Papers by Keyword: Covering Layer

Abstract: The safety operation of a concrete face rockfill dam (CFRD) built on covering layers depend on the integrity of its water stop system. So analyzing the dam seepage field before and after joint sealing damaged is significant, which includes the study of the influence on the dam seepage behavior when the water stop of peripheral joint and slab joint were damaged. In this paper, taken a specific hydropower station project as an example, the numerical analysis models of a CFRD for simulating the different water stop damage and failure types were established. Then the influence mechanism how the damage of the peripheral joint and slab joint affects the seepage gradient, saturated surface and seepage discharge inside the dam was analyzed, and the influence values were obtained. Therefore, the water stop area that needs to focus on is ascertained when the dam anti-seepage system was arranged.

Abstract: Floor radiant heating system has many advantages, energy and space saving, for example. The radiant floor is the radiator of floor radiant heating system, and its thermal parameters influence surface temperature distribution and comfort. In this paper, mathematical model of heat exchange coil under floor was established, and boundary heat transfer conditions were given. Based on these, surface temperature of different covering layer was calculated. According to the results, using different covering layer, the floor surface temperature has a great difference. Using wooden floor as cover material, the floor surface temperature is more moderate and uniform.

Abstract: To get basic information on corrosion of metals under sewage sludge environment, in this work, the corrosion behavior of SAE1045 steel under SiO2 gel with 3 wt% NaCl was investigated by electrochemical polarization method. The results show that the self-orrosion potential of the steel move to more negative value in SiO2 gel comparing to those in aqueous solution. It was found by SEM and EDX measurements that, after 15 days of wilhelmy test in SiO2 gel, a dense covering layer containing a lot of Si appeared on the surface of steel, which was attributed to the difference of corrosion behavior for the metal under SiO2 gel and aqueous solution.

Abstract: Based on the feasibility of ore drawing simulation with PFC, a PFC numerical simulation was performed on the surface deformation problem in Jinshandian mine. With PFC numerical simulation software, ore drawing simulations were carried out under four covering layer thicknesses of 15 meters, 20 meters, 25 meters and 30 meters. By comparing the deformations of surface loess layer according to the simulation results of four groups, related equation was obtained.