To promote the recycling of reclaimed asphalt pavement(RAP),epoxy resin was used to prepare the epoxy-recycled asphalt mixtures.The effect of epoxy resin on the properties of aged asphalt binder was investigated based...To promote the recycling of reclaimed asphalt pavement(RAP),epoxy resin was used to prepare the epoxy-recycled asphalt mixtures.The effect of epoxy resin on the properties of aged asphalt binder was investigated based on the tensile test,flexural creep test,and laser scanning confocal microscopy.The curing characteristics and the mechanical performance of recycled asphalt with different epoxy contents were explored.The results show that the low-temperature performance,ductility,and strength of the aged asphalt binder were significantly improved when the epoxy content reached 40%.The curing time of epoxy-recycled asphalt should be at least 4 d to ensure the formation of good internal spatial network structure.展开更多
Polymer modification in the field of construction engineering has a history nearly 90 years. Mechanical properties, water resistance, chemical resistance and durability to some extent have been improved by different p...Polymer modification in the field of construction engineering has a history nearly 90 years. Mechanical properties, water resistance, chemical resistance and durability to some extent have been improved by different polymer modification although those modifications are classified into physical modification. To obtain better performance of cementitious materials, chemical modifications have been tested. In this study, epoxy has been designed as a predominant modifier in the modified system with its corresponding hardener. Amino sulfonate, the additive, has been used to improve the system＇s workability. Functional silane, as it has special functional groups, was used to set up the connections among epoxy, cement moiety and amino sulfonate. The investigation carried out by IR, Raman spectroscopy, DSC and NMR reveals that the chemical connections have been set up among all the components in the modified system. Flexural tests results present the good effect of the chemical modification as the flexural strength and strain have been improved substantially.展开更多
In polymer modified cementitious materials, it is hard to set up a chemical connection between the added polymer and the cement moiety. In this study FS （functional silane） was adopted to form this connection as a b...In polymer modified cementitious materials, it is hard to set up a chemical connection between the added polymer and the cement moiety. In this study FS （functional silane） was adopted to form this connection as a bridge component which has the functional group forming bonds with polymer. To testify the connection between FS and cement moiety, Q2/Q1 ratio （Qx： intensity ratio） investigation was carried out by the means of quantitative solid state 29Si MAS NMR. The results show that the Q2/Q1 ratio has increased with the addition of FS which indicates that the silicon chain length has increased, and the quantity of silicon atoms at site of Q2, chain site, has enhanced, showing that the silicon atom of FS has connected to the silicon chain of cement moiety by the bond ＂-Si-O-Si-＂ formation.展开更多
基金Funded by the National Natural Science Foundation of China(No.52378444)。
文摘To promote the recycling of reclaimed asphalt pavement(RAP),epoxy resin was used to prepare the epoxy-recycled asphalt mixtures.The effect of epoxy resin on the properties of aged asphalt binder was investigated based on the tensile test,flexural creep test,and laser scanning confocal microscopy.The curing characteristics and the mechanical performance of recycled asphalt with different epoxy contents were explored.The results show that the low-temperature performance,ductility,and strength of the aged asphalt binder were significantly improved when the epoxy content reached 40%.The curing time of epoxy-recycled asphalt should be at least 4 d to ensure the formation of good internal spatial network structure.
基金Funded by the National Basic Research Program of China(973 Program(No.2009CB623200)
文摘Polymer modification in the field of construction engineering has a history nearly 90 years. Mechanical properties, water resistance, chemical resistance and durability to some extent have been improved by different polymer modification although those modifications are classified into physical modification. To obtain better performance of cementitious materials, chemical modifications have been tested. In this study, epoxy has been designed as a predominant modifier in the modified system with its corresponding hardener. Amino sulfonate, the additive, has been used to improve the system＇s workability. Functional silane, as it has special functional groups, was used to set up the connections among epoxy, cement moiety and amino sulfonate. The investigation carried out by IR, Raman spectroscopy, DSC and NMR reveals that the chemical connections have been set up among all the components in the modified system. Flexural tests results present the good effect of the chemical modification as the flexural strength and strain have been improved substantially.
基金Funded by the National Basic Research Program of China(973 Program(No.2009CB6232007)
文摘In polymer modified cementitious materials, it is hard to set up a chemical connection between the added polymer and the cement moiety. In this study FS （functional silane） was adopted to form this connection as a bridge component which has the functional group forming bonds with polymer. To testify the connection between FS and cement moiety, Q2/Q1 ratio （Qx： intensity ratio） investigation was carried out by the means of quantitative solid state 29Si MAS NMR. The results show that the Q2/Q1 ratio has increased with the addition of FS which indicates that the silicon chain length has increased, and the quantity of silicon atoms at site of Q2, chain site, has enhanced, showing that the silicon atom of FS has connected to the silicon chain of cement moiety by the bond ＂-Si-O-Si-＂ formation.
