Sensor-Based Damage Detection and Quantification in Bridges Under Traffic and Environmental Effects

该项目将开发一种可靠的方法来识别(检测和量化)暴露在环境温度和太阳辐射变化以及交通负荷下的桥梁的损害。该方法将利用从振动响应数据中提取的模态特性，并对热效应进行适当调整，以进行损伤识别。交通诱导振动数据和移动荷载的测量将被用于提取模态参数。为了验证所提出的模式估计方法，将利用在香港两座混凝土大桥上收集的现场数据。对于损伤识别，将发展基于改进的曲率柔度估计的损伤识别方法。为了评估热传导对模态参数的影响，将进行一项全面的研究，以提出仅利用年和日温度趋势以及数据记录时温度的现场测量来计算受温度影响的模态参数的简单方法。对于损伤量化，损伤结构的柔度特性将与未损伤的基线结构的柔度特性进行比较，以反映数据测量时温度环境的影响。

This project will develop a robust approach for damage identification (detection and quantification) of bridges exposed to environmental temperature and solar radiation variations and traffic loads. The approach will utilize the modal properties extracted from vibration response data with appropriate adjustments for thermal effects for damage identification. The traffic induced vibration data along with measurements on the moving loads will be used for the extraction of the modal parameters. For the validation of the proposed modal estimation approach, the field data collected on two concrete bridges in Hong Kong will be utilized. For damage identification, the methods based on the improved estimation of the curvature flexibility will be developed. A comprehensive study will be conducted to evaluate the effect of thermal conduction on the modal parameters to propose simple methods utilizing only the yearly and diurnal temperature trends and spot measurements of the temperature at the time of data recording to calculate the temperature affected modal parameters. For damage quantification, the flexibility characteristics of damaged structure will be compared with those of the undamaged baseline structure adjusted to reflect the effect of the temperature environment at the time of the data measurements.