Numerical Analysis of a Novel Prefabricated Concrete Beam with Double-Grouted Couplers under Static Loading

This paper provides a nonlinear finite element (FE) investigation of a novel prefabricated beam with double-grouted coupler splices to complement the experimental work and promote its application. FE model considering the surface-to-surface contact behaviour between the prefabricated concrete and grouting mortar is constructed and validated using test data. The validated model is subsequently utilised to conduct a parametric analysis of the most influential factors comprising the diameter and eccentricity of linking rebar and connecting length. Results indicate that the fewer the grouted couplers and the shorter the coupler length, the smaller the effect on the damage pattern and stress distribution of the beam. As the tensile linking rebar diameter increases by 2 mm and 4 mm, the ultimate stress of the linking rebar decreases by 33.4% and 44.0%, respectively, and the maximal crack width in the linking region drops by 85.9% and 97.7%, respectively. Increasing the tension linking rebar diameter significantly reduces the unfavourable influence of linking rebar eccentricity on the linking zone crack width. A decrease in the filler length helps lessen the crack width in the connecting region. Based on the present study, several recommendations for practical engineering use of the developed beam are also presented.