Rapid Repair of Concrete Roads using Calcium Aluminate Cement Based Mortar in Winter Conditions

Calcium aluminate based mortars have been widely used for fast setting repair applications. This article will present the laboratory work that was conducted to repair an existing concrete road in Istanbul. The main damage mechanism was both abrasion and frost damage; the maximum time that the road can be closed to traffic is only 6 hours. As the repair was going to be performed in the winter, the desired final compressive strength of the mortar has to be minimum 10 MPa in 4 hours at 5°C. The developed repair mortar consists of calcium aluminate cement, Portland cement and various chemical additives. Lithium carbonate was used as an accelerator and citric acid was used as a plasticiser and set controller. Also a lignosulfonate based superplasticiser was used in order to achieve the desired flowability. Micro silica is added to control the rheology and to prevent the conversion reactions of calcium aluminate cement. First trials performed by CIMSA Cement Research and Application Centre laboratories. After the laboratory trials field application will be performed in ?stanbul by ?ston.