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以西宁火车站地下配套建设工程为依托,结合盐湖卤水环境中混凝土的腐蚀类型和腐蚀机理,依据场地实际结构物所面临的腐蚀环境,从设计与施工两方面给出了混凝土抗腐蚀设计的总体思路.即选用高性能混凝土、提高保护层厚度,并依据各构造部位的自身特点采取对应的附加抗腐蚀手段,来提高混凝土结构的耐久性和稳定性.最后通过开展混凝土抗腐蚀试验,验证了工程所用高性能混凝土在盐湖卤水环境中拥有极佳的抗腐蚀能力. 相似文献
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基于损伤演化方程的混凝土寿命预测方法 总被引:1,自引:0,他引:1
基于混凝土的冻融或腐蚀损伤演化方程,提出了一套预测混凝土结构使用寿命的基本方法与理论体系;用单一冻融因素作用下的大量试验数据验证了混凝土的损伤演化方程;通过专门设计的盐湖卤水腐蚀单一因素和(干湿循环+盐湖卤水腐蚀)双重因素、3.5%质量浓度的NaCl盐冻试验,研究了青海盐湖钾肥和北京城市立交桥主体结构混凝土的使用寿命预测问题.结果表明:青海盐湖钾肥工程不宜采用普通混凝土和高强混凝土;C60引气高性能混凝土在盐冻作用下满足北京城市立交桥50年的使用要求. 相似文献
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硫酸盐对混凝土腐蚀研究 总被引:5,自引:1,他引:4
对普通混凝土和高强混凝土在5.0%Na2SO4(质量分数,下同)、10%MgSO4溶液以及青海盐湖卤水溶液中的损伤失效规律、特点进行研究。结果表明:混凝土在Na2SO4溶液中浸烘循环腐蚀破坏,SO42-导致混凝土产生膨胀性破坏;其损伤劣化包括3个阶段:初始劣化段、性能改善段和性能劣化段。混凝土在MgSO4溶液、青海盐湖卤水中浸烘循环腐蚀损伤,腐蚀溶液中的SO42-和Mg2+共同作用导致混凝土产生剥落型破坏;其相对动弹性模量和重量随腐蚀时间先下降,后稳定,最后加速下降。此外,用SEM、能谱和XRD分析了混凝土在硫酸盐腐蚀作用下的腐蚀产物。 相似文献
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数字混凝土——混凝土技术发展的新方向 总被引:1,自引:0,他引:1
从数字化技术发展出发,论述了现代混凝土的技术进展,提出并探讨了数字混凝土的概念、实质、任务,从几个典型方面分析了数字混凝土建设中已经取得的重要进展,如高性能混凝土配合比设计方法、复合超塑化剂配方设计方法、预拌混凝土搅拌运输车的GPS系统的实时在线监测,论述了数字混凝土技术在混凝土质量控制和标准化建设中的作用,说明了数字混凝土建设的必要性和战略意义。 相似文献
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本文首次提出了分箱钢一混凝土组合箱梁方案,介绍了该梁的特点与优势。并针对长沙市东风路高架桥工程的方案初选阶段的方案进行比较计算,得到了相关结论,为今后对于该新方案的运用提供了良好前景。 相似文献
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《Building Research & Information》2013,41(5)
Following the collapse of roof beams at a school in London, a nationwide survey of the use and condition of high-alumina cement concrete in public buildings had to be undertaken in the UK. The findings of extensive research work and site tests have now been reported. 相似文献
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《Construction and Building Materials》2010,24(9):1608-1615
This work presents a statistical study on the variability of the mechanical properties of hardened self-compacting concrete, including the compressive strength, splitting tensile strength and modulus of elasticity. The comparison of the experimental results with those derived from several codes and recommendations allows evaluating if the hardened behaviour of self-compacting concrete can be appropriately predicted by the existing formulations. The variables analyzed include the maximum size aggregate, paste and gravel content. Results from the analyzed self-compacting concretes presented variability measures in the same range than the expected for conventional vibrated concrete, with all the results within a confidence level of 95%. From several formulations for conventional concrete considered in this study, it was observed that a safe estimation of the modulus of elasticity can be obtained from the value of compressive strength; with lower strength self-compacting concretes presenting higher safety margins. However, most codes overestimate the material tensile strength. 相似文献
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本刊讯9月19日,第六届水泥与混凝土国际会议暨CANMET/ACI混凝土技术可持续发展国际会议在西安隆重召开。会议由中国硅酸盐学会、加拿大矿产资源部混凝土可持续发展技术中心及美国混凝土学会联合主办,中国自然科学基金会、中国水泥协会等10家单位协办。中外300余名专家学者与会, 相似文献
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P.F.G. Banfill 《Building and Environment》1980,15(3):181-190
The possible use of Mersey silt as a fine aggregate for concrete has been investigated. Sound concrete with compressive strength up to 45 N mm?2 has been made. However, the cement content required for typical mixes is higher than with conventional sands and there is no overall cost saving. Current British Standard limits for silt content of aggregates have been examined critically in the light of available data and it is recommended that the requirement for material finer than 75 μm be eased to 5% of the total aggregate weight. 相似文献