Finite element modelling approach for precast reinforced concrete beam-to-column connections under cyclic loading

Abstract

In this paper, a finite element modelling approach is developed for the analysis of the cyclic behavior of precast beamto-column connections. In particular, the modelling takes into account the compression-softening of concrete, the bond-slip effect in the critical regions and the representation of the post-cast concrete interface. A newly developed softened damage-plasticity model, which can reproduce the typical cyclic behavior of reinforced concrete, is adopted for concrete. Meanwhile, to reflect the significant bond-slip effect between concrete and reinforcement bars, the M-P stress-strain model is modified to account for the slippage by assuming the bar strain is the sum of the bar deformation and the slip, while the anchorage slip is theoretically derived and validated through benchmarking the pull-out tests. Additionally, a concrete layer between the precast concrete and the cast-in-situ concrete is incorporated to reflect the features of the interface. The proposed numerical modelling approach is validated through simulation of both interior and exterior precast beam-to-column connection tests. The validated models are subsequently employed to investigate the influences of key factors such as the compression-softening and the bond-slip effect on the analysis of the cyclic behavior of the precast beam-to-column connections. Results demonstrate that the proposed model is capable of reproducing the typical behavior of precast beam-to-column connections and can serve as an effective tool for the seismic performance analysis and investigation of design parameters of precast connections.

Experimental study on a precast beam-column joint with double grouted splice sleeves

“…Construction with the precast concrete method has gathered much attention as a substitution for conventional cast-in-situ concrete structures because of its good quality, cost effectiveness, accelerated construction speed and lower energy consumption [1][2][3][4]. Precast concrete frame structures are considered as one kind of promising precast concrete structure systems particularly suitable for the precast industry owing to their advantages including the convenience of prefabrication, standardization and erection [5]. However, the complexity and efficiency of connecting longitudinal reinforcement between precast beams and columns may impede widespread use of precast concrete frame structures.…”

Damage mechanics-based modeling approaches for cyclic analysis of precast concrete structures: A comparative study

“…According to our previous engineering practice (we used to measure the thickness in some precast specimens), the thickness of the layer is set as 10 mm. Figure 1 shows the modeling strategy (Feng et al., 2018b). Note that in this study, we did not consider pre-stressed precast concrete specimens, which requires modeling of pre-tensioning of the steel tendons.…”

“…The damage-plasticity model is used for concrete, and the strength of the concrete for the interface layer is reduced to 0.9fc to represent the weakness of the interface between pre- and postcast concrete. This value is obtained from a numerical parametric study in our previous work (Feng et al., 2018b) to investigate the influence of the layer strength. Though more detailed and elaborated approaches can be adopted, e.g.…”

“…In general, there are three major families of models, i.e. the 3D solid element-based models (Bahrami et al., 2017; Hawileh et al., 2010; Kaya and Arslan, 2009; Kulkarni et al., 2008), the 1D beam element-based models (Brunesi and Nascimbene, 2014; Feng et al., 2016, 2019b; Li et al., 2011; Valipour and Foster, 2010), and the macro-level joint element-based models (Altoontash, 2004; Bao et al., 2008; Feng et al., 2018c; Yu and Tan, 2014). The first one among the three is the most elaborate family, in which the models capture both global and local responses of the connection, such as concrete crushing and reinforcement fracturing.…”

Progressive collapse performance analysis of precast reinforced concrete structures

“…The slip s is derived on the basis of a stepped bond stress filed assumption, as shown in Figure , where the hooked bar can be simplified as a straight bar with an equivalent straight length. The bond stresses in the elastic and plastic regions of the reinforcement are assumed as constant; thus, the total slip can be expressed by the following equation according to equilibrium condition where is the strain field of the reinforcement and L d is the developed bond length.…”