The strength and microstructural analysis of recycled geopolymer are presented in this paper.Five kinds of geopolymers containing 0%,20%,50%,80%and 100%of recycled geopolymer powder were prepared using metakaolin as t...The strength and microstructural analysis of recycled geopolymer are presented in this paper.Five kinds of geopolymers containing 0%,20%,50%,80%and 100%of recycled geopolymer powder were prepared using metakaolin as the source material.The alkali activator solution was a mixture of sodium silicate(Na_(2)SiO_(3))and 12 M sodium hydroxide(NaOH).The change laws of compressive and flexural strength of recycled geopolymer specimens were investigated.And the microscopic characteristics were carried out by SEM,XRD and FTIR to observe the internal morphology and analyze changes in components of recycled geopolymers at different substitution rates.The results show that,with the increase of substitution rate of recycled geopolymer powder,the mechanical properties of recycled geopolymers degenerate and the looser structure are formed.When the substitution rate is less than 50%,the recycled geopolymer specimen meets the use requirements of heavy traffic load class.And the specimen with 80%of substitution rate satisfies the requirements of plastering mortar.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Funded by the National Natural Science Foundation of China(No.52008046)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No.19KJB560007)+1 种基金the Innovation Project of the Jiangsu Postgraduate Research of China(No.KYCX19_1788)the Research Start-up Funding of Changzhou University(No.ZMF18020307)。
文摘The strength and microstructural analysis of recycled geopolymer are presented in this paper.Five kinds of geopolymers containing 0%,20%,50%,80%and 100%of recycled geopolymer powder were prepared using metakaolin as the source material.The alkali activator solution was a mixture of sodium silicate(Na_(2)SiO_(3))and 12 M sodium hydroxide(NaOH).The change laws of compressive and flexural strength of recycled geopolymer specimens were investigated.And the microscopic characteristics were carried out by SEM,XRD and FTIR to observe the internal morphology and analyze changes in components of recycled geopolymers at different substitution rates.The results show that,with the increase of substitution rate of recycled geopolymer powder,the mechanical properties of recycled geopolymers degenerate and the looser structure are formed.When the substitution rate is less than 50%,the recycled geopolymer specimen meets the use requirements of heavy traffic load class.And the specimen with 80%of substitution rate satisfies the requirements of plastering mortar.
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.
