Observing the Impact of Environmental Temperature and Traffic Loads on Cable-Stayed Bridges

Observing the Impact of Environmental Temperature and Traffic Loads on Cable-Stayed Bridges

Within their service life, bridges regularly bear external loads such as the weight of vehicles, temperature changes, wind, earthquakes, and the impact from river water. Although vehicle weight, temperature changes, and wind loads are exerted daily, they generally pose no immediate danger. Therefore, research on the daily behavior of bridges is significantly less common than research on the impact of earthquakes on bridges. Despite this difference in popularity, researching the daily load and behavior of bridges has a broad range of significance. First, the “standard” settings or “limits of safety” of a bridge can only be determined by measuring and statistically analyzing a bridge’s daily load and behavior. Second, detection instrument can automatically detect bridge changes anytime, allowing bridge managers to recognize the safety condition when an earthquake or flood may occur. Detection instruments can provide bridge safety surveillance, thereby protecting road users. Constant detection is the cornerstone of bridge safety surveillance. Based on this concept of bridge detection and safety, this study created a fiber optical elevation meter, which measures the change in a bridge’s girder elevation when under the dual load of temperature changes and vehicle weight. Then, we used the recorded data and analysis to simultaneously verify the theory and observation capabilities.