Mechanical and Physical Properties of Alkali-Activated Granulated Blast Furnace Slag/Metakaolin Blends
| Autor: | CHANG, CHI-WEN, 張繼文 |
|---|---|
| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 104 The hardening mechanism of alkali-activated slag/metakaolin is totally different from the hydration of Portland cement. The alkali-activated binder is under development now, and different alkali-activators and materials will result in different results. Especially the effects of using the blend of pozzolans (such as slag/metakaolin) such as the hardening mechanism, reactants, mechanical properties, durability and microstructure require long-term experimental data and research. The goal of this study is to investigate the mechanical and physical properties of alkali-activated slag/metakaolin mortar. The results show that when the liquid/binder ratio is 0.35, all mixes in this research owned a lower fluidity value than the control group. The major factors influencing the fluidity value are the alkali modulus and the content of Na2O in the alkali-activator. When the alkali modulus and/or the Na2O content are larger, the fluidity value is larger. In addition, the initial setting times of all groups are shorter than the control group. Except a higher liquid/binder ratio, the ratio of amount of slag over amount of metakaolin of 30/70 contributes to these results. No matter which liquid/binder ratio is adopted, the compressive strength increases as the mass ratio of slag/metakaolin increases. Especially for the mix with liquid/binder=0.35, slag/metakaolin=70/30, alkali modulus=1.0, Na2O content=6%, the compressive strength is the highest one. Furthermore, within the category of this study (alkali modulus of 0.8, 1.0 and 1.23) the compressive strength and splitting tensile strength decrease slightly as the alkali modulus increases. The changes of Na2O content (in this study Na2O=4%, 6% and 8%) do not show significant influence on the compressive strength and splitting tensile strength. As the mass ratio of slag/metakaolin increases, the splitting tensile strength increases no matter which liquid/binder ratio is used. When the liquid/binder ratios are 0.35 and 0.50, the water absorption rate of 35M6 group is the smallest (5.7%) which indicating the volume of connected pores is smaller. This conclusion can be also confirmed by the results of compressive strength. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|