowered acceleration convection anchor and soil was established. Furthermore, a theoretical calculation method for the mechanical effect of the permafrost slope supporting structure with framed unpowered acceleration convection anchor was proposed. Based on the calculation examples, the thermo-mechanical effect of the permafrost slope supporting structure with framed unpowered acceleration convection anchor was analyzed by the proposed theoretical calculation method, which was then verified by the Moisture-Heat-StressCoupled Analysis Software. The results showed that: ① The unpowered hood greatly enhances the ventilation of unpowered acceleration convection anchor, increases the heat transfer between the cold air and the soil, and then the freeze-thaw interface of the permafrost slope rises year by year; ② the new structure can weaken the frost heaving effect of the slope soil and improve the stability of the permafrost slope; ③ The theoretical calculation method has been proved to be accurate and reasonable, and it can provide a theoretical basis for the design of permafrost slope supporting structure with framed unpowered acceleration convection anchor.