用于制备具有空心微球的自压缩轻质混凝土的条件
Aleksandr Sergeevich Inozemtcev1, Sergey Dmitrievich Epikhin1
1Scientific and Educational Center Nanomaterials and Nanotechnologies, National Research Moscow State University of Civil Engineering, 129337 Moscow, Russia.
Materials (Basel, Switzerland)
|December 9, 2023
概括
这项研究证明了使用空心微球成功生产自压缩轻质混凝土. 研究确定了实现具有理想机械性质的稳定,均混合物的关键参数.
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.
- 混凝土技术 混凝土技术
背景情况:
- 使用轻质聚合物生产自压缩混凝土,由于混合物分离而面临挑战.
- 空洞微球为制造低密度,自压缩混凝土提供了一个潜在的解决方案.
研究的目的:
- 研究使用空洞微球生产自压缩轻质混凝土的可行性.
- 确定混合物设计参数与自压缩轻质混凝土的特性之间的关系.
主要方法:
- 通过测量震动前后的扩散直径 (Dsp,1 → Dsp,2) 来评估自我紧缩.
- 根据水与水泥的比率 (W/C) 和增塑剂度 (CPl) 确定了移动性的回归方程,奥斯瓦尔德-韦尔系数,密度和强度.
- 评估了石英砂分散 (Sp/Sf比) 对混合物特性的影响.
主要成果:
- 使用空心微球证实了重量轻的混凝土的自压缩能力,密度为1450±25 kg/m3.
- 对于 W/C ≤0.6 和 CPl ≤1.0% 的确定的同质性极限.
- 观察到的密度在1403-1485 kg/m3之间,屈曲强度 (Rfl) 在3.34-5.90 MPa之间,压力强度 (Rcom) 在29.6-45.7 MPa之间.
结论:
- 使用空心微球,可以实现具有低密度的自压缩轻质混凝土.
- 最佳的混合设计参数 (W/C和CPl) 对于均性和所需的物理机械性能至关重要.
- 在测试范围内,石英砂分散对自我紧缩和机械性能的影响微不足道.
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