【作者】 高策；

【导师】 叶跃忠；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2007， 硕士

【摘要】 再生混凝土是指采用破碎后的废弃混凝土作为骨料制备得到的混凝土，废弃混凝土破碎后得到的骨料称为再生骨料。随着社会经济的飞速发展，使用再生混凝土可以有效地避免环境污染和资源浪费，是建筑行业实现可持续发展的重要途径。本文首先通过正交试验设计配制了C25、C40两个强度等级的混凝土，主要考察再生骨料取代率、高效减水剂掺量、粉煤灰掺量等三个因素分别在不同水平下的混凝土抗压强度和抗拉强度。认为在混凝土设计等级较低情况下随再生骨料取代率增加，混凝土强度会降低，但在设计强度等级较高时，再生骨料取代率对强度的影响并不明显；与普通混凝土类似，使用粉煤灰会降低再生混凝土早期强度。另外，试验中还通过扫描电镜照片对再生混凝土与普通混凝土的内部结构进行了比较。砌块、路缘石、道路基层是再生混凝土技术的最初应用对象，无疑这为再生混凝土技术的推广迈开了重要的第一步。但是，根据目前研究结果和发展水平来看，再生混凝土技术的应用不应仅限于此，建筑的承重构件或结构如梁、柱等都应该被纳入视野。本文进行了一片再生混凝土梁与两片普通混凝土梁的对比试验。试验结果显示：再生混凝土梁的加荷——破坏的过程与普通混凝土梁是类似的；基本符合平截面假定；再生混凝土梁极限承载力与普通混凝土梁相当；在相同荷载水平下，再生混凝土梁挠度与普通混凝土梁差别不大。另外试验还对现行规范对再生混凝土梁的适用性进行了讨论。更多还原

【Abstract】 Recycled concrete is a kind of concrete which is made of demolished concrete debris as aggregates. With the rapid development of economy, the usage of this technology will avoid pollution of environment and nature resource waste. It’s an important approach to achieve continuable development in construction industry.In this paper, the author designed two kind of concrete with different strength grade. The intent is investigating the influence of replacement ratio of recycled aggregate; high range water reducing agent and fly ash on concrete strength. According to the experiment result, replacement ratio of recycled aggregate affect the concrete compressive and tensile strength only in low strength grades obviously and fly ash could reduce the early strength. Scanning electron microscope pictures are screened and analyzed.Recycled concrete has been applied in concrete block and road base, it is an important step of popularizing this technology, and however it would be applied in much more significant components, for instance, beam and column. In the paper, one recycled concrete beam and two normal concrete beams was cast. The author tries to compare the difference between them. As a result, in the loading process, cross sections of recycled concrete beam still keep planes; the ultimate moment of recycled concrete beam is close to the normal concrete beam; under same loads, there aren’t visible differences between their deflections. In addition, the specification’s applicability to recycled concrete beam is discussed.更多还原