【摘要】 为了对混凝土桥梁应变变化以及裂缝出现进行全程监测,利用导电膜电阻拉-敏效应,提出了一种将导电膜布设在混凝土结构表面的新型结构健康监测技术。在实验室内制作混凝土试验梁,将导电膜与应变计共同布设在梁底面,进行该技术的验证试验,并与ANSYS有限元仿真模拟结果进行对比。试验结果确定了在试验梁出现裂缝前的弹性变形范围内,应变与导电膜电阻之间的定量关系;当结构表面出现裂缝时,导电膜电阻瞬时急剧增加,确定了其电阻增量与裂缝宽度的关系。将导电膜粘贴在混凝土表面观察其电阻的突变情况能够判断裂缝发生的时间,进而明确裂缝的位置,并随着裂缝的发展进行持续的测量。更多还原

【Abstract】 The pull-sensitizing of conductive film resistor was applied to monitor the process of strain changes and crack generations in bridge structure.The conductive film resistor was attached to the surface of the concrete structure for its health monitoring.The concrete beam was made in the laboratory,and the conductive film together with strain gauge was wired in the underside of the beam to carry out the crack monitoring tests.The test results were compared with that of ANSYS finite element simulation.The quantitative relationship between strain and the change of the resistance of the film was identified within the elastic deformation range before the appearance of the crack.When the crack occurred on the structure surface,the instantaneous resistance increased dramatically,and the relationship between the resistance of the film and the crack width was determined.The resistance mutations were observed to determine the occurrence time and location of the crack.Then,the development of the crack was continuously measured.更多还原