Bridge Dynamic Structural Health Monitoring桥梁动态健康监测案例
A long-term monitoring case built around traffic, wind, impact and local stress response. Distributed vibration and strain points are synchronized with geometry, temperature and operating conditions, so modal change and fatigue demand can be interpreted in engineering context.本案例围绕交通、风、冲击与局部应力响应开展长期监测。分布式振动和应变测点与桥梁几何、温度及运营工况统一同步，用于识别模态变化、疲劳需求及异常事件。
Separate Normal Operational Response from Structural Change区分正常运营响应与结构状态变化
The case retains raw synchronized waveforms and the environmental conditions behind each event. A change is judged against comparable temperature, wind and traffic states rather than against one fixed threshold.系统保留同步原始波形，同时记录事件发生时的温度、风与交通条件。状态判断基于同类工况对比，不使用脱离环境背景的单一固定阈值。
Deck and Tower Motion主梁与桥塔整体响应
Record vertical, lateral and torsional response under normal traffic, wind and exceptional events.记录日常交通、风荷载及异常事件下的竖向、横向与扭转响应。
Frequency, Mode and Damping频率、振型与阻尼
Track operational modal parameters by season and load state to expose persistent departures from baseline.按季节和荷载状态跟踪运营模态参数，识别持续偏离基线的变化。
Dynamic Strain and Stress Range动态应变与应力幅
Measure stress cycles at welds, diaphragms, anchor zones and section transitions under representative vehicles.测量焊缝、横隔板、锚固区与截面变化处在典型车辆作用下的应力循环。
Impact and Abnormal Excitation冲击与异常激励
Preserve pre-event and post-event waveforms for impact, sudden braking, bearing shock and strong-wind response.保留撞击、急刹、支座冲击及强风响应前后的完整波形。
Place Sensors by Load Path and Expected Mode Shape按照受力路径与预期振型布点
The delivered layout starts from structural drawings, finite-element modes, inspection findings and accessible cable routes. Symmetric points and common physical sections are retained wherever response comparison is required.布点以结构图纸、有限元振型、检查结果与可实施的走线路径为基础。需要响应对比的位置保留对称测点和同一物理截面，减少位置差异造成的误判。
| Zone分区 | Point placement测点位置 | Sensor type传感器类型 | Engineering purpose工程目的 |
|---|---|---|---|
| 01 · Main deck主梁 | Midspan, quarter spans, tower-adjacent sections and both deck edges跨中、四分点、近塔截面及桥面上下游两侧 | Vertical / lateral IEPE; triaxial IEPE or MEMS竖向/横向 IEPE，三轴 IEPE 或 MEMS | Vertical, lateral and torsional modes; traffic and wind response竖弯、侧弯与扭转振型，交通和风致响应 |
| 02 · Tower and pier桥塔与桥墩 | Tower top, tower-beam junction, pier top and representative foundations塔顶、塔梁结合部、墩顶及代表性基础位置 | Triaxial accelerometer, tilt and temperature三轴加速度、倾角与温度 | Tower modes, support stiffness and deck-pier coupling桥塔振型、支承刚度及梁墩耦合响应 |
| 03 · Cable and bearing索与支座 | Representative cable anchorage or cable body; bearing seats and expansion joints代表性索锚固区或索体，支座座板与伸缩缝附近 | Compact accelerometer, displacement and local strain小型加速度、位移与局部应变 | Cable-frequency trend, bearing shock, looseness and restraint change索频趋势、支座冲击、松动及约束状态变化 |
| 04 · Fatigue details疲劳细节 | Weld toes, diaphragms, anchor plates, openings and section transitions焊趾、横隔板、锚板、开孔与截面变化位置 | Foil strain gauge, rosette or weldable strain sensor箔式应变片、应变花或焊接式应变传感器 | Stress range, cycle counting and local fatigue demand应力幅、循环计数与局部疲劳需求 |
| 05 · Context工况背景 | Deck weather point, structural temperature, GNSS and traffic-event interface桥面气象点、结构温度、GNSS 与交通事件接口 | Weather, temperature, GNSS and event input气象、温度、GNSS 与事件输入 | Environmental normalization and event attribution环境归一化与事件归因 |
Final point count and orientation follow the bridge type, target modes, expected stress hot spots and accessible installation surfaces. The diagram shows the placement logic rather than a fixed bill of quantities.最终测点数量和方向根据桥型、目标振型、预期应力热点与可安装表面确定。图中表达布点逻辑，不作为固定设备数量表。
Use Different Sensors for Global Motion and Local Demand整体运动与局部受力采用不同传感器
Sensor range, noise floor, frequency response, installation mass and field durability are selected together. One sensor type is not forced across every point.量程、噪声、频响、附加质量与现场耐久性统一选型，不用一种传感器覆盖所有测点。
Precision Dynamic Points高保真动态测点
IEPE acceleration is used where phase, modal response, impact waveform and wide dynamic range are required.需要相位、模态响应、冲击波形与宽动态范围的位置采用 IEPE 加速度传感器。
MEMS · LONG TERMDistributed Long-Term Points分布式长期测点
Low-power MEMS points provide dense operating response and event screening where permanent deployment matters most.低功耗 MEMS 用于需要长期布设的分布式响应监测与事件筛查。
STRAIN · 1/4 / 1/2 / FULLStress Hot Spots应力热点
Foil gauges and rosettes record local stress cycles at details that global acceleration cannot resolve.应变片与应变花记录整体加速度无法分辨的局部应力循环。
GNSS · WEATHER · TEMPStructural Context结构与环境背景
Geometry, wind and temperature explain slow drift and separate operational variation from structural anomalies.几何、风与温度用于解释慢变趋势，并区分运营波动与结构异常。
