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High performance concrete is an important new building materials and has broad prospects for development, due to its high resistance, high strength, high durability and is widely used in various fields of the national product. High-performance concrete resistance to chloride ion erosion studies, is an important topic of high-performance concrete as a structural material applications in the marine environment facing. In Ocean Engineering under the conditions of life of ordinary reinforced concrete structure is generally 40 to 50 years, the reinforced concrete structure of the high-performance concrete life of more than a century. This will mean substantial savings of resources, energy and funds, and also reduces environmental pollution due to premature failure of the structural members. Diffusion of chloride ions in the concrete is mainly carried out through their respective surfaces and interfaces, i.e. through the concrete in a variety of macro-cracks, or large defects, the interface of the concrete, a variety of micro-cracks and a relatively large pore (e.g. transition pore and capillary hole) diffusion. Improve the high-performance concrete around the marine environment of the subject of this center of resistance to chloride ion erosion, by analysis of the the concrete microscopic structure condition and chloride ion permeability in concrete relationship between identify concrete raw materials, mix proportion design and the concrete microscopic structure of the relationship, and performance testing and analysis. To design the C60 high-performance concrete, for example, the use of portland cement mineral admixtures superplasticizer technical route, combined with the actual marine environment, site maintenance conditions concrete reference to the standard curing samples to simulate the actual loads conditions, system. The study found that the air-entraining agent dosage is 0.01%, the superplasticizer dosage 1.2%, the concrete mixture slump nearly 20cm 28d strength of its blank sample increased by a maximum of about 1%. Under the above conditions, the cement is mineral admixtures substituted by a certain percentage the maximum substitution amounted to 40%, its strength is able to meet the design requirements. In comparison, the complex doped proportion of fly ash and slag, 25:15 best. At the same time, as mineral admixtures, pozzolanic activity, and other properties such as fineness, water demand ratio is also an important indicator of mineral admixtures. Mixture ratio design, the use of orthogonal design method, considering the impact factors of the water-cement ratio, cement, slag and fly ash, based superplasticizer, sand rate, the influencing factors were taken at three levels, calculated 9 complexes than. Among them, the value of 0.01% fixed dosage of air-entraining agent. 9 recipes turn this test from the fluidity of the concrete mixture to hardening of the concrete strength, impermeability, analysis of the impact of various factors. The effect of primary and secondary order, as well as affect the size of the pros and cons, to determine the best concrete mix ratio of water-cement ratio? .36, Cement, slag and fly ash 320 90 150kg superplasticizer 1.4% sand ratio 0.33. Also tested the impermeability of the field curing conditions loads the specimen in seawater penetration depth of less than 2cm, more than 50% of the top coat waterproof coating, the appearance of the specimen, the specimen can improve impermeability .
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