Study On Cement Concrete Pavement Of Snow Melting And Deicing

Icy roads and accumulated snow in the winter or freezing areas seriously affected the country's transport, economic, and normal outdoor activities and work, at the same time they became the main factors of growth of the traffic accidents rate.In order to resolve the icy roads and accumulated snow, countries around the world made a lot of research to find out a number techniques and methods for suppression, control and elimination of snow and ice, but most of these methods have shortcomings, like low efficiency, high cost, corrosive environment and the destruction of road infrastructure, the small scope of application, a lot of energy consumption, recycling sustainability is very poor. In recent years, there is growing interest and pursuit for solar energy technology on melting snow and ice, which is more promising, environmental protection and energy conservation, sustainable use. In this area, solar energy systems technology, snow melt heat transfer model and calculation of road, experiment and demonstration projects are carried out by national scholars, but there are hardly any research on the snow melt (ice) special pavement structure and material, and mechanical property of the snow melt for different pavement (test and numerical simulation). So to carry out such research is a solid foundation and sufficient condition that is to promote solar energy technology (storage, conversion, control) applied to the field of road snow melting.For the above problems, this paper mainly to carry out the following studies:(1) Study on material properties of snow melt pavement. System testing and optimization study on thermal conductivity and mechanical properties of three kinds of pavement materials are carried out, the optimum material type and composition of the snow melt pavement is recommended based on mechanical strength and thermal conductivity; (2) Simulation tests on snow melt pavement structure. A variety of pavement structure are established, single-tube trabeculae test and interlayer mechanical property test of thermal insulation layer are completed, a small full-scale simulation test of pavement slab is proposed and completed, these tests provide the basis for the optimal structure of snow melt pavement; (3) Snowmelt pavement temperature rise simulation and ice-melting effect tests. Snowmelt pavement temperature rise simulation test on small full-scale slab is carried out under ice-melting conditions and not ice-melting conditions, (minimum) optimum total power of pipe network under different environmental temperatures are recommended according to different ice-melting effect of different programs, judging criteria is provided for engineering applications; (4) Snow melt pavement interlayer stress analysis. The mechanical theory of snow melting and deicing special pavement structure is derived, the theory solution of thin slab on four-layer elastic foundation is improved, relationship between a number of influencing factors and the interlaminar stress, and regularity for variation of stresses are calculated and obtained; (5) Numerical calculation and simulation analysis on snow melting and deicing special pavement. Finite element model of snow melting and deicing special pavement structure is established, combined with the existing specifications, calculation and analysis are completed from the temperature, load, coupling three aspects, according to indoor structural tests, ultimate pipe network heating temperature, ultimate load, and ultimate program of pipe network which pavement can withstand are obtained; (6) Comparison and optimization on program for snow melting and deicing special pavement structure. Using gray theory and data envelopment analysis, decision-making analysis and effectiveness evaluation for diferent pavement structures are completed, so as to master the degree of merits and feasibility of the program.Snow melting and deicing special pavement structures and materials were studied through tests (materials, structures, warming and melting ice) and simulation computation (the influence law on pavement structures of temperature, load, and coupled stress) in the thesis. The pipe network heating temperature, load and pipe network programs were found at limit state. Research results provide the scientific basis for the selection of snow melting and deicing pavement programs, and lay a solid foundation for the application and promotion of solar energy technology.