Continuous Overview plus Triggered Raw Waveforms连续概览数据结合事件原始波形
Acquisition nodes are installed near sensor groups to control cable length. All dynamic channels in one analysis group share a common sample clock, calibration table and channel-orientation definition.采集节点就近布置在传感器分组附近，控制模拟电缆长度。同一分析组内的动态通道使用统一采样时钟、标定表与通道方向定义。
Point Configuration测点配置
- Sensitivity and orientation灵敏度与方向
- Cable and mounting record电缆与安装记录
Synchronized DAQ同步数采
- IEPE constant currentIEPE 恒流供电
- Bridge excitation and completion桥路激励与补桥
Two Record Modes两类记录模式
- Scheduled continuous windows定时连续数据窗
- Pre/post-event waveform事件前后波形
Edge and Cloud边缘与云端
- Local raw-data buffer本地原始数据缓存
- Features plus selected files特征量与选定文件上传
Data Quality数据质量
- Clock, range and clipping时钟、量程与削顶
- Noise and missing-data flags噪声与缺测标记
Eight-Channel IEPE Acquisition八通道 IEPE 专用采集
Used for phase-consistent acceleration groups. The unit provides eight synchronized 24-bit channels, up to 102.4 kS/s per channel, local recording and engineering-unit conversion.用于相位一致的加速度测点组。设备提供八路 24 bit 同步采集、每通道最高 102.4 kS/s、本地记录与工程量换算。
View IEPE DAQ查看 IEPE 数采 →PRO-AQ Max Multi-Physics AcquisitionPRO-AQ Max 多物理量采集
Used where IEPE acceleration and quarter-, half- or full-bridge strain must enter one synchronized record. Each channel supports up to 204.8 kS/s with dual 24-bit conversion.用于 IEPE 加速度与四分之一桥、半桥或全桥应变进入同一同步记录。每通道最高 204.8 kS/s，采用双 24 bit 转换。
View PRO-AQ Max查看 PRO-AQ Max →Process Every Event from Signal Quality to Maintenance Action从信号质量检查到养护动作形成闭环
The analysis retains traceability to the original waveform. Automated features support screening; engineering review confirms whether a persistent change warrants inspection.所有分析结果都可追溯到原始波形。自动特征量用于快速筛查，持续变化再由工程人员复核并决定是否启动检查。
Clean and Qualify预处理与质量标记
Apply calibration, orientation correction, de-trending, anti-alias filtering, clock checks, clipping detection and missing-data flags.完成标定、方向修正、去趋势、抗混叠滤波、时钟检查、削顶识别与缺测标记。
Event Response事件时域响应
Calculate peak, RMS, crest factor, duration, impulse and channel-to-channel arrival sequence for traffic and impact events.计算交通与冲击事件的峰值、RMS、峰值因子、持续时间、冲量及跨通道到达顺序。
Frequency Content频域特征
Track dominant frequency, broadband energy, harmonics, cross-power and coherence under comparable operating states.在可比工况下跟踪主频、宽带能量、谐波、互功率谱与相干性。
Operational Modal Tracking运营模态跟踪
Use multi-channel response to identify natural frequency, damping and mode-shape trends without interrupting traffic.利用多通道运营响应识别自振频率、阻尼与振型趋势，无需中断交通。
Stress Cycles应力循环
Convert compensated strain to stress range, perform rainflow counting and maintain fatigue-demand histories by detail category.将温度补偿后的应变换算为应力幅，进行雨流计数，并按构造细节保存疲劳需求历程。
Environmental Normalization环境归一化
Group baselines by temperature, wind and traffic level, then evaluate residual change with multi-sensor confirmation.按温度、风与交通等级建立分组基线，再结合多类传感器确认残差变化。
Alarm logic:报警逻辑： data-quality alarm first, event threshold second, persistent baseline deviation third. High-level structural alarms require agreement between related points or between vibration, strain and geometry evidence before an inspection task is issued.先判断数据质量，再判断事件阈值，最后判断基线持续偏离。高等级结构报警需要相关测点之间，或振动、应变与几何证据之间相互印证，再生成现场检查任务。
Data, Baselines and Inspection Evidence Remain Together数据、基线与检查证据统一管理
The monitoring result is delivered as a traceable engineering record rather than a collection of isolated dashboards.监测成果以可追溯的工程记录交付，不把结果停留在彼此割裂的看板上。
Live Condition View在线状态总览
Point health, operating state, event list, waveform preview, trends and alarm acknowledgment.集中显示测点健康、运营工况、事件列表、波形预览、趋势与报警闭环。
Modal and Fatigue Reports模态与疲劳报告
Periodic modal trends, representative events, stress spectra and environmental normalization results.定期输出模态趋势、代表事件、应力谱与环境归一化结果。
Inspection Work Orders检查与养护工单
Link anomalies to the affected component, supporting waveform, inspection photo and final disposition.把异常与对应构件、支撑波形、现场照片及最终处置结果关联保存。
Related delivered bridge-monitoring experience includes Baijusi Yangtze River Bridge, Suzhou Wusong River Bridge and Tangjiawan Bridge monitoring-system engineering.相关桥梁监测交付经验包括白居寺长江大桥、苏州中环吴淞江大桥及唐家湾特大桥健康监测系统工程。
Define the bridge, target modes and stress details first先明确桥型、目标振型与应力细节
Provide the bridge type, span arrangement, drawings, target events, available power and communication, required reporting interval and existing monitoring interfaces. Rasber will complete the point layout, sensor configuration and acquisition design.提供桥型、跨径布置、结构图纸、目标事件、供电通信条件、报告周期及现有监测接口，瑞茨柏将完成测点布置、传感器配置与采集设计。