It has been shown that the variations of structural properties due to changing environmental conditions such as temperature can be as significant as those caused by structural damage and even liveload. Therefore, tracking changes that are correlated with environmental variations is a necessary step in order to detect and assess structural damage in addition to the normal structural response to traffic. In this paper, daily measurement data that is collected from the concrete towers of the Ironton-Russell Bridge will be presented and correlation of the collected measurement data and temperature will be overviewed. Variation of the daily thermal response of tower concrete walls will be compared with the daily thermal responses of the steel box within the tower and finally, thermal coefficient for compensating the thermal induced responses will be estimated.
Proc. SPIE. 9805, Health Monitoring of Structural and Biological Systems 2016
KEYWORDS: Data modeling, Bridges, Structural health monitoring, Nondestructive evaluation, Performance modeling, Time series analysis, Data processing, Detection and tracking algorithms, Sensors, Data acquisition, Temperature metrology, Safety, Astatine, Databases, Multiplexers
Monitoring a complex structure has gained popularity worldwide to ensure safety and longevity of the structure. Structural Health Monitoring (SHM) systems have been employed for highway bridges to increase the effectiveness of their in-service inspection, to help measure its degradation or damage, and hence, to ensure it’s safe and reliable operation. SHM may also be employed during the construction of a structure in order to ensure the safety and performance of the construction process. Monitoring during construction can also help designers compare the actual behavior of a structure with design models especially because of increasing development of accelerated or otherwise novel construction techniques. Analyzing the behavior of a structure at different stages of construction may also help later define some of the abnormal responses during the lifespan of a bridge. This paper overviews the SHM system of the Ironton-Russell Bridge, Ohio at the construction stage of its substructure. The stages involved in monitoring such as instrumentation of sensors, acquiring data from the sensors, data processing that includes a warning system, static analysis of the data collected and website are detailed in this paper. In addition to this, the effect of construction events as observed by the sensor data for the substructure is analyzed in detail thus validating the capability of the monitoring system.