## 3 Method and Materials
### Construction of Digital Monitoring System for Asphalt Concrete Pavement Construction
#### 3.3.2 Composition of the Digital Monitoring System  
After the data management system acquires key data monitored during the production and construction of each subsystem (see Table 4 for monitoring indicators), the data are correlated with the indicators related to the production quality of the project, and the data of each system are linked in real time. For example, the data information linkage of the batches of mixed materials transported by each train is realized, and the position information of the pile number corresponding to the paving of the mixed materials transported by each train is also realized. The system links the data information of the mixed material transported by each transport vehicle, the loading and unloading time of the vehicle, the driving data information, the paving and compaction data information, and realizes the integration of various businesses. The system can also comprehensively and centrally monitor key data and has the characteristic function of a real-time alarm. It can view data and alarms in various ways, and realize the implementation quality control of the entire project. The schematic diagram of data linkage is shown in Figure 3.  
Asphalt Material Production Monitoring System  
The quality state of the asphalt mixture in the production process directly determines the quality of the mixture [39]. Moreover, during the \"13 th Five-Year Plan\" period, China attaches great importance to building a resource-saving and environment-friendly society, and it is necessary to significantly reduce energy consumption and carbon dioxide emissions. Carbon emissions and energy consumption in the production of asphalt mixtures have always been a concern [9; 12]. Therefore, it is necessary to strengthen the monitoring of the production process of asphalt mixtures. The asphalt mixture production monitoring system consists of temperature monitoring, production quality monitoring, and energy environment monitoring systems. The system architecture is shown in Figure 4. The temperature monitoring module mainly monitors the aggregate conveying equipment and the mineral powder input equipment. The proportion of the aggregate and mineral powder is determined during the production process. The factors that can affect the quality of the asphalt mixture are mainly concentrated on the equipment. When the temperature  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Main Construction Process** & **Key Monitoring Indicators** \\ \hline Asphalt mixture production stage & Base bitumen, modifier, stabilizer, whetstone ratio, gradation, temperature, speed \\ Asphalt mixture mixing stage & Asphalt weight, mixture temperature, mixing time by plate, silo weight, discharge temperature, gradation \\ Asphalt mixture transportation stage & Loading time, loading location, transportation route, transportation time, transportation speed, vibration frequency, segregation \\ Asphalt paving stage & Paving trajectory, paving speed, distance Paving time, paving thickness, asphalt temperature \\ Asphalt mixture rolling stage & Rolling speed, rolling trajectory, rolling times, asphalt temperature, rolling strength, vibration frequency \\ \hline \hline \end{tabular}
\end{table}
Table 4: Monitoring indicators.  
Figure 3: Data linkage display.  
of the equipment is too high, the system will send an alarm, and the necessary staff can take the required measures to reduce the temperature of the equipment. The production quality monitoring module mainly monitors graduation, base asphalt, modifier, stabilizer, and oil-to-stone ratios. The system sets the ratio of various material indicators in advance, automatically monitors the quantity ratio of raw materials when the material enters the production equipment, and ensures the quality of asphalt by controlling the processing cycle. The energy and environmental monitoring module is responsible for monitoring energy consumption and carbon emissions in the production of aggregates, asphalt, mineral powder, and cement [28; 38].