Numerical Investigation of Performance of Continuous Composite Girders with UHPC slab at Hogging Moment

Abstract

This paper intends to investigate the behavior of continuous composite girders with of ultra-high-performance concrete (UHPC) slab at hogging moment zone utilizing the nonlinear finite element (FE) modeling. A nonlinear three-dimensional FE model of the continuous composite girder was developed utilizing the commercial software ABAQUS. The model considers both material and geometric nonlinearities. Behavior of normal concrete (NC) and UHPC was modeled utilizing damage plasticity model. Tied, normal friction behavior, embedded contacts were used to simulate the interfacial zones between contacted elements. Four different models were developed and validated with experimental results. The verified model showed satisfactory behavior and is capable of predicting the loading history for continuous composite girders. The model can capture the modes of failure either in normal concrete slab at sagging moment zone or delaminating of UHPC layer at hogging moment zone. A parametric study was carried out to investigate the effect of length of UHPC slab at hogging moment zone on the behavior of the continuous composite girders. The findings of the parametric study showed that the length of UHPC slab slightly affects the ultimate capacity, yielding load, and stiffness of the composite girders. However, significant enhancement in cracking loads was obtained as increasing the length of UHPC slab.