This research is focused on identifying the porosity in concrete manufactured with air-cooled blast furnace slag as coarse aggregate and analyzing its potential use as sound absorption material. Six concrete mixes were manufactured by using three types of aggregate with different particle size distributions and consequently, diverse porosity in the matrix. Acoustic characteristics and mechanical properties of concrete were determined. In a complementary study, an X-ray computed tomography analysis has been carried out in order to establish a connection between the pore structure and its corresponding acoustic and mechanical behavior. Mixes composed of 80% wt of slag with particle sizes between 5 and 10 mm having higher porosity and a better acoustic absorption than those using natural coarse aggregate of the same particle size, although their mechanical properties are lower. A combination of three layers each 4 cm thick containing the larger slag particle sizes in the noise incident face of the concrete, followed by the medium slag particle size and finally, the finest material, presented excellent sound absorption properties, which allowed all the slag to be recycled.

中文翻译：

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风冷高炉矿渣粗骨料透水性混凝土中X射线计算机断层扫描的多孔结构和吸声性能

这项研究的重点是确定由空气冷却的高炉矿渣制成的混凝土的孔隙率是粗骨料，并分析其作为吸声材料的潜在用途。通过使用三种具有不同粒径分布并因此在基质中具有不同孔隙率的集料来生产六种混凝土混合物。确定了混凝土的声学特性和力学性能。在一项补充研究中，已进行了X射线计算机断层扫描分析，以建立孔结构与其相应的声学和机械性能之间的联系。由80％wt的炉渣组成的，粒径在5到10 mm之间的混合物具有比使用相同粒径的天然粗骨料的更高的孔隙率和更好的吸声性，尽管它们的机械性能较低。每层4厘米厚的三层组合，在混凝土的噪声入射面中含有较大的炉渣颗粒，其次是中度的炉渣颗粒，最后是最细的材料，具有出色的吸音性能，使所有炉渣都能被回收。