Measurement method, measurement device, measurement system, and measurement program

A measurement device, comprising:

• a memory configured to store a program;
• and
• a processor configured to execute the program so as to:
• generate, based on observation data output from a sensor configured to observe an observation point of a superstructure, first measurement data based on a physical quantity which is a response to actions of a plurality of parts of a vehicle moving on the superstructure on the observation point;
• generate second measurement data in which a vibration component is reduced by performing filter processing on the first measurement data;
• generate observation information including an entry time point and an exit time point of the vehicle with respect to the superstructure;
• calculate an average velocity of the vehicle based on the observation information and environment information which is created in advance and includes a dimension of the vehicle and a dimension of the superstructure;
• calculate, based on an approximate equation of deflection of the superstructure, the observation information, the environment information, and the average velocity, a first deflection amount of the superstructure caused by the vehicle;
• calculate a second deflection amount in which a vibration component is reduced by performing filter processing on the first deflection amount;
• approximate the second measurement data with a linear function of the second deflection amount to calculate a first-order coefficient and a zero-order coefficient of the linear function;
• calculate a third deflection amount based on the first-order coefficient, the zero-order coefficient, and the second deflection amount;
• calculate an offset based on the zero-order coefficient, the second deflection amount, and the third deflection amount;
• calculate a static response by adding the offset and a product of the first-order coefficient and the first deflection amount;
• calculate a first dynamic response by subtracting the static response from the first measurement data;
• calculate a second dynamic response by performing filter processing for attenuating an unnecessary signal from the first dynamic response;
• calculate an envelope amplitude of the second dynamic response;
• and
• calculate, based on the envelope amplitude, an attenuation rate of a vibration component included in the second dynamic response,
• wherein an abnormality state of the superstructure of the bridge is detected or monitored based on the attenuation rate of the vibration component.

A non-transitory computer-readable storage medium storing a measurement program, the measurement program causing a computer to execute a process by a processor so as to perform the steps of:

• generating, based on observation data output from a sensor configured to observe an observation point of a superstructure of a bridge, first measurement data based on a physical quantity which is a response to actions of a plurality of parts of a vehicle moving on the superstructure on the observation point;
• generating second measurement data in which a vibration component is reduced by performing filter processing on the first measurement data;
• generating observation information including an entry time point and an exit time point of the vehicle with respect to the superstructure;
• calculating an average velocity of the vehicle based on the observation information and environment information which is created in advance and includes a dimension of the vehicle and a dimension of the superstructure;
• calculating, based on an approximate equation of deflection of the superstructure, the observation information, the environment information, and the average velocity, a first deflection amount of the superstructure caused by the vehicle;
• calculating a second deflection amount in which a vibration component is reduced by performing filter processing on the first deflection amount;
• approximating the second measurement data with a linear function of the second deflection amount to calculate a first-order coefficient and a zero-order coefficient of the linear function;
• calculating a third deflection amount based on the first-order coefficient, the zero-order coefficient, and the second deflection amount;
• calculating an offset based on the zero-order coefficient, the second deflection amount, and the third deflection amount;
• calculating a static response by adding the offset and a product of the first-order coefficient and the first deflection amount;
• calculating a first dynamic response by subtracting the static response from the first measurement data;
• calculating a second dynamic response by performing filter processing for attenuating an unnecessary signal from the first dynamic response;
• calculating an envelope amplitude of the second dynamic response;
• and
• calculating, based on the envelope amplitude, an attenuation rate of a vibration component included in the second dynamic response,
• wherein an abnormality state of the superstructure of the bridge is detected or monitored based on the attenuation rate of the vibration component.