高細度爐石混凝土微觀結構及水化作用探討

Abstract

近年來，營建產業為了節省水泥用量會添加卜作嵐材料到混凝土裡取代水泥作為膠結材使用。卜作嵐材料有爐石、飛灰、矽灰等等，根據添加材料種類的不同，混凝土會顯現不同的特性，而不同來源、化學成份、物理特性的卜作嵐材料添加入混凝土後所表現的性質差異會很大。爐石為一種卜作嵐材料，它是煉鋼的副產品，當細度研磨至更高時，高細度的爐石粉因為反應面積較大，水化反應會比一般細度爐石更快速，故其微觀性質與工程性質會與一般添加卜作嵐材料的混凝土不同。 混凝土材料逐漸從巨觀工程性質的研究轉變為微觀性質的探討，透過各種微觀試驗來了解材料反應的機制，以期能透過改變材料特性來達到特定的混凝土性質表現。 本研究主要使用高細度爐石粉、一般細度爐石粉取代水泥作為膠結系統並設計3 個爐石取代率搭配五個齡期，利用三項微觀試驗分別為MIP 壓汞孔隙法、XRD 繞射試驗、TG/DTA 試驗的結果分析高細度爐石粉與一般細度爐石粉水化後對於混凝土微觀性質影響的差異，並進行抗壓強度試驗對照微觀試驗的結果，了解高細度爐石粉添加於混凝土後其微觀性質如何影響巨觀工程性質。

In recent years , in order to save cement consumption,the construction industry will replace cement with pozzolan materials as binder materials in concrete.Pozzolan materials include slag, fly ash, silica fume , depending on the type of material added,concrete will exhibit different characteristics.Pozzolan materials with different sources、chemical compositions、physical feature added into concrete would show big difference in concrete’s performance.Slag is a kind of pozzolan materials, it is a by-product of steel making. When the fineness of slag increases, as result of increase in surface area, the hydration process would become faster than slag with normal fineness. High fineness slag’s microstructural properties and engineering properties are dinstinct from normal pozzolan material added concrete. Topics of concrete materials are changing from macroscopic engineering properties into microstructural properties. By conducting different kinds of microstructural experiments to understand the mechanism of materials reaction ,hoping by altering properties of materials can achieve target concrete performances. This research is manily using high fineness slag ,normal fineness slag to replace cement as binder material system,designing three slag replacement ratios with five ages.Conducting three types of microstructural experiments including XRD diffraction ,TG/DTA analysis, MIP and apply these three experiments’ results to compare the differences of microstructural properties between high fineness slag and normal fineness slag after the hydration process.Conducting compressive strength experiment and connect its result with microstructural experiment’s results in order to understand when high fineness slag adds into concrete how microstructural affect engineering properties