CN106441749A - Bridge dynamic deflection detection method and device based on microwave interference - Google Patents
Bridge dynamic deflection detection method and device based on microwave interference Download PDFInfo
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Abstract
本发明公开了一种基于微波干涉的桥梁动挠度检测的方法及装置，该方法包括：S1：获取微波干涉检测系统对待检测的桥梁检测过程中的几何特征参数，以及本次检测时的大气干温、大气水蒸气分压力和大气干空气分压力；S2：根据所述大气干温、大气水蒸气分压力和大气干空气分压力计算本次检测时的大气折射率；S3：根据所述大气折射率和所述几何特征参数，采用桥梁动挠度改正模型计算本次检测的所述桥梁的动挠度。该方法考虑了大气干温、大气水蒸气分压力和大气干空气分压力对微波传播过程的影响，避免了由于季节和时间的差异，温度、湿度、大气压力等环境因素对地面微波干涉检测精度的影响，提高了桥梁动挠度的检测精度。
The invention discloses a method and device for detecting bridge dynamic deflection based on microwave interference. temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure; S2: calculate the atmospheric refractive index during this test based on the atmospheric dry temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure; S3: The refractive index and the geometric characteristic parameters are used to calculate the dynamic deflection of the bridge detected this time by using the bridge dynamic deflection correction model. This method takes into account the influence of atmospheric dry temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure on the microwave propagation process, and avoids the influence of environmental factors such as temperature, humidity, and atmospheric pressure on the ground microwave interference detection accuracy due to seasonal and time differences. The influence of the bridge dynamic deflection is improved.
Description
技术领域technical field
本发明属于桥梁检测技术领域，具体涉及一种基于微波干涉的桥梁动挠度检测的方法及装置。The invention belongs to the technical field of bridge detection, and in particular relates to a method and device for detecting bridge dynamic deflection based on microwave interference.
背景技术Background technique
随着高速铁路的发展，我国高铁的运营里程已达两万公里。其中桥梁占线路比例平均约为54％。铁路桥梁运营期间，由于各种原因，会造成其不同程度的损伤和破坏。为了保证既有铁路桥梁的安全运营，并尽可能延长其使用年限，需要一种高频率，高精度的技术手段检测梁体过载时的动挠度量，进而对其健康状态和安全性进行分析和评估。With the development of high-speed railways, the operating mileage of my country's high-speed railways has reached 20,000 kilometers. Among them, bridges account for about 54% of the route on average. During the operation of railway bridges, various degrees of damage and destruction will be caused due to various reasons. In order to ensure the safe operation of existing railway bridges and prolong their service life as much as possible, a high-frequency, high-precision technical means is needed to detect the deflection of the beam body when it is overloaded, and then analyze its health status and safety. Evaluate.
目前用于铁路桥梁动态动挠度检测的技术分为接触式方法和非接触式方法。接触式方法可以获取较高的精度，如加速度计、激光干涉仪、位移计和LVDT等传感器，但是其需要固定在铁路桥梁的检测位置，尤其是位于道路、河流和沟渠等之上的铁路桥梁，无疑会增加铁路桥梁动态动挠度检测的难度。为了克服接触式传感器的缺点，非接触式方法已经成为桥梁动态动挠度检测的热点，主要包括激光、GPS、视觉检测和地基干涉雷达。At present, the technologies used to detect the dynamic deflection of railway bridges are divided into contact methods and non-contact methods. Contact methods can obtain higher accuracy, such as accelerometers, laser interferometers, displacement meters and LVDT sensors, but they need to be fixed at the detection position of railway bridges, especially railway bridges located on roads, rivers and ditches, etc. , will undoubtedly increase the difficulty of dynamic deflection detection of railway bridges. In order to overcome the shortcomings of contact sensors, non-contact methods have become a hotspot for bridge dynamic deflection detection, mainly including laser, GPS, visual detection and ground-based interferometric radar.
