低取代率再生骨料混凝土性能及其改善措施
发布时间：2019-03-22 11:36
【摘要】：再生骨料技术对于节约资源、保护环境和实现建筑业的可持续发展具有重要意义,也是国内研究人员关注的热点。目前,国内关于再生混凝土的研究尚未成熟,且大部分是针对再生骨料高取代率下混凝土性能的研究,其理论结果难以系统地指导实际生产与工程应用。本文在国内外研究成果的基础上,立足于国内再生骨料制备工艺及生产现状,系统研究了再生骨料在低取代率下再生混凝土的强度和耐久性能,对再生骨料的实际应用具有重要的理论意义和实践价值。 本文以水胶比、再生粗骨料取代率、再生细骨料取代率、矿物掺合料掺量为变化参数,进行了混凝土抗压强度、轴心抗压强度、抗氯离子渗透性能、抗冻性能、抗碳化性能试验。并分析了不同水胶比、再生骨料不同取代率和矿物掺合料不同掺量下混凝土强度和耐久性的变化规律。针对再生粗骨料自身缺陷,采用盐酸和PVA聚合物两种改善措施分别对再生粗骨料进行改性,对混凝土抗压强度、轴心抗压强度、抗氯离子渗透、抗冻性能、抗碳化性能进行测定,分析了盐酸和PVA聚合物对再生粗骨料界面改性后混凝土强度和耐久性的改善效果。基于再生混凝土早期抗裂性能较差,试验研究了聚丙烯纤维对再生混凝土早期抗裂的改善效果。 相比普通混凝土,再生粗骨料取代率在30%以内时,低水胶比(0.40-0.48)时再生混凝土强度略有降低,耐久性指标均有一定幅度的提高,高水胶比(0.56-0.60)时再生混凝土强度略有提高；再生粗骨料取代率超过30%时,强度和耐久性能有所降低。再生粗骨料混凝土中掺入粉煤灰,混凝土抗氯离子渗透性能明显提高,抗冻性能变化不明显,抗碳化性能呈下降趋势；粉煤灰与矿粉各掺15%时,混凝土抗氯离子渗透性能和抗冻性能均显著提高,但其抗压强度相对较低。盐酸改性方法对混凝土强度和耐久性均有一定改善；PVA聚合物改性后抗冻性有所降低,其它性能指标均有所改善；聚丙烯纤维能够有效改善再生混凝土的早期抗裂性能。再生细骨料取代率在30%以内时,混凝土强度和耐久性均优于普通混凝土。再生细骨料混凝土中不建议使用矿物掺合料。
[Abstract]:The technology of recycled aggregate plays an important role in saving resources, protecting the environment and realizing the sustainable development of the construction industry. At present, the domestic research on recycled concrete has not been mature, and most of it is the research on the performance of the concrete at the high substitution rate of recycled aggregate, and the theoretical results are difficult to guide the actual production and engineering application systematically. On the basis of domestic and foreign research results, based on the preparation technology and production status of recycled aggregate in China, the strength and durability of recycled aggregate at low substitution rate are studied, and the practical application of recycled aggregate is of great theoretical and practical value. In this paper, the concrete compressive strength, axial compressive strength, anti-chloride penetration resistance, anti-freezing performance and anti-carbonization performance of the concrete were tested with the ratio of water-to-cement ratio, the replacement rate of the regenerated coarse aggregate, the substitution rate of the regenerated fine aggregate and the variation of the content of the mineral admixture. The change rules of concrete strength and durability under different ratio of water and cement, different substitution rate of recycled aggregate and different content of mineral admixture are also analyzed. in that light of the defect of the recycled coarse aggregate, two improvement measures of hydrochloric acid and PVA polymer are adopted to modify the recycled coarse aggregate, and the compressive strength, the axial compression strength, the chloride ion penetration, the anti-freezing property and the anti-carbonization property of the concrete are measured, The effect of hydrochloric acid and PVA polymer on the strength and durability of recycled coarse aggregate is analyzed. The effect of polypropylene fiber on the early crack resistance of recycled concrete was studied based on the poor early crack resistance of recycled concrete. When the substitution rate of the recycled coarse aggregate is within 30% compared with the common concrete, the strength of the recycled concrete is slightly reduced when the ratio of the low water-to-water ratio (0.40-0.48) is within 30%, and the durability index has a certain amplitude, and the strength of the recycled concrete is slightly higher when the ratio of the high water-to-water ratio (0.56-0.60) is higher (0.56-0.60). It is possible to improve the strength and durability when the substitution rate of the recycled coarse aggregate exceeds 30%. in that method, the fly ash is incorporated into the recycled coarse aggregate concrete, the anti-chloride ion penetration property of the concrete is obviously improved, the change of the anti-freezing property is not obvious, and the anti-carbonization property is in a downward trend; and when the fly ash and the mineral powder are mixed with each other for 15%, the anti-chloride ion penetration property and the anti-freezing property of the concrete are both obvious to improve, but its compressive strength The modified method has a certain improvement on the strength and the durability of the concrete; the anti-freezing property of the PVA polymer is reduced, and the other performance indexes are improved; and the polypropylene fiber can effectively improve the early-stage resistance of the recycled concrete. When the substitution rate of the recycled fine aggregate is within 30%, the strength and durability of the concrete are superior to that of the common Concrete is not recommended in recycled fine aggregate concrete
