| With the rise of tunnel engineering,shield machines have been widely used in urban tunnel construction.The structure of the shield machine is complex and the construction process is interlocking.Any problem in any link may bring huge losses to the project and the entire society.the Shanghai Municipal Science and Technology Commission’s local colleges and universities capacity building project,the Shanghai Metro Line 18 earth pressure balance shield machine is used as the research Objects,combined with shield construction safety risk assessment,use LabVIEW virtual instrument to carry out research on the monitoring and diagnosis of shield safety operation status.The main contents are as follows:(1)Based on the shield construction risks,combined with the accident cause theory,from the four risk factors of personnel factors,equipment factors,environmental factors,and management factors,carry out analysis of the causes of earth pressure balance shield construction and establish a fault tree;Based on the fault tree,conduct qualitative and quantitative analysis of shield system construction risks,and provide suggestions on shield construction safety management based on the analysis results.(2)According to the common failures of shield construction and the characteristics of the failures,relevant theoretical basis for dynamic signal processing,calculation,analysis,etc.is proposed for vibration signals.Including statistical analysis and correlation analysis in time domain analysis,and various spectrum analysis in frequency domain analysis.(3)Based on shield safety risk assessment,combined with shield construction principles,design an overall plan for monitoring and diagnosis.The monitoring content includes eight shield sub-systems such as cutter head system,propulsion system,and soil dumping system;the diagnosis object includes the diagnosis and analysis of the screw conveyor motor and gearbox with the soil dumping system as the center.(4)The software and hardware design scheme of the monitoring and diagnosis system of shield machine safety operation status is proposed.Including the selection of LabVIEW virtual instruments,and the selection and design of hardware configurations such as signal generators,sensors,data acquisition instruments,and workstations.(5)Based on on-site experimental data and some reference materials,combined with the application of shield system software and hardware,a complete shield safety operation status monitoring and diagnosis system is built.The content of the system is complete,with three modules: login system,monitoring system,and diagnostic system,with signal recognition,signal acquisition,data reading,alarm display,data storage,report printing,time domain analysis,frequency domain analysis,and analog monitoring and diagnostic control And many other functions.Based on the above-mentioned accident causation theory,carry out the analysis of the four risk factors in the accident causation model to construct a shield construction safety risk assessment;at the same time,to prevent the occurrence of shield safety accidents,combine realtime data of shield construction to build shield safety The operation status monitoring and diagnosis system provides a complete shield safety construction system for enterprises,and also provides reference for other engineering practices. |
