THE EFFECTS OF FORMWORK SURFACE PROPERTIES ON CONCRETE CARBONATION

The aim of this study is to investigate the effects of formwork surface properties on concrete carbonation. Seven concrete wall formworks with different surface properties, Scotch pine, Black poplar, sheet iron and four plywoods, were constructed in this study. Tree out of four wall plywood formworks were prepared with drainage channels and holes. The formwork surfaces consisting of drainage channels and holes were covered with different geotextile liners. The concrete were casted into all prepared wall formworks, which were removed after 28 days that the sample blocks were prepared. The blocks were kept under atmospheric conditions for six years. After that, the depths of carbonation were determined using the taken core samples of all blocks. In addition, the pH values were investigated on the concrete powder samples that were obtained from different depth levels of the concrete blocks. The results indicated that formworks including both drainage and liners gave lower carbonation compared to the other formworks. The lowest carbonation was observed with the formwork that was covered with SB-20 geotextile. On the other hand, the highest carbonation was found with the sheet iron formwork.