| 摘要: |
| 以采石场废弃白云岩粉为前驱体，成功制备了具有优异机械性能的白云岩碱激发净浆，研究了不同养护温度对其抗压强度、断裂韧性和断裂能的影响，探究了养护温度的微观影响机制.结果表明：废弃白云岩粉可在碱激发剂的作用下发生去白云石化反应和离子交联反应，形成具有优异力学性能的白云岩碱激发净浆；白云岩碱激发净浆的抗压强度和断裂韧性在养护温度为150 ℃时达到最大，而其断裂能随养护温度变化较小；在不同养护温度下，白云岩碱激发净浆内部不同发育形态的碳酸钙晶须是其抗压强度和断裂韧性变化的主要影响因素. |
| 关键词: 碱激发净浆 白云岩 抗压强度 断裂韧性 断裂能 |
| DOI：10.3969/j.issn.1007-9629.2022.07.003 |
| 分类号:TU525.9 |
| 基金项目:国家自然科学基金资助项目（51878314， 52178288） |
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| Effect of Curing Temperature on Fracture Performance of Dolomite-Based Alkali-Activated Paste |
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LIN Weiqing1, ZHOU Fangyuan1, LUO Wenjun2, ZHOU Lemu3, YOU Lingyun1
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1.School of Civil and Hydraulic Engineering， Huazhong University of Science and Technology， Wuhan 430070， China;2.Faculty of Materials Science and Chemistry， China University of Geosciences（Wuhan）， Wuhan 430070， China;3.Hubei Road and Bridge Group Co.， Ltd.， Wuhan 430070， China
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| Abstract: |
| Dolomite-based alkali-activated paste with excellent mechanical properties was successfully prepared with quarry waste dolomite powder as precursor. The effects of different curing temperatures on the compressive strength， fracture toughness and fracture energy of the pastes were studied， and the microscopic influence mechanism of curing temperature was investigated. The results show that the waste dolomite powder can undergo dedolomitization and ion cross-linking reaction under the effect of the alkali activator to form dolomite alkali-activated paste with excellent mechanical properties. The compressive strength and fracture toughness of alkali-activated dolomite paste reach the maximum value at curing temperature of 150 ℃， while the fracture energy varies little with the change of the curing temperature. Under different curing temperatures， the calcium carbonate whisker with different forms in the dolomite-based alkali-activated paste is the main factor affecting the changes of compressive strength and fracture toughness. |
| Key words: alkali-activated paste dolomite compressive strength fracture toughness fracture energy |
