# Safety Performance Evaluation of Ultra-High-Performance Concrete Semi-Assembled Barrier
## 6 Conclusions  
In this study, a new semi-assembled barrier based on UHPC was developed, and a finite element simulation of the collision process of the newly semi-assembled barrier was performed using the nonlinear explicit dynamics software LS-DYNA. A full-scale collision test of a real vehicle was conducted and its results were compared with the numerical simulation results. The following conclusions can be drawn:  
1. The collision force between the three models and the barrier was extracted and analyzed, and the average collision force peak of 25 ms was compared with the theoretical collision force, which has high consistency. It is considered that the peak value of the 25 ms collision force in this simulation can be used as the basis for static load design.
2. A collision simulation of a new semi-assembled barrier was performed. It was found that the barrier provided good guidance and reduced damage to the occupant.
3. After collision, the barrier did not show overall damage, which does not affect the continued use of the barrier. The maximum lateral dynamic deformation value of the barrier was 0 and the UHPC shell and the NC were in synergistic force during the collision.
4. Whether numerical simulation or real vehicle crash test, the ORA and OIV were less than the standard allowable values, suggesting that the new semi-assembled barrier had a good buffering function for the vehicle.
5. The collision test results for the real vehicles were in good agreement with the simulation results by LS-DYNA software. This suggests that finite element simulation can predict real outcomes to some extent, which can serve as a basis for full-scale collision tests, potentially reducing unnecessary investments in such tests. The research findings can offer theoretical support for promoting the widespread adoption of this new type of barrier.  
Figure 16: Displacement in the simulation.  
In view of the limitations of the numerical model described in the previous section, it is not yet possible to comprehensively simulate failures, such as tire shedding and tire blowout, that may occur during actual collisions. Therefore, subsequent studies will focus on further optimization of the vehicle numerical model, while the safety performance under different working conditions will be considered more systematically to ensure that the simulation results are more reliable and realistic.  
Methodology, L.L.; Software, W.X.; Formal analysis, W.X.; Investigation, L.L. and L.S.; Resources, R.H.; Data curation, Z.L.; Writing--review & editing, Z.L.; Visualization, L.S.; Funding acquisition, R.H. All authors have read and agreed to the published version of the manuscript.  
The work was also supported by Fundamental Research Program of Shanxi Province (Shanxi Transportation Holdings Group Co., Ltd.) (No. 202303011221002); by Key Laboratory of Highway Construction & Maintenance Technology in Loess Region, Ministry of Transport, PRC (KLTLR-Y23-4); by 2023 Shanxi Graduate Student Innovation Project (2023 KY252).  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
Author [PERSON] and [PERSON] were employed by the company \"Shanxi Transportation Technology R&D Co., Ltd.\" and \"Shanxi Transportation Research Institute Group Co., Ltd.\". The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The sponsors had no role in the design, execution, interpretation, or writing of the study.