Structural health monitoring relating to a real-time tracking method for structural modal parameters. The Natural Excitation Technique transforms structural random responses into free decaying responses used to calculate structural modal parameters by the Eigensystem Realization Algorithm combined with the stabilization diagram. Considering influence of environmental excitation level on the number of identified modes, the reference mode list is formed by union of modes obtained from response sets in a day. Then the modes can be tracked automatically according to rules of minimum frequency difference and maximum Modal Assurance Criterion (MAC). To avoid mode mismatch problem caused by absence of threshold, frequency differences and MACs between all modes from the latter response set and all reference modes are calculated and the mode will be tracked into the cluster corresponding to the specified reference mode only in the case that their frequency difference is smallest and the MAC is largest.

A computer-implemented method is provided for estimating the remaining life of a structure being monitored by a sensor. The method includes: receiving data from a sensor, where the data is indicative of strain experienced by a structure and is reported as a plurality of cumulative distribution functions; extracting a probability density function from the data received from the sensor; computing a damage index for the structure from parameters of the probability density function, where the damage index is indicative of damage to the structure accumulated over time; and estimating a remaining life of the structure using the damage index.

The present application discloses a bridge structure comprising first supporting structure, at least one first hollow tube and a first monitor. The first supporting structure comprises bases, first pillars, a first platform. The first pillars are coupled to the bases, wherein each of the first pillars comprises first pillar chords and first pillar girders formed as first pillar trusses with the first pillar chords. The first platform coupled to the first pillars, wherein the first platform comprises a first supporting plane, first platform chords and first platform girders formed as first platform trusses with the first platform chords. The at least one first hollow tube is located between the first pillar trusses or the first platform trusses. The first monitor is located in the at least one first hollow tube, wherein the first monitor is capable of monitoring a bridge stability

Structural health monitoring relating to an automatic method for tracking structural modal parameters. First, Natural Excitation Technique is used to transform the random responses into correlation functions and Eigensystem Realization Algorithm combined with the stabilization diagram is used to estimate modal parameters from various response segments. Then, modes from the latter response segment are classified as traceable modes or untraceable modes according to correlations between their observability vectors and subspaces of the existing reference modes. Final, traceable modes will be grouped into specified clusters with the same structural characteristics on the basis of maximum modal observability vector correlation and minimum frequency difference. Meanwhile, union of the untraceable modes and existing reference modes are updated as the new reference modes which can be applied into the next tracking process. This can track the modal parameters automatically without artificial thresholds and the specified reference modes.

The invention relates to a method for determining the structural integrity of an infrastructural element, comprising the steps of: measuring deformations, such as displacements or rotations, during a predetermined time period with deformation measurement means arranged at or near a main structural body of the infrastructural element, in particular supports of the main structural body, characterized by determining the load configuration of the main structural body over the course of the predetermined time period, such as the load configuration concerning the loading perpendicular to a longitudinal direction of the main structural body, calculating the bending stiffness (EI) of the main structural body over the course of the predetermined time period, from the load configuration and deformations measured by the deformation measurement means, and comparing the bending stiffness (EI) at the end of the predetermined time period to the bending stiffness (EI) at the start of the predetermined time period to establish a difference in bending stiffness (EI) over the course of the predetermined time period.

Each of a plurality electronic circuit devices fixed to a structural component of a physical structure can be scanned a first time, using a radio frequency (RF) scanner to receive, from each of the plurality of electronic circuit devices, first data indicating a first measured electrical impedance of a respective conductor connected to the electronic circuit device and an identifier assigned to the electronic circuit device. For each of the plurality of electronic circuit devices, the first data indicating the first measured electrical impedance and the identifier assigned to the electronic circuit device can be stored to a first memory. The first data indicating the first measured electrical impedance and the identifier for each of the electronic devices can form a baseline measurement of the electronic circuit devices.

Health monitoring for civil structures, and a performance alarming method for long-span bridge girder considering time-varying effects. First, establish accurate relationship model between temperature and strain fields to eliminate the temperature effect in the girder strain; second, build principal component analysis model for the girder strain after eliminating temperature effect to further eliminate the effects of wind and vehicle loads. Then, construct the performance alarming index and determine its reasonable threshold for the strain after eliminating the effects of temperature, wind and vehicle loads. Finally, construct the performance degradation locating index based on the contribution analysis.

According to one embodiment, a structure evaluation system according to an embodiment includes a plurality of sensors, a position locator, and an evaluator. The plurality of sensors detect elastic waves. The position locator locates positions of elastic wave sources by using the elastic waves among the plurality of elastic waves respectively detected by the plurality of sensors having an amplitude exceeding a threshold value determined according to positions of the sources of the plurality of elastic waves and the positions of the plurality of disposed sensors. The evaluator evaluates a deteriorated state of the structure on the basis of results of the position locating of the elastic wave sources which is performed by the position locator.

A measurement method includes: a high-pass filter processing step of performing high-pass filter processing on target data including a drift noise to generate drift noise reduction data in which the drift noise is reduced, a correction data estimation step of estimating, based on the drift noise reduction data, correction data corresponding to a difference between the drift noise reduction data and data obtained by removing the drift noise from the target data, and a measurement data generation step of generating measurement data by adding the drift noise reduction data and the correction data.

A method is disclosed for measuring stress distribution generated on a structural object including two support parts and a beam part provided between the support parts. The method includes: generating first data by sensing, through a first sensing unit, of a moving object or an identification display object attached to the structural object; calculating, based on the first data, a movement duration in which the moving object moves between the support parts; generating, as second data, thermal data by sensing of a surface of the beam part through a second sensing unit; calculating a temperature change amount based on a second data group corresponding to the movement duration; and calculating a stress change amount based on the temperature change amount to calculate stress distribution based on the stress change amount.