Study on the bending deformation properties of microcracked R-ECC road–bridge link slabs

A novel road-bridge link slab utilizing rubberized engineered cementitious composites (R-ECC) has been proposed for fully jointless bridges (FJBs). Preliminary research has shown that R-ECC road-bridge link slabs possess superior deformation absorption capacity, tensile strength, and crack control capabilities. However, micro-cracks developed on the surface of these slabs due to seasonal temperature fluctuations. While R-ECCs demonstrate improved bending ability compared to conventional ECCs, they exhibit lower compressive strength. Further research is necessary to investigate the crack development and bending deflection of microcracked R-ECC road-bridge link slabs under vehicle loads, which will help determine the suitability of R-ECCs for this application. The microcracked R-ECC slab has a great crack control capacity, and the rebound deflection measured in the experiment is less than the allowable value, indicating that the microcracked R-ECC slab meets the durability and strength standard. A sensitivity parameter finite element analysis was conducted considering the effects of slab thickness and equivalent elasticity modulus of the foundation on the R-ECC road-bridge link slab. Two evaluation indexes 'C_t' and 'C_e' are proposed to evaluate the performance and construction cost of the R-ECC slab. To improve performance and minimize construction costs, a design thickness of 180 mm and an equivalent elasticity modulus of the foundation of 800 MPa were recommended for the R-ECC road-bridge link slab.