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Snow-melting pavement with electric heating pipes (SMP-EHP) is used to mitigate the accumulated snow problem for large longitudinal slopes or slippery roads. To improve its operation efficiency, the structural model and thermal simulations of the SMP-EHP were studied. The electric heating pipe’s embedded spacing (s) and embedded depth (d), the heating power (P) and the wind velocity (v) were considered as the input parameters. The total heating time (THT) and the lost energy rate (LER) for the melting process were considered as the prediction responses. The prediction models for THT and LER were proposed by using Response Surface Methodology (RSM). The single input parameter’s effects on prediction responses and the interactions between them were analyzed by the assisted thermal simulation. The rationality of the prediction models and simulations were validated by statistical analysis and experiments. Additionally, for decreasing THT, LER, a multi-objective optimization on THT and the lost energy (LE) was built through the genetic algorithm. Through optimization, the recommended parameters are proposed. The results and suggestions could efficiently guide the operation of SMP-EHP.

The method of ice-snow melting pavement (ISMP) with electric heating pipes is presented to achieve the purpose of environmental protection, intelligence, and high efficiency. In order to determine the thermal field of the ISMP and prejudge the feasibility of heating schemes, two thermal field prediction models are proposed in this paper. The one is a theory model based on line heat source theory and virtual image method, the other is a semi-empirical formula based on theory model and experiment discussion. The effectiveness of the two models is verified by the heating experiment results of concrete slabs with electric heating pipes. Differences and advantages in the two models are compared. In summary, the theory model has the wider range of applications than the semi-empirical formula, but the semi-empirical formula is closer to the practice, and easier to conduct calculation than the theory model.

The automatically snow-melting system with the electric heating pipes (AS-EHP) is applied in infrastructures (concrete pavement, parking apron, garage entrances and municipal road) in cold regions to mitigate the accumulated snow problem. In order to reduce the energy consumption (EC) and improve the energy utilization rate (EUR) of AS-EHP, the analysis about EC and EUR is investigated. The melting process of AS-EHP is divided into two phases which include preheating the infrastructures and melting. The influence and sensitivity analysis between the inputs (the pipes' embedded spacing and embedded depth, heating power and wind velocity) and the outputs (EC and EUR) are found and compared in two phases by thermal simulation. The applicability and rationality of the simulation are verified by snow melting experiments. According to the simulation, decreasing embedded spacing and depth in phase 1 and phase 2 could reduce EC and improve EUR. In the two phases, the heating power is suggested to be 100 W/m-140 W/m under the condition that the heating pipe’ embedded spacing is 0.10 m–0.25 m, the depth is 0.06 m–0.12 m, and the wind velocity is 0 m/s–15 m/s. The results and suggestions could be used to efficiently guide the scheme design and operation control of AS-EHP in infrastructures.

The equivalent plasticity strain (EPS) of snow-melting heated pavement concrete that exposed to inner elevated temperatures is analyzed with finite element simulations. An optimal mix proportion of the concrete with high thermal conductivity was obtained through mechanical and thermal experiments, which helps facilitate reducing the damage in snow-melting pavement. A three-dimensional (3D) finite element model is developed based on the concrete damage plastic (CDP) model with parameters. The EPS is considered as the performance evaluation index for damage in snow-melting heated pavement concrete. Based on the results of finite element simulations, the EPS of snow-melting heated pavement concrete that exposed to inner elevated temperatures was analyzed under different pavement structures and external conditions. Furthermore, two EPS prediction models were proposed: the one is for EPS and the inner elevated temperature, the other is for EPS and five key factors. The outputs of 3D finite element simulations were verified by an experiment result. It indicated that numerical results agreed with experimental results very well. A prediction and evaluation method of damage for snow-melting heated pavement concrete was established as well.