本研究探討使用 F 級飛灰和 爐石粉(GGBFS) 取代部份水泥，及水膠比為0.485及砂率為2.75之水泥砂漿之工程性質與健性，實驗變量試驗變數包括一個對照試體、四種GGBFS 替代品（5%、10%、15% 和20%）、四種粉煤灰替代品（5%、10%、15% 和20%）以及三種混合GGBFS 和飛灰(5%、10% 和 15%)，坍流度用以評估新拌性能，而硬化性能包括抗壓強度、超聲波脈衝速度 (UPV)、導熱性、重量損失和微觀結構分析，包括掃描電子顯微鏡 (SEM) 和 X 射線衍射 (XRD)。
結果顯示控制組坍流度測試結果為216 mm，而添加5%水淬高爐石粉後會使坍流度降至173.75 mm，添加5%燃煤飛灰則會使坍流度降至182.75 mm，並且當同時添加5%水淬高爐石粉和燃煤飛灰時坍流度僅降至204 mm；控制組抗壓強度隨齡期增加(從7天至56天)持續增加，並在第56天觀察到之最高抗壓強度為62.53 MPa，而添加20%水淬高爐石粉後，測得抗壓強度為50.68 MPa，添加20%燃煤飛灰抗壓強度為60.64 MPa，此外，當同時添加5%水淬高爐石粉和燃煤飛灰時，在56天所測最高抗壓強度為52.36 MPa；對照不同組別的超聲波脈衝速度值，在密閉環境和開放環境養護條件下均為增加。在密閉環境條件下，56天齡期記錄超聲波峰值為4155.33 m/s；在不同溫度中用硫酸鹽養護的試體熱導率結果皆為下降，另外，與常溫相比，在密閉環境以硫酸鹽浸泡對混凝土的抗壓強度產生較大的影響。
在密閉養護(以硫酸鹽浸泡）下對樣品進行SEM和XRD分析，結果顯示試體中皆存在鈣礬石，而在開放養護（空氣養護）下的試體皆含有二氧化矽。鈣礬石和二氧化矽具有填充混凝土孔隙的能力，從而減少孔隙率並提高試體的相對密度。一般來說，試體密度越高抗壓強度則越高。

This study investigated the engineering properties and soundness of hardened mortar through the partial replacement of cement with class F fly ash and ground granulated blast-furnace slag (GGBFS), in which a water-to-binding ratio of 0.485 and a sand ratio of 2.75 were used. The experimental variables included one control specimen, four substitutions with GGBFS (at 5%, 10%, 15%, and 20%), four substitutions with fly ash (at 5%, 10%, 15%, and 20%), and three substitutions with blended mixture of GGBFS and fly ash (at 5%, 10%, and 15%). The slump flow was assessed for fresh properties, while the hardened properties included the compressive strength, ultrasonic pulse velocity (UPV), thermal conductivity, weight loss, and microstructural analysis, including scanning electron microscopy (SEM) and X-ray Diffraction (XRD).
The results indicated that the slump flow of the control group was 216 mm. Adding 5% GGBFS reduced the slump flow to 173.75 mm. Similarly, adding 5% coal-fired fly ash resulted in a slump flow reduction to 182.75 mm. The combination of 5% GGBFS and coal-fired fly ash led to a decrease in slump flow to 204 mm. The compressive strength test results of the control group increased with age (from 7 days to 56 days). The strength continued to increase, reaching the highest compressive strength of 62.53 MPa on the 56th day. When adding 20% coal-fired fly ash, the measured compressive strength was 50.68 MPa. For 20% coal-fired fly ash, the compressive strength reached 60.64 MPa. Moreover, when 5% GGBFS and coal-fired fly ash were added simultaneously, the highest measured compressive strength on the 56th day was 52.36 MPa. Comparing the ultrasonic pulse velocity values of different groups, it was observed that they increased under both closed and open environment curing conditions. In airtight conditions, the peak ultrasonic wave recorded at age of 56 days was 4155.33 m/s. The thermal conductivity of the specimens cured with sulfate at different temperatures decreased. Additionally, immersion with sulfate in a closed environment had a greater impact on the concrete's compressive strength than at room temperature.
Samples were subjected to SEM and XRD analysis under airtight curing (soaked in sulfate). The results showed that ettringite was presented in all samples. Conversely, all samples subjected to open curing (air curing) contained silicon dioxide. Both ettringite and silica had the ability to fill the concrete's pores, thereby reducing porosity and increasing the relative density of the specimen. In general, the higher specimen density correlated with the higher compressive strength.

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