Bridge Health Monitoring System Research And Design Based On Wireless Sensor Network

With the rapid development of transportation and economy in China,the number of bridges is increasing day by day,and the health monitoring of bridges is also extremely urgent.Therefore,real-time monitoring,condition assessment,early warning and damage identification of bridge structures are the current research trends.As a result,on the basis of bridge wired monitoring technology,this paper proposes a bridge health monitoring system based on wireless sensor network,which changes the drawbacks of cable sensor system vulnerable to aging and damage,and introduces cloud computing technology,reduces the cost of resources,improves the monitoring efficiency,and can view the monitoring structure and environmental data in real time,so that bridge monitors can make decisions quickly.The main contents of this paper are as follows:(1)This paper mainly introduces the principle of vibrating wire sensor and designs the signal acquisition card of vibrating wire sensor.The core module includes STM32 processor,channel selection circuit,excitation,vibration pickup circuit,Zig Bee CC2530 node and 4G module.Frequency and temperature signals are mainly collected,and eight channels are used to collect the results and accuracy to meet the needs ofbridge monitoring.(2)Designing server function.The server analyses and studies the monitoring data of frequency,temperature and other data through formula algorithm,and obtains the values of strain,load,displacement and vibration acceleration,and stores them in the database of SQL Server2014.The threshold level is determined and alarm information is issued.The alarm information contains three levels of alarm,which are divided according to different thresholds.(3)In this paper,two software architectures are designed to monitor bridge data more diversely.Mobile terminal and server adopt C / S(Client/Server)architecture.The functions of Android APP include real-time information monitoring,early warning information querying,patrol status uploading and information downloading.The second architecture is B/S(Browser/Server)architecture,which designs WEB pages.MVC(Model View Controller)frame is used to coordinate the agent modules.The system contains real-time data and historical data and alarm information querying,and managers can make decisions based on early warning information.The system aims at monitoring the health information of bridges,ensuring the safety of bridges,facilitating bridge inspection and management personnel,and has great market application value and research significance.(4)This paper studies the data correlation,the correlation betweenstrain,deflection and temperature is studied.The linear relationship between strain and temperature is obtained by using the correlation.The influence of temperature on the change is eliminated,and the strain caused by dynamic load is obtained,which provides a better basis for real-time early warning.