The numerical simulation for UHPC-RC composite beam based on lattice model

The ultra-high performance concrete-reinforced concrete(UHPC-RC) composite beam leverages the superior material attributes of both concrete and UHPC, offering enhanced performance in structures susceptible to erosion or cracking. This paper explores the shear behavior of UHPC-RC composite beams through an integrated experimental and numerical simulation approach. The study commences by establishing and validating meso-structures for concrete and UHPC based on lattice principle and material test. It then introduces an experimental setup with five UHPC-RC specimens to scrutinize the effects of UHPC layer, longitudinal reinforcement, and specimen dimensions on shear resistance. Numerical simulations utilizing Finite Element (FE) model and lattice models are executed, with both models demonstrating their capability to accurately predict the bearing capacity of beam and to simulate their mechanical behavior, cracking patterns, and failure processes. This paper innovatively employs a discrete lattice model to overcome the limitations of traditional continuum models in depicting UHPC post-cracking actions, offering a detailed analysis at a finer scale. This study contributes to the body of knowledge by providing a perspective on the failure mechanisms of UHPC-RC composite structures and providing a solid foundation for future research in this field.