【作者】 蒋胜晖；

【导师】 沈蒲生；

【作者基本信息】 湖南大学 ， 结构工程， 2010， 硕士

【摘要】 随着混凝土结构早期失效问题的突出和恶劣环境下工作的混凝土结构大量出现,传统的混凝土显得越来越不能满足现代建筑结构的要求。二十世纪九十年代出现的高性能混凝土将对混凝土强度、耐久性、工作性的要求提高到了同样的高度,已成为了混凝土材料与结构发展的主要方向。本文在前人研究的基础上,分析了高性能混凝土的实现途径和性能影响因素;通过正交试验设计了不同配比的粉煤灰高性能混凝土实验,研究了高性能混凝土的性能增长机理;将未确知测度理论引到混凝土强度预测中,建立了高性能混凝土强度预测的未确知测度方法,并结合工程实例探讨了高性能混凝土结构性能的施工保障技术。主要创新点如下:⒈以水胶比、砂率、粉煤灰掺量和高效减水剂掺量为主要影响因素,通过正交实验设计了不同配比的粉煤灰高性能混凝土试验,研究了粉煤灰对混凝土性能的影响。研究表明,影响粉煤灰高性能混凝土坍落度的因素顺序为:水胶比→粉煤灰掺量→高效减水剂→砂率;影响粉煤灰高性能混凝土28d抗压强度的因素顺序为:高效减水剂→水胶比→粉煤灰掺量→砂率。并确定了60MPa粉煤灰高性能混凝土的可选配比。⒉高性能混凝土性能影响很多而且存在大量未确知性。本文首次将未确知测度理论应用混凝土强度预测中。在对混凝土强度预测方法和未确知理论进行研究的基础上,以水胶比、粉煤灰掺量、高效减水剂掺量和砂率,将混凝土28d抗压强度作为输出指标建立了考虑多因素的混凝强度预测的未确知测度方法。⒊混凝土结构的性能不仅与材料有关,还与施工、养护的质量有关。本文结合工程实例,研究了高性能混凝土施工中材料计量、搅拌、运输、浇筑、振捣、养护等各工序对混凝土性能的影响,建立了高性能混凝结构的性能保障体系。更多还原

【Abstract】 With the early failures and poor working conditions of concrete structures, the traditional concrete has become increasingly unable to meet the requirements of modern buildings. The high-performance concrete, which occurred in nineties of twentieth century, puts the requirement to the concrete’s strength, durability, workability to the same height, which has become the main direction of development of concrete materials and structures.Based on previous studies, the realization ways of high performance concrete and its factors were analyzed; by orthogonal experimental design with different proportions of high performance concrete experiment, the growth mechanism of high performance concrete was studied; unascertained measure theory was adopted to create a high-performance concrete strength unascertained measure method, and combined practical project structure the technologies of supporting of high performance concrete structure properties were put forward in this thesis.The main innovations are as follows:1. Set the water-cement ratio, sand ratio, fly ash and superplasticizer dosage of the main factors, The influence of fly ash on concrete properties was studied after different proportions of fly ash concrete tests which were designed by the orthogonal experimental. The results show that the order of factors affected the performance of fly ash concrete is water-cement ratio→the ratio of fly ash→sand ratio→superplasticizer; the order of factors affected 28d compressive strength of fly ash high performance concrete is water-cement ratio→superplasticizer→sand ratio→the ratio of fly ash. And the optional ratio for high performance fly ash concrete which compressive strength is up to 60MPa was put up.2. There are a lot of unascertained fators affected the performance of concrete and there are. The unascertained measure theory in the field of concrete strength prediction has been applied first. After analyzed the methods of concrete strength prediction and the unascertained theory, set the water-cement ratio, fly ash, superplasticizer dosage and sand ratio as input parameters and 28d compressive strength of concrete as output, the strength prediction method of unascertained measure, which can consider multi-factors, was established.3. Not only the materials, but also the quality of construction, maintenance have influence to the performance of concrete structures. Combining with the practice a high-performance, the influence of, mixing, transport, pouring, vibrating, curing and other processes in construction on properties of high performance concrete structures were studied and the security system of concrete structures was established.更多还原