Research On Quality Evaluation Method Of Compaction Process Based On Cloud Service

The total mileage of the Chinese expressway has reached 131,000 km and is the longest in the world.The expressway promotes the development of China's economy.However,pavement quality problems always happen in the short term after construction.One of the main reasons is that the road construction project lacks compactness process quality monitoring during construction.The evaluation method is core sampling method which is a destructive method and its result has poor representative.During the construction process,the process parameters and machine' working parameters can't be monitored and stored.Once there is a compaction quality problem,the maintenance cost will be very high.Parameters associated with the compaction process cannot be traced back to the source.Therefore,an on-line monitoring system of compaction quality has become the hot topic in the recent year.But the existing research on compaction quality online monitoring is still in its infancy,there is an urgent need to study the on-line monitoring and evaluation method of the vibrating road roller and operation parameters during compaction process.It is of great significance to improve the construction management level and construction quality.According to the compaction process of roadbed and asphalt pavement,parameters of asphalt pavement temperature,number of compaction,compactness value,working velocity are proposed to be evaluate the compaction quality.Local area network(LAN)is employed for data sharing for working machines,internet is used for remote data transmission.Based on WIFI and 3G communicaiton,the monitor system for compaction process is designed,it can acquire the construction process parameters and working parameters during compact process.Aiming to improve the dynamic positioning precision,an optimized method based on Kalman filter method,Turboedit method and elimination of propagation path error method is employed for optimizing the GPS RTK base station's result.By comparing the original data and optimized data,it indicates that the optimization algorithm improves the positioning accuracy,and it meets the positioning precission requirements of JT/ t1127-2017.On this basis,pixel point analysis and raster method are used to calculate the number of compaction process for the construction of Liu-Nan expressway.The results show that the monitor system can get the RCC trajectory,rolling number and rolling speed during constructin.The method can avoid leakage area and overpressure area during construction,it achieves the control purpose during compaction process.To online detection of compactness value during compaction process,a compactness measurement system is constructed by harmonic method and LabVIEW.With compactenss experiment,a linear model between CCV value and compactness value was established,the correlation coefficient is higher than the requirement of JT T 1127-2017.CCV value can be used to evaluate the compactness value and can be used to online detection compactess status during construction.Combined with RTK GPS,the CCV can provide standard for judging the underpressure area,overpressure area,can also evaluate uniform of compact quality.According to the construction process,a continuous temperature detect method was provide to solve the exist detecting problem.And a temperature detecting system for asphalt pavement was constructed with STM32,infrared temperature sensor,humidity sensor and anemometer.Considering environmental factors,PSO-BP method was used to establish the temperature compensation model,the error of the model is <1.60%,which improves the accuracy of the measurement resut,and meets the requirements for the asphalt pavement construction.To solve the problem of data process,data storage and data share during compaction process,combination of IaaS and PaaS cloud service is adopted to design the evaluation system for compact quality.All the working parameters and construction process parameters are stored in the cloud center,the cloud service platform can be used to track and reload the parameters of construct process.The functions of the compactness quality cloud system are verified by construction project.The system is convenient for users to check the construction quality index and manage the construction project.This thesis provides a platform for the digital construction and compactness quality control for road construction;and it also provides a quality assurance method for mechanized construction.