梁及桥梁应变模态与损伤测量的新方法

New approach for strain modal measurement and damage detection of bridges

由于梁式结构的应变状况与其刚度有直接关系 ,因此对应变模态的测量可望用于桥梁损伤识别。梁的曲率模态和应变模态是直接关联的。通过对实桥标准简支梁损伤的数值仿真 ,揭示了曲率模态对桥梁损伤的敏感性。为便于检测损伤 ,还提出了一个新的损伤识别指标—应力变化陡峭度D,并推荐一种具有高灵敏度和高一致性的

This paper studies a new approach of strain mode for damage detection of bridges. The strain status has direct relationship with the stiffness status of a girder structure. Damage could be detected from strain information of bridges. The curvature mode of girders is relating with the strain mode. Numerical simulation was carried out on a real bridge, demonstrating the sensitivity of strain mode for damage detect. A new index D, the abruptness of stress change, was proposed for more convenient detection of damage. A low frequency vibration transducer (type DP) is recommended for measuring the strain due to its high sensitivity and uniformity.