Influence of Variable Stress Ratios on Carbon-Reinforced Concrete Under Biaxial Tensile Loading
摘要
Concrete pavements show damage from traffic loads and water-dissolved pollutants such as chlorides and alkalis at the joints after only a short period of use. To repair concrete pavements and extend their service life, carbon-reinforced concrete (CRC) is suitable as a joint covering layer. In addition to traffic loads, the CRC covering layer is primarily exposed to environmental influences such as temperature changes over time. If the temperature drops from zero into the low temperature range, the joints in the concrete pavement open and the CRC covering layer is subjected to tensile stress. The carbon reinforcement enables the formation of cracks due to tension above the joints with small crack spacing and small crack widths. Biaxial tensile stresses arise above intersecting joints. The stress ratio of the biaxial tensile load in the CRC covering layer varies depending on the spacing of the transverse and longitudinal joints in the concrete pavement. In the present study, the load-bearing and deformation behavior of the CRC covering layer were analyzed, taking into account the influences of different stress ratios. For this purpose, biaxial tensile tests were carried out on slab specimens with a two-layer carbon grid. The results allow for a configuration of the CRC covering layer under consideration of different tensile stress ratios.