A study for practical use of the concrete using natural resources "Shirasu" as an aggregate

1.材料数据库对鹿儿岛县37个地采集的白拉苏混凝土骨料的性能和特点进行了调查，并根据调查结果编制了白拉苏混凝土集料数据库和白拉苏集料细度模数图。2.试验方法针对白拉苏集料的比重、吸水率和细度模数的测试，提出了考虑白拉苏集料性能的新的试验方法。3.根据试验结果，对白拉苏混凝土的制备、配合比设计、拌和、浇筑、养护和检验等方面提出了新的试验方法对石拉苏混凝土进行了长期耐久性试验，特别是中和性、抗氯离子渗透性、抗硫酸盐侵蚀和ASR的活性。5.在上述试验的基础上，进行了温泉环境下桥梁结构基础混凝土和预制PC梁混凝土的实际试验。此外，还考察了自密实混凝土和硬化灰材料的一些特殊适用性。

1.Material DatabaseFor the Shirasu samples collected from 37 places in Kagoshima prefecture, properties and characteristics of Shirasu as an aggregate for concrete were investigated, and according to the results, a data base and a Shirasu-Map, were prepured.2.Test MethodsAs the tests of specific gravity, water absorption, and fineness modulus for shirasu aggretate, new test methods considering the propery of Shirasu were proposed.3.Construction"Recommendation for design and construction of concrete using Shirasu aggregate" including preparation, mixdesign, mixing, placing, curing, and inspection, for Shirasu concrete was specified, according to the experimental results, in both labratry and construction site.4.DurabilityExporsure tests of Shirasu conrete were performed, to examine its long term durability, especially concerning to neutralization, penetration of chloride ion, sulfate-resistance, and reactibity of ASR.5.Practical UseDepending on above examinations, some practical trials, such as concrete in the foundation of a bridge structure constructed in hot spring environment and concrete for precast PC girder,were realized. Addition to that, some special applicability, for such as self-compacting concrete and hardened coal-ash material, were examined.