## 4 Discussion and Conclusions  
In the process of structural construction, it is a research hotspot to intelligently predict the mechanical parameters of the structure and then predict the safety performance of the structure according to the design parameters. This study proposes an intelligent prediction method of structural construction safety based on the BP neural network. Based on the exploration of the theoretical method, it is applied in the construction process of string beam. The feasibility of this research method is verified by comparing the predicted and measured values of mechanical parameters. In the research process of structural construction safety intelligent analysis method, the following main findings were obtained.  
(1) Based on the construction characteristics of prestressed steel structure, the correlation mechanism of structural safety performance parameters is established. Driven by the BP neural network, the structural design parameters and mechanical parameters are integrated.  
(2) In the process of structural safety prediction, the virtual-real interaction is carried out by DTs. The simulation data are extracted in the twin model. The fusion mechanism of DTs and BP neural network is formed for the intelligent prediction of structural construction safety. Supported by each other, a high robustness structural construction safety performance prediction model is established.  
The construction conditions are set in the digital twin model, and the design parameters and mechanical parameters of the structure are extracted to provide data samples for the neural network. The mechanical parameters of the intelligent prediction structure formed by the BP neural network are used to analyze its safety state. In the construction process, a structural safety assessment is carried out according to the changes of mechanical parameters of different structural forms. This research method improves the intelligent degree of structural construction safety prediction. At the same time, the integration of mechanical parameters and specification constraints provides a reference for the control of  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Mechanical Parameter** & **Specific Limits** \\ \hline \hline \
\begin{tabular}{c} Perpendicular displacement \\ Cable stress \\ \end{tabular} &
\begin{tabular}{c} less than 1/250 of structural span \\ less than 1/2.5 of allowable stress \\ \end{tabular} \\ \end{tabular}
\end{table}
Table 2: Limits of mechanical parameters of structures.  
Figure 11: Comparison between the model output cable stress and measured value (part of the samples).  
the construction safety of real structures. Combining mechanical parameters with design parameters to find the key factors that affect the structural safety performance is the next research focus. Therefore, based on the experience and lessons of this study, future research is needed to improve the intelligence level of the construction process by considering more realistic conditions.  
Conceptualization, H.Z.; methodology, H.Z.; software, H.Z.; validation, H.Z. and Y.W.; writing--original draft preparation, H.Z.; writing--review and editing. H.Z.; project administration, H.Z.; funding acquisition, H.Z. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to the confidentiality.  
The authors would like to thank South China University of Technology, Guangzhou, China, for their support throughout the research project.  
The authors declare no conflict of interest. The authors declare no conflict of interest. The funders had no role in the study's design; in the collection, analyses or interpretation of data; in the writing of the manuscript or in the decision to publish the results.