循環式流體化床鍋爐燃燒過程中，加入石灰石脫硫後大量產生之副產物CFB副產石灰(含粉狀、粒狀)，為避免出廠後產生揚塵及方便搬運，故以浸水24 hr作為處理，使其形成水化副產石灰並堆放於戶外堆置場存放。因長期以來未能有效將其利用及去化，大量堆放下所引致堆置用地、處理費用與環保等相關問題，故而考慮將水化副產石灰用來改良軟弱土壤或作為掩埋場不透水襯裡層。 本研究將水化副產石灰搭配水庫淤泥，在不同比例下探討各配比混合料之夯實特性、加州載重比與水力傳導度等工程性質，同時評估混合料在浸水環境下之潛在膨脹行為。試驗結果顯示，水庫淤泥與水化副產石灰混合後，承載能力明顯提升但孔隙比相對增加；然而膨脹潛能試驗中，由於水化副產石灰含有大量石膏，且水庫淤泥本身也具有膨脹性，受材料特性影響而具有吸水膨脹及水化反應之行為，使混合料試體膨脹量增加，但水化副產石灰用量增加，有減緩膨脹量之效果。最後透過水化程度試驗進一步探討水化副產石灰膨脹行為，研判混合料之膨脹與其水化未完成有關。 ;In the Circulating fluidized bed (CFB) boiler combustion process, a lot of limestone was added for desulfurization and byproducts generated from CFB include fly ash and bed ash. In order for dust mitigation and easy moving, the ashes were soaked in water for 24 hrs to form Hydrated Circulating Fluidized Bed (HCFB) ash and was then placed on the sites for outdoor storage. This study aims at using HCFB ash as stabilizer for soft soil and as impervious lining materials for landfills. In this study, different proportions of HCFB ash were mixed with an reservoir clay to explore the compaction characteristics, the California load ratio (CBR), and the permeability of the mixtures. In addition, the potential expansion behavior of the mixtures was studied too. The results show that adding HCFB ash to the reservoir clay can enhance the load bearing capacity, but with an increase in void ratio. However, in the expansion test, it was found that the mixtures exhibited higher swelling potential. This is because the large amounts of gypsum containing in HCFB ash is creating extra spaces around swelling particles of the reservoir clay, thus allowing the mixture to swell more. Finally, a degree of hydration test was conducted to further explore the swelling behavior of HCFB ash.