静动态荷载下改性橡胶对混凝土韧性影响研究

Influence of Modified Rubber on Toughness of Concrete under Static Load and Dynamic

为研究静、动态荷载下改性橡胶的粒径和掺量对混凝土韧性的影响规律,使用经NaOH溶液改性后的两种粒径橡胶以单掺和混掺的方式,等体积替换混凝土中0、7.5%、15%、30%的细骨料。将静态荷载下的折压比和动态荷载下的抗冲击韧性比作为韧性评价指标,通过抗压、抗折、落锤冲击试验,研究了橡胶的粒径和掺量对混凝土折压比和抗冲击韧性比的影响。试验结果表明:在静、动态荷载下,2种粒径橡胶均可有效提升混凝土的韧性。静态荷载下,小粒径橡胶表现出更优性能,掺入30%时,混凝土的折压比提升42%;动态荷载下,大粒径橡胶对混凝土抗冲击韧性比的提升更显著,掺入30%时,混凝土的抗冲击韧性比提升217.2%。为不同工程背景下橡胶混凝土的运用提供了依据。

In order to study the influence of particle-size and mixing amount of modified rubber on concrete toughness under static load and dynamic one,two kinds of rubber with different particle-size modified by NaOH solution were used to replace 0、7.5%、15%、30%of the fine aggregates in concrete by volume in the form of single and mixed mixtures,and the influence of rubber's different particle-size and content on concrete's compressive ratio and impact toughness ratio was studied by tests of the compressive,bending and drop hammer impact with the ratio of bending-compressive strength under static load and the impact toughness ratio under dynamic load as the toughness evaluating indicator.The experimental results show that:under the static load and dynamic one,two kinds of rubber with different particle-size will effectively improve the toughness of concrete.Under static load,the rubber of smaller diameter shows better performance(The bending pressure ratio of concrete increases by 42%with 30%rubber content.),while under dynamic load,the rubber of bigger diameter improves the impact toughness ratio of concrete more significantly(The impact toughness ratio of concrete increases by 217.2%with 30%rubber content.).It provides a basis for the use of rubber concrete under different engineering background.