Numerical investigation on the behaviour of the high-strength ring strengthened dowel connection under vertical load

To improve the bearing resistance of individual pavement connections at joint surface, an innovative high-strength ring strengthened dowel connection was developed. A comprehensive finite element analysis (FEA) was then conducted to investigate the ultimate load of this novel connection and the compressive stress development of concrete. Parameters including the compressive strength of high-strength concrete (HSC), the thickness and the length of the high-strength ring were analysed. The FEA results indicated that the ultimate load of the dowel connection was enhanced as the thickness and compressive strength of the high-strength ring increased. Due to the expanded contact area created by the high-strength ring, compressive stress created in normal-strength concrete was reduced, thereby delaying the initiation of localised concrete crushing. Furthermore, since the crushing failure primarily concentrated at the joint surface, the length of the high-strength rings was optimised to 25 mm to fully utilise the excellent compressive behaviour of HSC. Finally, based on the obtained FEA data, analytical models were derived to predict the maximum compressive stress of concrete under the service limit state and the ultimate load of the dowel connection embedded into concrete under the ultimate limit state.