预处理方法对压缩性能改善和故障机制的影响 循环聚合物混凝土的故障机制分析
Dongbin Lv1,2, Kainan Huang3, Wensheng Wang2
1Guangxi Fuhe Expressway Co., Ltd., Hezhou 542800, China.
Materials (Basel, Switzerland)
|May 27, 2023
概括
水泥砂的预处理可以提高回收混凝土 (RAC-C) 的性能. 这种方法提高了早期的强度,并减少了微裂纹问题,使回收聚合物成为更可行的可持续建筑材料.
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.
- 可持续建筑 可持续建筑
背景情况:
- 回收聚合物 (RA) 提供了环境效益,但由于旧的水泥砂和微裂,其性能不佳.
- 在RA上的表面缺陷会对混凝土的机械性能产生负面影响.
- 有效的预处理方法对于优化混凝土中RA利用至关重要.
研究的目的:
- 调查回收聚合物的水泥砂预处理的有效性.
- 为了增强旧水泥砂和聚合物之间的结合,补偿表面微裂纹.
- 评估不同预处理方法对回收聚合混凝土压力强度的影响.
主要方法:
- 天然聚合混凝土 (NAC) 和回收聚合混凝土 (RAC) 的制备,加湿 (RAC-W) 和水泥砂 (RAC-C) 的预处理.
- 在各种固化年龄 (7日和28日) 进行单轴压力强度测试.
- 分析断裂表面以了解故障机制.
主要成果:
- 在7天后,RAC-C表现出比RAC-W和NAC更高的压力强度.
- 在28天后,RAC-C强度超过RAC-W,但仍然低于NAC.
- 与NAC和RAC-W相比,RAC-C显著改善了早期的强度增强 (在7天内达到28天强度的85-90%),与NAC和RAC-W相比 (约. 70%). 70%). 在这个问题上.
- 故障模式从RAC-W中的聚合物-砂接口转移到RAC-C中的水泥砂粉碎.
结论:
- 水泥砂预处理显著提高了回收聚合混凝土的压力强度.
- 预处理的最佳预添加水泥含量为25%.
- 这种预处理方法提高了RA适用于实际工程应用的适用性.
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