Monitoring and evaluating techniques of highway subgrade safety in the operation period

Operation safety of highway subgrade structure has become the most concerned issue which needs to be solved. Depending on the operational connotation requirements of the subgrade safety, a lot of investigations, and indoor and outdoor experimental and theoretical analyses are carried out. Based on the subgrade overall stability and pavement performance, the embankment safety monitoring technology and the early warning system are established, as well as the subgrade structure safety evaluation index and standard under typical working conditions. Highway subgrade cracking displacement acquisition device with a function of real-time monitor and wireless transmission is researched and developed independently, and acquisition subgrade cracking displacement method is proposed. Integrating the project research results, the subgrade structural safety monitoring and maintenance management system with subgrade monitoring data analysis and forecasting, safety hazards identification, safety assessment and early warning, conservation decision-making functions are developed. Project research achievements have been used in highway subgrade stability of longevity and continuity of safety monitoring. They provide a scientific basis for formulating appropriate maintenance decisions.