## 1 Introduction  
Achieving an effective shear connection between the various materials involved is the primary challenge in steel-concrete composite construction. Early studies in this field primarily utilized experimental techniques, particularly push-out tests, to evaluate shear performance [1, 2, 3, 4]. Among the various types of shear connectors, the headed stud connector quickly gained the most attention due to its simple design and construction efficiency [5; 6]. Scientific experiments and comprehensive research [7; 8; 9] have provided valuable insights into shear connections employing headed studs, influencing their integration into applications and design standards such as Eurocode [10]. However, ongoing laboratory investigations and numerical analyses continue to enhance our knowledge of the actual behavior of these connections. Numerical methods are becoming increasingly important in the analysis of composite structures. It has become common practice in structural analysis to create numerical models that are validated by a small number of laboratory tests rather than conducting extensive laboratory experiments. Although three-dimensional finite element (FE) models offer many benefits, some configurations may lack accuracy due to their complexity and the wide range of possible parameters. Consequently, validation through laboratory experiments, as demonstrated in [11; 12], has become an essential and widely accepted best practice; it offers both economic and sustainability benefits and additionally enables numerical models to support further scientific research, as shown in [13; 14]. Previous investigations have revealed several parameters that influence the behavior of steel-concrete composite action [15; 16]. The load-displacement performance of the connection is influenced by the shank diameter, height, and tensile strength of the studs, in addition to the compressive strength and elastic modulus of the concrete. According to [PERSON] and [PERSON] [17], the connector's height to diameter (hd) ratio must be at least 4 in order to obtain the best shear performance. Improving the shear capacity of stud connectors in steel-concrete composite connection requires this minimum ratio. [PERSON] and [PERSON] [18] performed a series of push-out tests to examine the behavior of stud shear connectors in both normal and high strength concrete. It has been demonstrated that the strength of the concrete has a considerable effect on the shear capacity of the studs. It was observed that the addition of transverse reinforcement had a minimal effect in high-strength concrete, while it exhibited more noticeable effects in normal-strength concrete. Based on these observations, a design formula has been developed that incorporates the interaction between the studs and the surrounding concrete. Numerous studies have examined this area more recently, with a particular emphasis on the importance of concrete properties in the steel-concrete composite connection. [PERSON] et al. [19] carried out an extensive study on the effect of ultra-high-performance concrete (UHPC) on composite action, examining various height of shear studs, focused on the reduced thickness of UHPC bridge deck slabs, ranging from 35 to 60 mm. In such configurations, the h/d ratio can be less than 4. The study concluded that the shear performance of a stud is influenced by the mechanical properties of both the concrete and the stud. For a fixed stud strength, an increase in concrete strength results in a higher shear force, bringing closer to its maximum shear capacity. Although high-strength concrete improves the utilization of stud shear capacity, it simultaneously decreases the total slip of the shear connection. Therefore, it is crucial to achieve an optimal balance between the strengths of the concrete and studs in order to maximize the load-displacement performance of the connection. [PERSON] et al. [20] examined the numerical and experimental behavior of steel-concrete composite connections utilizing UHPC.