C80矿渣高强混凝土的试验研究

【作者】 张华英；

【导师】 张德思；

【作者基本信息】 西北工业大学 ， 材料学， 2004， 硕士

【摘要】 高强高性能混凝土是20世纪80年代后才出现的新型建筑材料。由于高强高性能混凝土具有高强度、高耐久性、高工作性等特性，用其代替传统的混凝土结构物和建造在严酷环境中的特殊结构，具有显著的经济效益。国外有人预言，21世纪将大量应用100MPa以上的结构混凝土。 作者通过对混凝土材料的组成和结构进行宏观、微观和细观三个层次的系统分析发现，混凝土材料的力学性能和耐久性主要取决于其微观的组织构成；在组成混凝土材料的三相(硬化水泥浆体、集料和硬化水泥浆体-集料界面过渡区)中，界面过渡区是其中最薄弱的一环。因此，要提高混凝土材料的强度和耐久性等宏观性能，就必须减少其内部的微观缺陷，特别是要改善界面过渡区的结构，提高界面过渡区的密实性和黏结力，从而提高混凝土的强度和耐久性。 本文采取“普通硅酸盐水泥+矿物细掺料+高效减水剂”技术路线和“净浆裹石”搅拌工艺，采用42.5R普通硅酸盐水泥配制出抗压强度为85MPa、坍落度为120mm的高强高性能混凝土，并给出了C80高强高性能混凝土的推荐配合比。 本试验采用正交设计方案，并利用SPSS统计分析软件对试验数据进行了系统的统计分析。分析了水胶比、硅灰掺量、矿渣掺量和高效减水剂掺量对高强高性能混凝土强度的影响，并根据综合平衡法得出本文所采用的原材料体系的最优配合比。同时，在其他因素不变的情况下，对高强高性能混凝土28天抗压强度与胶水比的关系进行线性回归。试验结果表明：在混凝土中同时掺入硅灰和矿渣可以产生复合火山灰效应和微集料填充效应；“净浆裹石”搅拌工艺可以大大改善界面过渡区结构，从而提高混凝土的强度。更多还原

【Abstract】 High strength & high performance concrete came into being as a new construction material in 1980’s. For its desired properties including high strength, long durability and good workability, it has been shown remarkably economic in replacing traditional concrete structure and building special structure using in the aggressive environment. It has been prophesied that the concrete with strength over 100MPa will be widely used.Through systematically analyzing the composition and structure of concrete from three levels of macroscopic, microcosmic and ultra- microcosmic, the author of this paper found that the mechanical properties and durability of concrete depended on mainly its composition and structure. The interface, which is one of three composition of concrete (hardened cement paste, aggregate and interface), is the most weak zone in concrete. Therefore, the key to improve strength and durability of the concrete is to decrease flaws of concrete, especially to meliorate the structure of interface, which will improve the compactness and cohesion of interface, thus improve the strength and durability of the concrete.By using the method of adding ordinary Portland cement with fine mineral admixture and super plasticizer and the mixing process of Stone Enveloped with Cement, the high strength & high performance concrete with strength of 85MPa and slump of 120mm are produced, and the method of producing C80 high strength & high performance concrete are recommended in this paper.This experiment is carried out complying with orthogonal test-schema, then the author carry on systematic statistical analysis to the test data with SPSS. It analyzes the effect of water/binder ratio, percentage of silica fume and slag and super plasticizer on the strength of the high strength & high performance concrete. And then, the optimum of mix proportions of every composition is acquired according to the comprehensiveequilibration theory. Simultaneously, regression analysis is carried out between the 28d compressive strength of HSC and the binder/water ratio with no variation of other factors. The result of the experiments shows that the effects of compound pozzolanic and micro-aggregate have been produced when silica fume and slag were added into concrete together. And the Stone Enveloped with Cement can meliorate distinctly the structure of the transition zone of interface, thus the strength of concrete is improved.更多还原