循環利用營建材料產生的固體廢棄材料，在世界各地受到了相當大的關注。為了要提供固體廢棄物有新的利用方向，本研究探討使用混合飛灰(FA)與稻殼灰(RHA)材料利用地聚合技術，製作的鹼激發膠體(AAB)以及利用緻密配比法(DMDA)生產綠建築磚。鹼激發膠體試體方面，探討固液比(S/L)、養護溫度、稻殼灰含量以及氫氧化鈉溶液的濃度對於試體抗壓強度發展的影響。而在綠建築磚方面，探討成型壓力、漿量、以及未研磨稻殼灰(URHA)含量對於硬固磚工程表現上的影響。另外，使用X光繞射分析(XRD)以及傅立葉轉換紅外光譜分析，進行觀察鹼激發膠體以及建築磚的微觀性質。掃描式電子顯微鏡(SEM)搭配能量散佈光譜儀(EDS)用來分析樣品的表面的型態與組成。本研究發現了液固比、養護溫度、稻殼灰含量以及氫氧化鈉的濃度對於鹼激發膠體均有很明顯的影響。其中觀察到最高強度的鹼激發膠體採用固液比2.6、養護溫度60℃、氫氧化鈉溶液濃度10M以及稻殼灰含量35%所製作的樣品。此外，所有綠建築磚的試體均展現出良好的性能。使用最多到30%天然砂體積比的稻殼灰取代，並且以成型壓力35MPa、養護溫度約在35℃，並且相對溼度控制在50%情況下，所生產的綠建築磚性能十分良好，而且這一類型的磚符合目前在越南實心建築磚的標準。此外，微結構分析結果顯示了鹼激發膠體與磚的主要晶相皆為石英、莫萊石以及方英石，另外還存在了少量的沸石相。本研究的結果支持了使用飛灰與稻殼灰製造鹼激發膠體與綠建築磚的可行性。

Using solid waste materials in the production of construction materials has received considerable attention across the world. The present study investigates the possibility of using a blended fly ash (FA) and rice husk ash (RHA) in the production alkali-activated binder (AAB) using geopolymerization technology and of green construction bricks through the application of densified mixture design algorithm (DMDA) in order to provide a new use for solid waste materials. For the AAB samples, the effects of the solid-to-liquid (S/L) ratio, curing temperature, RHA content, and concentration of sodium hydroxide (NaOH) solution on the compressive strength development of the samples were investigated. For the green construction bricks, the effects of forming pressure, paste amount, and unground rice husk ash (URHA) content on engineering performance of the hardened bricks were studied. In addition, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to examine the microstructural properties of both the AAB and brick samples. Scanning electron microscopy (SEM) coupled with energy dispersive spectrometer (EDS) was used to characterize the samples surface morphologies and compositions. The present study found that the S/L ratio, the curing temperature, the RHA content, and the concentration of NaOH had significant effects on the properties of the AAB samples. The highest strength obtained from the AAB samples that were prepared at an S/L ratio of 2.6, a curing temperature of 60ºC, a NaOH concentration of 10 M, and an RHA content of 35%. Besides, all of the brick samples demonstrated excellent properties. Bricks with up to 30% of the natural sand volume replaced by URHA performed well at a forming pressure of 35 MPa, a curing temperature of around 35ºC, and a relative humidity of around 50%, which indicate that bricks of this type conform well to the current Vietnamese standards for solid construction bricks. Further, microstructural analyses showed that the major crystalline phases presented in the resultant AAB and brick samples were quartz, mullite, and cristobalite with the additional presence of minor zeolite phases. The results of the present study support the use of FA and RHA in the production of AAB and green construction bricks.

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