## 1 Introduction
These features indicate that the FDEM may be used to simulate the demolition of reinforced concrete buildings. There are numerous research publications available to simulate the fracturing of solid structure with reinforcement based on the FDEM. Most publications on reinforcement in RC structures using the FDEM have incorporated the linear edge reinforcement model into the finite concrete model via the embedded method [13; 14; 15; 16; 17; 18; 19; 20; 21]. In other words, the reinforcement model is conceptually separated by interfaces of the solid finite elements corresponding to the concrete (hereafter, concrete elements) part and remains fixed within the concrete elements. The reinforcement model can be deformed only through the deformation of the concrete element. Previous research [13; 14; 15; 16; 17; 18; 19] have actively developed the reinforcement model by integrating FDEM and solid elements containing rebar, i.e., embedded rebar elements, and interface elements connecting the rebars, i.e., rebar joint elements. In the embedded rebar finite elements, a linear-elastic model is used, whereas the constitutive model in the rebar joint elements is applied by classifying the before and after the occurrence of a crack in the concrete. When no concrete separation occurs, the penalty function assures the continuity of the rebar finite components in this model [13]. After concrete cracking, on the other hand, the rebar model in the joint element adopts a path-dependent mechanical model [22]. The developed rebar model was validated through simulations of several simple experimental tests, including three- or four-point flexural loading and tension loading under monotonous or cyclic static and dynamic loading conditions. Good agreement between the FDEM and experimental results was obtained for the simulation of the fracture processes in the RC structures such as RC walls, Prothyron structures and exterior RC beam-column joints. Meanwhile, in [20; 21], a reinforcement model for rock structure reinforcement via linear rock support (i.e., rockbolts, dowels, cables, etc.) was developed in the 1D reinforcement model. The reinforcement model includes a reinforcement finite element and reinforcement joint. In these works, the axial stress of the reinforcement finite element is calculated under the assumption of linear elasticity. The axial stress of the reinforcement joint is computed by selecting between the linear elasticity and elasto-plastic model, and tangential stress of the reinforcement joint is calculated by the linear elasticity model. Performance of the 1D support model was compared to the explicit reinforcement bars model (i.e., FDEM rebar model) by simulating the pull-out load and double shear test demonstrating excellent agreement. The results of laboratory double shear tests [23] were also compared to numerical simulations and were found to be in good agreement in terms of the damage of the concrete and the rebar deformation. Recently, the so-called two-node bolt element model with a spring-slider shear connector has been further developed into the GPGPU-based FDEM code in order to rapidly simulate the reinforcement of rock mass around underground excavations by fully-ground rockbolts [24]. In the work, numerical instability caused by specific intersections between triangular mesh and rockbolts is resolved by adopting only the equivalent length of the bolt finite element without separation by the finite rock element. The spring-slider shear connection is also used to simulate the existence of a grout annulus between the rockbolt and the surrounding rock. To validate rockbolt logic, the pull-out tests were simulated, and rock bolting in underground excavations was successfully reproduced. However, existing research are mostly limited to two-dimensional (2D) study. Although the previous work [25] described the fracturing of the three-dimensional RC structure model, a detailed description was not provided in the paper. Therefore, this work attempts to expand to the analysis of 3D reinforced structures.