本研究探讨将CFBC(circulating fluidized bed combustion,CFBC,循环式流体化床)水化灰混和其它不同胶结材与再生粒料,制成不同控制性低强度材料(controlled-low-strength-materials,CLSM)在不同发展龄期之基本力学性质与体积稳定性质,...本研究探讨将CFBC(circulating fluidized bed combustion,CFBC,循环式流体化床)水化灰混和其它不同胶结材与再生粒料,制成不同控制性低强度材料(controlled-low-strength-materials,CLSM)在不同发展龄期之基本力学性质与体积稳定性质,研究结果显示:(1)水库淤泥比例过多时,会降低工作性;(2)高炉石比例越多,可提升抗压强度及快速达到落沉时间,但也使氯离子含量增加;(3)添加CFBC飞灰与炉石粉,明显增加膨胀量。展开更多
The effects of green high performance concrete (GHPC) admixture on the anti-chloride permeability and anti- chloride corrodibility of concrete are studied by a series of experiments designed on the basis of the diffus...The effects of green high performance concrete (GHPC) admixture on the anti-chloride permeability and anti- chloride corrodibility of concrete are studied by a series of experiments designed on the basis of the diffusion principle and electro-chemical principle. The GHPC admixture consists of fly ash, gangue, slag, red mud, etc., of which the mass fraction of industrial residues is over 96 %. The anti-permeabilities and anti-corrodibilities of the tested GHPC and normal concrete (NC) are evaluated by the Diffusion Coefficients of chloride which was obtained by measuring the concentration of chloride in the tested systems by the voltage difference method. It is found that the adoption of GHPC admixture greatly improves the anti-chloride permeability and anti-chloride corrodibility by modifying the inner structure and contracting the porosity of concrete to the reduce considerably the diffusion rate of chloride. The admixture is desirable regarding its engineering performances as well as economical and environmental interests.展开更多
The effect of rutile crystal shapes on its settlement in a modified slag was studied by theoretical analysis,FactSage simulation,X-ray diffraction and scanning electron microscopy.The results show that the settling ve...The effect of rutile crystal shapes on its settlement in a modified slag was studied by theoretical analysis,FactSage simulation,X-ray diffraction and scanning electron microscopy.The results show that the settling velocities of spherical rutile crystals are faster than those of other shapes of rutile crystals under the same volume conditions,and the shape transformation of rutile crystals from rod to sphere can be achieved by adding titanium slag to Ti-bearing blast furnace slag.The volume fractions of the rutile crystals in the upper and lower parts of the modified slag are 30%and 71%when the added titanium slag increases to 278 g,indicating that rutile settling is obvious.Due to the rutile settling,half shaker sorting task is saved,and the recovery rate of TiO2 is significantly increased.The TiO2 content of rutile is greater than 93%,and the total content of CaO and MgO is less than 0.4%,meeting the requirements for the raw materials of titanium white in the chloride process.展开更多
The deterioration of concrete by sulfuric acid attack in sewage environments has become a serious problem for many existing sewage structures. In this study, the properties of concrete using the blast furnace slag hav...The deterioration of concrete by sulfuric acid attack in sewage environments has become a serious problem for many existing sewage structures. In this study, the properties of concrete using the blast furnace slag have been examined. It was shown that by using the blast furnace slag fine aggregate and blast furnace slag fine powder, it is possible to enhance the resistance of mortar and concrete to sulfuric acid. The resistance to sulfuric acid of mortar and concrete can be improved by using a blast-furnace slag fine aggregate in the total amount of fine aggregate. When mortar or concrete reacts to sulfuric acid, dihydrated gypsum film is formed around the particulate of the fine aggregate. This dihydrated gypsum film could retard the penetration of sulfuric acid, thus, improving the resistance to sulfuric acid. Furthermore, it has been proved that the relationship between the erosion depth by sulfuric acid attack and the product of immersion period and concentration of sulfuric acid can be expressed linearly. However, this relationship is dependent on the type of materials of concrete.展开更多
文摘本研究探讨将CFBC(circulating fluidized bed combustion,CFBC,循环式流体化床)水化灰混和其它不同胶结材与再生粒料,制成不同控制性低强度材料(controlled-low-strength-materials,CLSM)在不同发展龄期之基本力学性质与体积稳定性质,研究结果显示:(1)水库淤泥比例过多时,会降低工作性;(2)高炉石比例越多,可提升抗压强度及快速达到落沉时间,但也使氯离子含量增加;(3)添加CFBC飞灰与炉石粉,明显增加膨胀量。
文摘The effects of green high performance concrete (GHPC) admixture on the anti-chloride permeability and anti- chloride corrodibility of concrete are studied by a series of experiments designed on the basis of the diffusion principle and electro-chemical principle. The GHPC admixture consists of fly ash, gangue, slag, red mud, etc., of which the mass fraction of industrial residues is over 96 %. The anti-permeabilities and anti-corrodibilities of the tested GHPC and normal concrete (NC) are evaluated by the Diffusion Coefficients of chloride which was obtained by measuring the concentration of chloride in the tested systems by the voltage difference method. It is found that the adoption of GHPC admixture greatly improves the anti-chloride permeability and anti-chloride corrodibility by modifying the inner structure and contracting the porosity of concrete to the reduce considerably the diffusion rate of chloride. The admixture is desirable regarding its engineering performances as well as economical and environmental interests.
基金Project(2015BAB18B00)supported by the National Science and Technology Support Program of China。
文摘The effect of rutile crystal shapes on its settlement in a modified slag was studied by theoretical analysis,FactSage simulation,X-ray diffraction and scanning electron microscopy.The results show that the settling velocities of spherical rutile crystals are faster than those of other shapes of rutile crystals under the same volume conditions,and the shape transformation of rutile crystals from rod to sphere can be achieved by adding titanium slag to Ti-bearing blast furnace slag.The volume fractions of the rutile crystals in the upper and lower parts of the modified slag are 30%and 71%when the added titanium slag increases to 278 g,indicating that rutile settling is obvious.Due to the rutile settling,half shaker sorting task is saved,and the recovery rate of TiO2 is significantly increased.The TiO2 content of rutile is greater than 93%,and the total content of CaO and MgO is less than 0.4%,meeting the requirements for the raw materials of titanium white in the chloride process.
文摘The deterioration of concrete by sulfuric acid attack in sewage environments has become a serious problem for many existing sewage structures. In this study, the properties of concrete using the blast furnace slag have been examined. It was shown that by using the blast furnace slag fine aggregate and blast furnace slag fine powder, it is possible to enhance the resistance of mortar and concrete to sulfuric acid. The resistance to sulfuric acid of mortar and concrete can be improved by using a blast-furnace slag fine aggregate in the total amount of fine aggregate. When mortar or concrete reacts to sulfuric acid, dihydrated gypsum film is formed around the particulate of the fine aggregate. This dihydrated gypsum film could retard the penetration of sulfuric acid, thus, improving the resistance to sulfuric acid. Furthermore, it has been proved that the relationship between the erosion depth by sulfuric acid attack and the product of immersion period and concentration of sulfuric acid can be expressed linearly. However, this relationship is dependent on the type of materials of concrete.
