【作者】 付飞；

【导师】 叶跃忠；

【作者基本信息】 西南交通大学 ， 结构工程， 2009， 硕士

【摘要】 钢筋锈蚀是引起混凝土破坏的最主要因素,是混凝土结构面临的最主要问题之一。大多数高性能混凝土结构的破坏是由于氯离子侵入到混凝土钢筋表面,并达到一定临界浓度时引起的钢筋锈蚀所致。本文对三类高性能混凝土进行了试验研究,采用试验测试与理论分析相结合的研究方法,重点研究混凝土的氯离子渗透性,配制抗氯盐高性能混凝土。为提高混凝土的抗氯离子渗透性,本文所用混凝土均掺加矿物掺合料和化学外加剂。试验调试的三类高性能混凝土为双掺矿物混凝土、C35单一矿物防腐混凝土、C35两种矿物防腐混凝土。分别对三类混凝土进行了标准养护后力学性能和氯离子渗透性能的测试和分析,讨论其强度与渗透性的线性相关性。试验结果显示双掺矿物混凝土的力学性能和抗氯离子渗透性能均良好。C35单一矿物防腐混凝土的强度与C35双掺矿物混凝土差别不大,但抗氯离子渗透性(尤其是28d)比C35双掺矿物混凝土差,56d的抗氯离子渗透性稍好,但除粉煤灰固体防腐混凝土外,其他3种混凝土与C35、C50双掺矿物混凝土相比抗氯离子渗透性较差,不满足抗氯盐高性能混凝土的要求。C35两种矿物防腐混凝土中粉煤灰和矿渣微粉固体防腐混凝土的力学性能和抗氯离子渗透性均好于液体防腐剂混凝土和C35双掺矿物混凝土,并与C50双掺矿物混凝土接近,满足抗氯盐高性能混凝土的基本性能要求,具有较强的工程可用性。对双掺矿物混凝土进行盐溶液长期浸泡试验,分析显示双掺矿物混凝土溶液浸泡后的质量变化微小,强度抗蚀系数较高,氯离子渗透性很低,双掺矿物混凝土的抗氯盐、抗氯盐与硫酸盐复合侵蚀的性能较好。对C35、C50双掺矿物混凝土以及C35两种矿物防腐混凝土进行冻融循环的测试,混凝土冻融循环评定指标表明其抗冻性能较好,冻融循环后的氯离子渗透性很低,4种混凝土的耐冻融破坏性能和抗氯离子渗透性能均较好。本文C50双掺矿物混凝土以及C35两种矿物固体防腐混凝土的基本性能和盐溶液长期浸泡性能及冻融循环性能均良好,为抗氯盐高性能混凝土。另外本文还对氯离子腐蚀的影响因素和钢筋防腐措施进行了理论分析,提出了抗氯盐高性能混凝土的技术要求,提出京沪高铁桥梁桩基混凝土抗氯离子侵蚀的防护措施,并采用合理的现场检测和监测技术对桩基混凝土耐久性进行长期监控和研究,以保证工程质量可靠。更多还原

【Abstract】 Corrosion is the most important factor that causes the damage of reinforced concrete. And it is also one of the most important issues of concrete structure. Most destructions of the high-performance concrete structure are caused by steel corrosion due to chloride ion’s incursion into steel of concrete and its reach of certain critical concentration. In this paper, three types of high-performance concrete are studied using combination research methods of theoretical analysis and experimental study, focusing on the chloride ion penetration of concrete, to preparate the high-performance concrete that resistant chloride salts.To improve concrete’s resistance to chloride ion permeability, mineral and chemical admixtures are admixed into concrete in this paper. Three types of high performance concrete are for dual-doped mineral concrete, C35 single mineral and preservative double-doped concrete, C35 two minerals and preservative composition concrete. Test and analysis of mechanical properties and chloride ion permeability of concrete after standard conservation are carried out, and also the discussion of linear relationship of its strength and permeability. The results showed that mechanical properties and resistance to chloride ion permeability of dual-doped mineral concrete are in good condition. The strength of C35 single mineral and preservative double-doped concrete is not significant different from C35 dual-doped mineral concrete, but its resistance to chloride ion penetration (in particular,28d) is worse than that. Resistance to chloride ion penetration in 56d of C35 single mineral and preservative double-doped concrete is slightly better than 28d’s. But except fly ash and solid preservative dual-doped concrete, resistance to chloride ion penetration of other three kinds concrete are worse than C35 and C50 dual-doped mineral concrete. They don’t meet the requirements of high performance concrete resistance to chloride salts. In C35 two minerals and preservative composition concrete, mechanical properties and resistance to chloride ion penetration of the solid preservative concrete are better than the liquid preservative concrete, and so the C35 dual-doped mineral concrete, and near the C50. So it meets the basic performance requirements of high-performance concrete which resistant chloride salt, and has a strong engineering usability.In this paper, the salt solution long-term immersion test of dual-doped mineral concrete are carried out. The analysis shows that its quality changes very small, and it has the intensity factor of higher corrosion resistance, especially the chloride permeability is very low. So dual-doped mineral concrete has the high performance of resistance to chloride salts、anti-chloride and sulfate compound erosion.The freeze-thaw cycle test of three kinds are carried out.The kinds of concrete are C35, C50 dual-doped mineral concrete and C35 two minerals and preservative composition concrete.The freeze-thaw cycle assessment indicates that they have good frost, and the chloride ion penetration after freeze-thaw cycles is very low, four kinds of concrete have the high performace of resistance to freeze-thaw damage and chloride ion penetration.C50 dual-doped mineral concrete、C35 two kinds minerals and solid preservative composition concrete have good basic performance and underlying performance and long-term salt solution immersion properties and freeze-thaw cycle performance. They are the high-performance concrete which resistant chloride salts.In addition, the theoretical analysis of influence factors of chloride ion corrosion and reinforced anti-corrosion measures are made. And the technical requirements of high-performance concrete are also put forward. The protective measures on resistance to chloride ion penetration of the Beijing-Shanghai high-speed railway bridge pile of concrete are proposed. And the reasonable on-site inspection and monitoring technologies on the pile of concrete durability are used for long-term monitoring and research to ensure the project quality and reliable.更多还原