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU528
本文编号：2445553
[Abstract]:The technology of recycled aggregate plays an important role in saving resources, protecting the environment and realizing the sustainable development of the construction industry. At present, the domestic research on recycled concrete has not been mature, and most of it is the research on the performance of the concrete at the high substitution rate of recycled aggregate, and the theoretical results are difficult to guide the actual production and engineering application systematically. On the basis of domestic and foreign research results, based on the preparation technology and production status of recycled aggregate in China, the strength and durability of recycled aggregate at low substitution rate are studied, and the practical application of recycled aggregate is of great theoretical and practical value. In this paper, the concrete compressive strength, axial compressive strength, anti-chloride penetration resistance, anti-freezing performance and anti-carbonization performance of the concrete were tested with the ratio of water-to-cement ratio, the replacement rate of the regenerated coarse aggregate, the substitution rate of the regenerated fine aggregate and the variation of the content of the mineral admixture. The change rules of concrete strength and durability under different ratio of water and cement, different substitution rate of recycled aggregate and different content of mineral admixture are also analyzed. in that light of the defect of the recycled coarse aggregate, two improvement measures of hydrochloric acid and PVA polymer are adopted to modify the recycled coarse aggregate, and the compressive strength, the axial compression strength, the chloride ion penetration, the anti-freezing property and the anti-carbonization property of the concrete are measured, The effect of hydrochloric acid and PVA polymer on the strength and durability of recycled coarse aggregate is analyzed. The effect of polypropylene fiber on the early crack resistance of recycled concrete was studied based on the poor early crack resistance of recycled concrete. When the substitution rate of the recycled coarse aggregate is within 30% compared with the common concrete, the strength of the recycled concrete is slightly reduced when the ratio of the low water-to-water ratio (0.40-0.48) is within 30%, and the durability index has a certain amplitude, and the strength of the recycled concrete is slightly higher when the ratio of the high water-to-water ratio (0.56-0.60) is higher (0.56-0.60). It is possible to improve the strength and durability when the substitution rate of the recycled coarse aggregate exceeds 30%. in that method, the fly ash is incorporated into the recycled coarse aggregate concrete, the anti-chloride ion penetration property of the concrete is obviously improved, the change of the anti-freezing property is not obvious, and the anti-carbonization property is in a downward trend; and when the fly ash and the mineral powder are mixed with each other for 15%, the anti-chloride ion penetration property and the anti-freezing property of the concrete are both obvious to improve, but its compressive strength The modified method has a certain improvement on the strength and the durability of the concrete; the anti-freezing property of the PVA polymer is reduced, and the other performance indexes are improved; and the polypropylene fiber can effectively improve the early-stage resistance of the recycled concrete. When the substitution rate of the recycled fine aggregate is within 30%, the strength and durability of the concrete are superior to that of the common Concrete is not recommended in recycled fine aggregate concrete
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU528
【参考文献】
相关期刊论文 前10条
1 王建伟;姚文杰;;混凝土的早期收缩机理与开裂条件研究[J];低温建筑技术;2006年03期
2 陈建良;倪竹萍;;强化处理改善再生骨料混凝土性能试验[J];低温建筑技术;2011年02期
3 范小平;;再生骨料混凝土的开发与研究[J];福建建材;2006年04期
4 赵俊,钟世云,王小冬;建筑垃圾的减量化与资源化[J];粉煤灰;2001年02期
5 田俊峰,潘德强,赵尚传;海工高性能混凝土抗氯离子侵蚀耐久寿命预测[J];中国港湾建设;2002年02期
6 刘数华;饶美娟;;再生骨料混凝土变形性能和耐久性能研究综述[J];公路;2009年10期
7 崔正龙;北徎政文;田中礼治;;固体废弃物再生骨料混凝土的耐久性试验研究[J];硅酸盐通报;2009年05期
8 张雷顺,王娟,黄秋风,邓宇;再生混凝土抗冻耐久性试验研究[J];工业建筑;2005年09期
9 杨建军;李俊毅;雷周;张鹏;王娜;王一宝;;混凝土电通量的影响因素分析[J];中国港湾建设;2012年04期
10 秦荷成;;聚丙烯纤维对再生混凝土早期抗裂性能影响的试验研究[J];广西水利水电;2013年03期
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