Effects of Short Stud Arrangement on Flexural Behavior of Ultra-High Performance Concrete Composite Bridge Decks

Abstract:

In order to investigate the effects of short stud arrangement on flexural behavior of steel-ultra-high performance concrete （UHPC） composite bridge decks， flexural tests of two full-scale segmental bridge deck specimens with a stud spacing of 200 and 300 mm respectively were performed， and a finite element parametric analysis based on the UHPC plastic damage model was conducted. The test results show that， as the stud spacing of partially-composited bridge decks increases from 200 mm to 300 mm， when the UHPC cracking reaches up to 0.05 mm in width， the corresponding load increases by 12.5 %. The main contributor is the weakening of the steel-UHPC combination effect. The average tensile strain of the UHPC is 1 878×10^-6 as the cracking reaches 0.10 mm in width， accounting for about 59 % of the material ultimate tensile strain. The parametric analysis shows that as the stud spacing increases from 100 mm to 400 mm， the elastic bending stiffness decreases by 14.1 %， while the cracking load increases by 84.2 %. The increase of the short stud spacing makes the partially-composited bridge deck tend to be more mechanical-economical， but attention should be paid to the fatigue damage of the stud because of the too large stud spacing.