| 摘要: |
利用混凝土搅拌站废水作为拌和水，制备了超硫酸盐水泥混凝土，研究了其力学和抗冻性能，并通过扫描电镜、X射线衍射仪及低场核磁共振观察了混凝土的微观形貌、物相组成及孔隙特征.结果表明：全废水超硫酸盐水泥混凝土早期抗压强度较低，后期抗压强度发展较快；水胶比0.41的全废水超硫酸盐水泥混凝土掺入80%矿渣后，其28 d抗压强度可达48.6 MPa，矿渣中的玻璃体被废水中的OH-溶解，生成钙矾石和水化硅酸钙，从而使混凝土微观形貌致密，孔隙率低至2.5%，100次冻融后混凝土的孔隙率增加至3.5%，T2![]() ![]() 驰豫谱曲线明显向有害孔偏移，试件中出现裂缝与断层，强度和抗冻性能降低. |
| 关键词: 全废水 超硫酸盐水泥混凝土 力学性能 抗冻性能 机理分析 |
| DOI：10.3969/j.issn.1007-9629.2024.10.008 |
| 分类号:TU528.3 |
| 基金项目:宁夏市重点研发计划项目（2022BEE03001）；宁夏市自然科学基金资助项目（2023AAC03040）；国家自然科学基金资助项目（52368037，51968060）；宁夏市青年拔尖人才支持计划项目（2022118）；宁夏市一流学科建设计划项目（NXYLXK2021A03） |
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| Mechanical Property and Frost Resistance of Full Wastewater Supersulfated Cement Concrete |
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WU Chenjie1, KE Long1, WANG Dezhi1,2,3,4, ZHANG Haiwei1, ZHAO Yan1
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1.School of Civil and Hydraulic Engineering， Ningxia University， Yinchuan 750021， China;2.Engineering Technology Research Center of Water-Saving and Water Resource Regulation in Ningxia， Ningxia University， Yinchuan 750021， China;3.Engineering Research Center for Efficient Utilization of Modern Agricultural Water Resources in Arid Regions， Ministry of Education， Ningxia University， Yinchuan 750021， China;4.Engineering Technology Research Center of Earthquake Protection and Disaster Mitigation in Civil Engineering in Ningxia， Ningxia University， Yinchuan 750021， China
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| Abstract: |
Supersulfated cement concrete was prepared using wastewater from a concrete mixing plant as mixing water， its mechanical property and frost resistance were studied. The microstructure， phase composition and pore characteristics of concrete were observed by scanning electron microscopy， X-ray diffraction and low field nuclear magnetic resonance. The results show that early compressive strength of full wastewater supersulfated cement concrete is low， but it develops rapidly in the later stage. The 28 d compressive strength of full wastewater supersulfated cement concrete with a water binder ratio of 0.41 mixed with 80% slag can reach 48.6 MPa. The glass in slag is dissolves by OH- in wastewater to form ettringite and hydrated calcium silicate， so that the concrete microstructure is dense and the porosity is as low as 2.5%. After 100 times of freezing-thawing， the porosity of concrete increases to 3.5%， and T2![]() ![]() relaxation spectrum curve obviously shifts to harmful pores. Cracks and faults appeare in the specimens， and the strength and frost resistance decrease. |
| Key words: full wastewater supersulfated cement concrete mechanical property frost resistance mechanism analysis |
