研究多源固体废弃物基础的水泥材料的制备和收缩特性
Xu Wu1,2, Bo Li3, Dingbang Wei1,2
1Gansu Transportation Planning, Survey and Design Institute Co., Ltd., Lanzhou 730030, China.
Materials (Basel, Switzerland)
|December 23, 2023
概括
工程师们使用固体废物开发了一种新的水泥材料,以防止高速公路底层在寒冷干燥的气候下破裂. 这种材料表现出更好的强度和显著减少的收缩,为稳定粉碎石提供更好的抗裂性能.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 地质技术工程 地质技术工程
背景情况:
- 水泥稳定麦卡达姆 (CEM-SM) 基层易受冷,干旱地区的收缩裂纹的影响,原因是材料干燥收缩.
- 传统的水泥稳定材料表现出显著的干燥收缩,导致高速公路基础设施的过早裂.
研究的目的:
- 设计一个多元件固体废弃物水泥材料 (SWCM),以减轻高速公路底层的早期收缩裂.
- 评估SWCM稳定麦卡达姆 (SWCM-SM) 的抗裂特性,强度发展和抗性.
主要方法:
- 使用响应表面方法 (Box-Behnken模型) 来优化SWCM组成.
- 使用X射线衍光仪 (XRD),里埃变换红外光谱学 (FT-IR) 和热重力测量分析 (TG) 分析了协同反应机制.
- 一个专门的收缩测试系统评估了SWCM-SM的抗裂性能,强度和抗性.
主要成果:
- 最佳的SWCM成分确定为60%的渣,30%的钢渣和10%的脱硫石膏.
- 180天后,SWCM-SM表现出比CEM-SM高24.1%的压力强度和26.7%的屈曲强度.
- SWCM-SM显示,干缩应变减小了30.7%,耐性与CEM-SM相比相当.
结论:
- 钢渣和脱硫石膏增强了渣的水分,提高了粘合强度,导致早期强度低,但后来强度高.
- SWCM-SM证明了降低了水损失率,缓解了早期的微电流,并在半刚性基层中提高了早期的裂纹抵抗力.
- 开发的SWCM为在充满挑战的环境中使用持久的高速公路基层提供了一个有前途的解决方案.
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