The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly ash.The durability testing showed that the strength ...The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly ash.The durability testing showed that the strength of RBM with the blast furnace slag addition of 1wt%,3wt%and 5wt%reached 3.81,4.87,and 5.84 MPa after 5 freezing–thawing(F–T)cycles and reached 5.21,5.75,and 6.98 MPa after 20 weting–drying(W–D)cycles,respectively.The results also indicated that hydration products were continuously formed even during W–D and F–T exposures,resulting in an increase of the strength and durability of RBM.The observed increase of macropores(>1μm)after F–T and W–D exposures suggested that the mechanism of RBM deterioration is pore enlargement due to cracks that develop inside their matrix.Moreover,the F–T exposure showed a greater negative effect on the durability of RBM compared to the W–D exposure.The leaching tests showed that sodium and heavy metals were solidified below the minimum requirement,which indicates that these wastes are suitable for use as a natural material replacement in road base construction.展开更多
为提高彩色沥青路面色彩耐久性并研究其抗滑性能,采用有机硅-聚丙酸酯(silane-modified polyacrylate,SMP)对彩色沥青玛蹄脂碎石混合料(color stone mastic asphalt,CSMA)和彩色开级配抗滑表层(color open graded friction course,COGF...为提高彩色沥青路面色彩耐久性并研究其抗滑性能,采用有机硅-聚丙酸酯(silane-modified polyacrylate,SMP)对彩色沥青玛蹄脂碎石混合料(color stone mastic asphalt,CSMA)和彩色开级配抗滑表层(color open graded friction course,COGFC)2种混合料改性,借助小型加速加载设备进行对彩色沥青路面进行色彩耐久性评价,并通过三维扫描仪进行路面纹理信息采集,分析路面三维参数与其抗滑性能之间的关系。结果表明,SMP改性剂可有效提高CSMA、COGFC两种混合料的抗磨耗能力,提升彩色沥青色彩耐久性;CSMA及COGFC路面抗滑性能受到不同三维参数的影响,路面的摩擦系数模型由各自相关因子控制,增加路面暴露的集料数量和使用尖角集料能使彩色沥青路面的抗滑性能得到提升。展开更多
A high strength self-compacting pervious concrete(SCPC) with top-bottom interconnected pores was prepared in this paper. The frost-resisting durability of such SCPC in different deicing salt concentrations(0%, 3%, 5%,...A high strength self-compacting pervious concrete(SCPC) with top-bottom interconnected pores was prepared in this paper. The frost-resisting durability of such SCPC in different deicing salt concentrations(0%, 3%, 5%, 10%, and 20%) was investigated. The mass-loss rate, relative dynamic modulus of elasticity, compressive strength, flexural strength and hydraulic conductivity of SCPC after 300 freeze-thaw cycles were measured to evaluate the frost-resisting durability. In addition, the microstructures of SCPC near the top-bottom interconnected pores after 300 freeze-thaw cycles were observed by SEM. The results show that the high strength SCPC possesses much better frost-resisting durability than traditional pervious concrete(TPC) after 300 freeze-thaw cycles, which can be used in heavy loading roads. The most serious freeze-thaw damage emerges in the SCPC immersed in the 3% of Na Cl solution, while there is no obvious damage in 20% of Na Cl solution. Furthermore, it can be deduced that the high strength SCPC can be used for 100 years in a cold environment.展开更多
基金the National Natural Science Foundation of China(Nos.51574024 and U1760112)Fundamental Research Funds for the Central Universities of China(FRF-AT-19-007).
文摘The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly ash.The durability testing showed that the strength of RBM with the blast furnace slag addition of 1wt%,3wt%and 5wt%reached 3.81,4.87,and 5.84 MPa after 5 freezing–thawing(F–T)cycles and reached 5.21,5.75,and 6.98 MPa after 20 weting–drying(W–D)cycles,respectively.The results also indicated that hydration products were continuously formed even during W–D and F–T exposures,resulting in an increase of the strength and durability of RBM.The observed increase of macropores(>1μm)after F–T and W–D exposures suggested that the mechanism of RBM deterioration is pore enlargement due to cracks that develop inside their matrix.Moreover,the F–T exposure showed a greater negative effect on the durability of RBM compared to the W–D exposure.The leaching tests showed that sodium and heavy metals were solidified below the minimum requirement,which indicates that these wastes are suitable for use as a natural material replacement in road base construction.
文摘为提高彩色沥青路面色彩耐久性并研究其抗滑性能,采用有机硅-聚丙酸酯(silane-modified polyacrylate,SMP)对彩色沥青玛蹄脂碎石混合料(color stone mastic asphalt,CSMA)和彩色开级配抗滑表层(color open graded friction course,COGFC)2种混合料改性,借助小型加速加载设备进行对彩色沥青路面进行色彩耐久性评价,并通过三维扫描仪进行路面纹理信息采集,分析路面三维参数与其抗滑性能之间的关系。结果表明,SMP改性剂可有效提高CSMA、COGFC两种混合料的抗磨耗能力,提升彩色沥青色彩耐久性;CSMA及COGFC路面抗滑性能受到不同三维参数的影响,路面的摩擦系数模型由各自相关因子控制,增加路面暴露的集料数量和使用尖角集料能使彩色沥青路面的抗滑性能得到提升。
基金Funded by the National Natural Science Foundation of China(No.51878081).
文摘A high strength self-compacting pervious concrete(SCPC) with top-bottom interconnected pores was prepared in this paper. The frost-resisting durability of such SCPC in different deicing salt concentrations(0%, 3%, 5%, 10%, and 20%) was investigated. The mass-loss rate, relative dynamic modulus of elasticity, compressive strength, flexural strength and hydraulic conductivity of SCPC after 300 freeze-thaw cycles were measured to evaluate the frost-resisting durability. In addition, the microstructures of SCPC near the top-bottom interconnected pores after 300 freeze-thaw cycles were observed by SEM. The results show that the high strength SCPC possesses much better frost-resisting durability than traditional pervious concrete(TPC) after 300 freeze-thaw cycles, which can be used in heavy loading roads. The most serious freeze-thaw damage emerges in the SCPC immersed in the 3% of Na Cl solution, while there is no obvious damage in 20% of Na Cl solution. Furthermore, it can be deduced that the high strength SCPC can be used for 100 years in a cold environment.
