Abstract

Owing to structural and environmental reasons, the use of pozzolans as cementitious materials in several kinds of concrete has increased in the last decade. The objectives of this experimental study were to examine the effect of weather conditions, winter and spring, on curing metakaolin-based pervious concrete; investigate the impact of various eco-friendly fine aggregates for improving the structural behaviour of this type of concrete in the above conditions; study the performance of these mixtures in the management of urban runoff; and evaluate the influence of three fine aggregates (quartz, dolomite and vermiculite) on improving the structural behaviour of various metakaolin-based pervious concrete mixtures (metakaolin was replaced by 5–25% for cement). Results indicated that: (1) in the mixtures which were cured in winter, metakaolin had no positive effect on performance of pervious concrete, but it intensified the freeze trend, so that the compressive strength of pervious concrete was significantly reduced by increasing the proportion of metakaolin, (2) in the samples cured in spring, metakaolin led to a 15% increase in the compressive strength of pervious concrete compared to the control sample, (3) the fine aggregates had desirable effects on improving the structural behaviour of pervious concrete; they reduced the freeze severity in the mixtures cured in winter and increased the compressive strength of mixtures cured in spring and (4) all the tested mixtures were able to drain 10–40 cm of runoff in a short time period.

摘要

由于结构和环境原因，在过去十年中，火山灰在几种混凝土中作为胶凝材料的使用有所增加。本实验研究的目的是检查冬季和春季天气条件对偏高岭土基透水混凝土固化的影响；在上述条件下，研究各种环保细骨料对改善此类混凝土结构性能的影响；研究这些混合物在城市径流管理中的作用；并评估三种细骨料（石英、白云石和蛭石）对改善各种偏高岭土基透水混凝土混合物的结构行为的影响（水泥用 5-25% 的偏高岭土代替）。结果表明：（1）在冬季固化的混合物中，偏高岭土对透水混凝土性能无积极影响，但加剧了冻结趋势，使透水混凝土的抗压强度随着偏高岭土比例的增加而显着降低，（2）在春季养护的样品中，偏高岭土导致与对照样品相比，透水混凝土的抗压强度提高了 15%，(3) 细骨料对改善透水混凝土的结构性能具有理想的效果；他们降低了冬季固化混合物的冻结程度，提高了春季固化混合物的抗压强度，并且 (4) 所有测试的混合物都能够在短时间内排出 10-40 厘米的径流。因此，通过增加偏高岭土的比例，透水混凝土的抗压强度显着降低，（2）在春季养护的样品中，偏高岭土导致透水混凝土的抗压强度比对照样品增加 15%，（3 ) 细骨料对改善透水混凝土的结构性能具有理想的效果；他们降低了冬季固化混合物的冻结程度，提高了春季固化混合物的抗压强度，并且 (4) 所有测试的混合物都能够在短时间内排出 10-40 厘米的径流。因此，通过增加偏高岭土的比例，透水混凝土的抗压强度显着降低，（2）在春季养护的样品中，偏高岭土导致透水混凝土的抗压强度比对照样品增加 15%，（3 ) 细骨料对改善透水混凝土的结构性能具有理想的效果；他们降低了冬季固化混合物的冻结程度，提高了春季固化混合物的抗压强度，并且 (4) 所有测试的混合物都能够在短时间内排出 10-40 厘米的径流。(3)细骨料对改善透水混凝土结构性能有较好的效果；他们降低了冬季固化混合物的冻结程度，提高了春季固化混合物的抗压强度，并且 (4) 所有测试的混合物都能够在短时间内排出 10-40 厘米的径流。(3)细骨料对改善透水混凝土结构性能有较好的效果；他们降低了冬季固化混合物的冻结程度，提高了春季固化混合物的抗压强度，并且 (4) 所有测试的混合物都能够在短时间内排出 10-40 厘米的径流。