桥梁结构动态变形信息是桥梁安全状态评估的重要指标之一。传统仪器监测桥梁目标振动需要布线、逐点监测、接触式测量,而地基雷达干涉测量成像(Image By Interferometric System-Structures,IBIS-S)系统具有高采样率、高精度、非接触等...桥梁结构动态变形信息是桥梁安全状态评估的重要指标之一。传统仪器监测桥梁目标振动需要布线、逐点监测、接触式测量,而地基雷达干涉测量成像(Image By Interferometric System-Structures,IBIS-S)系统具有高采样率、高精度、非接触等特点,在斜拉桥健康监测及维护管理中具有优势。以某双塔双索面钢箱梁与预应力混凝土组合斜拉桥为研究对象,采用IBIS-S系统对该桥进行动态监测,利用ESVMD-NExT方法对振动特性进行分析,并将结果与GPS全球定位系统的实测数据进行对比,充分验证了运用IBIS-S地基干涉雷达技术开展斜拉桥形变监测的可靠性。展开更多
Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traff...Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS （global positioning system） monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD （empirical mode decomposition） model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.展开更多
文摘桥梁结构动态变形信息是桥梁安全状态评估的重要指标之一。传统仪器监测桥梁目标振动需要布线、逐点监测、接触式测量,而地基雷达干涉测量成像(Image By Interferometric System-Structures,IBIS-S)系统具有高采样率、高精度、非接触等特点,在斜拉桥健康监测及维护管理中具有优势。以某双塔双索面钢箱梁与预应力混凝土组合斜拉桥为研究对象,采用IBIS-S系统对该桥进行动态监测,利用ESVMD-NExT方法对振动特性进行分析,并将结果与GPS全球定位系统的实测数据进行对比,充分验证了运用IBIS-S地基干涉雷达技术开展斜拉桥形变监测的可靠性。
文摘Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS （global positioning system） monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD （empirical mode decomposition） model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.
