RESEARCH ON DEFORMATION OF MORTAR WITH NOVEL EXPANSIVE AGENT
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摘要: 基于对富镁尾矿资源化利用途径的开发,制备新型膨胀材料,对新型膨胀材料与掺合料对水泥砂浆自由变形、干缩变形和限制变形性能的影响展开研究。结果表明:升高水化温度对水泥砂浆前期膨胀速率的增加比较明显,对水化后期影响较小;膨胀材料和粉煤灰双掺可较好地抑制水泥砂浆的干缩,使干缩在90 d就趋于稳定;养护温度对水泥砂浆限制膨胀率影响较大,使用该膨胀材料时要注意温控;拟合曲线表明,该新型膨胀材料具有持续稳定的膨胀性能,不存在无限膨胀和回缩现象。Abstract: A novel expansive agent was prepared by using magnetite and dolomite tailings through certain process.The deformation properties of mortar mixed with expansive agent and fly ash were investigated. Results showed that atthe early age, the expansion speed increased obviously with the increase of hydration temperature, but at the later agethere was no obvious effect on the increase of expansion speed. The dry shrinkage of mortar can be seriouslysuppressed by both expansive agents and fly ash, and dry shrinkage tended stable at the age of 90 d. The temperaturewas an important factor for the restricted expansion of mortar, so the temperature should be strictly controlled whenusing this expansive agent. The regression analysis curve showed that the expansion properties of this expansive agentwere stable through the whole course of hydration, and there was no excessive expansion and retraction.
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Key words:
- expansive agent /
- concrete /
- mortar /
- deformation /
- dry shrinkage
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