Study On Intelligent Compaction Quality Control Method And Engineering Application Of Earth-Rock Mixed Fill Subgrade

The evaluation of the compaction quality of soil-rock mixture subgrade is a concern for many construction participants,directly affecting the stability and durability of the subgrade and upper structure layer,as well as the driving experience for drivers.Currently,the compaction quality of soil-rock mixture subgrade is checked by sampling the entire section of the subgrade at certain frequencies using the settlement difference method.However,this "point" measurement method has many issues and cannot fully reflect the overall compaction quality of the entire subgrade,nor can it achieve comprehensive control of the compaction quality of the soil-rock mixture subgrade during the entire rolling operation.Therefore,it is important to develop a complete,real-time,processoriented,and universally applicable digital and intelligent compaction system for soilrock mixture subgrade.This paper first analyzes the quality control technology of soil-rock mixture subgrade at home and abroad,and then conducts in-depth research on the physical and mechanical properties of soil-rock mixture materials.Based on the on-site construction conditions,the paper obtains the maximum dry density,optimum moisture content,and porosity at different stone contents and water contents through indoor lightweight impact tests and surface vibration impact tests.The paper also provides construction limit stone content rates for different stone contents.Furthermore,based on the analysis of the research progress of intelligent compaction technology and the key points of soil-rock mixture subgrade construction technology control,this paper develops a complete program software including positioning,vibration acceleration,moisture content signal data acquisition,pre-processing,analysis processing,data merging,and compaction rolling result visualization.The software uses vibration acceleration sensors,location signal receivers,near-infrared moisture meters,and other supporting equipment,and is written in Python language.The paper also incorporates machine learning functions into the system,allowing the system to have autonomous learning capabilities through a storage + learning mode,which can be combined with a large amount of field detection data in the later stage to increase the application range and detection accuracy of intelligent compaction technology.Finally,based on the analysis of the main factors affecting the compaction quality of soil-rock mixture subgrade,this paper uses the controlled variable method in the experimental section to determine the coefficient of each influencing factor and optimize the calculation formula for intelligent compaction measurement values.The intelligent compaction target value of the soil-rock mixture subgrade intelligent compaction system is determined.Combined with construction practice,the paper compares the traditional method of subgrade compaction with the intelligent compaction technology and summarizes the advantages of the soil-rock mixture subgrade intelligent compaction system.The research results of this paper are applied to the compaction quality detection of soil-rock mixture subgrade rolling operation in the Linlin Expressway Section 4.It can solve the problem of difficult comprehensive judgment of compaction quality caused by the traditional "point" detection method.The system has good performance and can better meet the requirements of construction technical standards,guide soil-rock mixture subgrade construction,and reduce the probability of errors in soil-rock mixture subgrade compaction quality detection caused by manual and other factors,thereby reducing construction and management costs.The paper provides a new solution for characterizing the construction quality of soil-rock mixture subgrade and has important practical significance for improving the compaction process of soil-rock mixture subgrade.