基于有限测点的悬索桥位移场获取与安全评估

为对桥梁进行位移监测与安全评估,提出了基于有限点监测的桥梁位移获取技术和桥梁安全评估技术。首先通过实际的监测方案对有限点进行监测,反算荷载加载到有限元模型,实现全桥的实时有限元分析。接着将位移实测值经过处理后作为"实测值",分析得到各个截面位移所对应的"包络区间",最后将位移指标的包络区间是否能包络其对应的实测值作为评估的判断条件。综合分析表明:将六个监测点信息都用于反算,得到的监测点值与实测值基本符合,两者差值在5%以内,后续可采用临时监测信息来检验反算荷载的准确性;该大桥最大容许挠度为L/300=380×1 000/300=1 266.7 mm。从提取的历史数据中最大挠度为:1 029.3 mm,在容许挠度范围内,由此可见大桥运营状况良好。采用基于有限点监测的桥梁位移获取技术和桥梁安全评估技术,可以实现对桥梁进行位移监测和安全评估的要求。

Displacement Field Acquisition and Safety Assessment of Suspension Bridges Based on Limited Measurement Points

In order to monitor the displacement of the bridge, this paper presents a bridge displacement access technology and bridge safety assessment technology based on finite point monitoring. Firstly, the finite point is monitored by the actual monitoring scheme, and the finite element model is implemented to realize the real time finite element analysis of the whole bridge. Then, after processing as the "actual value" of the measured displacements, each section corresponding to the displacement of "envelope interval", the empirical envelope interval displacement index can envelope the corresponding values as the judgment condition assessment. Comprehensive analysis shows that the six monitoring points of information are used to inverse the measured value, the obtained deformation is in agreement with the subsequent interim monitoring information to test the accuracy of calculation load; the maximum allowable bridge immunity is L/300=380 × 1000/300=1266.7 mm. From the extraction of the historical data, the maximum degree of disturbance is: 1029.3 mm, in the range of allowable disturbance degree, this shows that the bridge is in good condition. The displacement monitoring and safety assessment of the bridge can be realized by using the technology of bridge displacement acquisition and bridge safety assessment based on finite point monitoring.