Study on the Shear Resistance Performance of Grouped Stud Connectors

In order to further investigate the grouped stud effect on the force properties of stud connectors, based on the premise that the correctness of the finite element simulation method, in this paper, a finite element model of grouped stud connectors was developed, and the grouped stud effect and its sensitivity factors were analyzed in order to validate the recommended formula for calculating the shear capacity of grouped stud connectors. Results show that the number of grouped stud rows and stud row spacing have a significant influence on the grouped stud effect, and the unevenness coefficient of grouped stud force is negatively correlated with the number of grouped stud rows as well as the grouped stud row spacing. Grouped stud connectors with commonly used concrete grades greater than C50 and height-to-diameter ratios of greater than 4 in steel-concrete composite structural bridges are insensitive to changes in the concrete strength grades and the length of the studs. The direction of force transmission for grouped stud changes with the change in loading angle and the unevenness coefficient of force for the grouped stud will therefore be reduced. By comparing the results of the 62 existing groups of grouped stud connectors push-out tests, the mean of the tested to calculated value ratio was found to be 1.12, the variance was 0.023, the dispersion was small, and it was shown that the recommended formula has a high degree of accuracy. The results of this paper can be used as a theoretical basis for the study of the shear stress performance of grouped stud connectors.