激光是一种高精度检测位移变化的技术，精度可达0.1mm，但是其设备昂贵，且不能获取垂直于激光束的位移变化。GPS用于大型柔性结构物(例如悬索桥)的动态位移检测比较适宜，但由于其误差与位移值几乎是同数量级，并不适用于位移变化较小的钢筋混凝土结构物的动态形变检测，且采样频率一般低于20Hz，另外随机噪声和多路径效应增加了数据分析的难度。视觉检测是另外一种有效的非接触检测手段，其主要采用高速相机、同步控制器、高速采集卡和人工目标点等构成，尽管其相对精度可以达到1:10000，但是海量数据处理和控制网布设的复杂性大大降低了效率。总之，传统动挠度检测技术的检测范围小、检测距离短、精度低、受环境影响大。Laser is a high-precision technology for detecting displacement changes, with an accuracy of up to 0.1 mm, but its equipment is expensive and cannot obtain displacement changes perpendicular to the laser beam. GPS is suitable for dynamic displacement detection of large flexible structures (such as suspension bridges), but because its error is almost the same order of magnitude as the displacement value, it is not suitable for dynamic deformation detection of reinforced concrete structures with small displacement changes, and sampling The frequency is generally lower than 20Hz, and random noise and multipath effects increase the difficulty of data analysis. Visual inspection is another effective non-contact inspection method, which is mainly composed of high-speed cameras, synchronous controllers, high-speed acquisition cards and artificial target points. Although its relative accuracy can reach 1:10000, massive data processing and control network The complexity of the layout greatly reduces the efficiency. In short, the traditional dynamic deflection detection technology has a small detection range, a short detection distance, low precision, and is greatly affected by the environment.
发明内容Contents of the invention
本发明所要解决的技术问题是如何提高桥梁动挠度的检测精度。The technical problem to be solved by the invention is how to improve the detection accuracy of bridge dynamic deflection.
针对这一技术问题，本发明提供了一种基于微波干涉的桥梁动挠度检测的方法，包括：To solve this technical problem, the present invention provides a method for detecting bridge dynamic deflection based on microwave interference, including:
S1：获取微波干涉检测系统对待检测的桥梁检测过程中的几何特征参数，以及本次检测时的大气干温、大气水蒸气分压力和大气干空气分压力；S1: Obtain the geometric characteristic parameters of the bridge to be detected by the microwave interference detection system, as well as the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure during this detection;
S2：根据所述大气干温、大气水蒸气分压力和大气干空气分压力计算本次检测时的大气折射率；S2: Calculate the atmospheric refractive index during this detection according to the atmospheric dry temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure;
S3：根据所述大气折射率和所述几何特征参数，采用桥梁动挠度改正模型计算本次检测的所述桥梁的动挠度；S3: Calculate the dynamic deflection of the bridge detected this time by using a bridge dynamic deflection correction model according to the atmospheric refractive index and the geometric characteristic parameters;
其中，所述几何特征参数包括所述微波干涉检测系统的雷达的中心点到所述桥梁下表面所在平面的距离、以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离。Wherein, the geometric characteristic parameters include the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained at least once to the The radial distance between the points to be detected on the bridge.
可选地，所述步骤S2包括：Optionally, the step S2 includes:
按照公式计算本次检测时的所述大气折射率；according to the formula Calculate the atmospheric refractive index during this detection;
其中，n表示所述大气折射率，t表示所述大气干温，pd表示所述大气干空气分压力，pw表示所述大气水蒸气分压力。Wherein, n represents the refractive index of the atmosphere, t represents the dry temperature of the atmosphere, p d represents the partial pressure of the dry air in the atmosphere, and p w represents the partial pressure of the water vapor in the atmosphere.
可选地，所述步骤S3包括：Optionally, the step S3 includes:
获取所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离，以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离；Obtain the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the center point of the radar of the microwave interference detection system obtained by at least one detection to the point to be detected on the bridge The radial distance between;
按照公式计算所述待检测点在垂直所述桥面下表面的方向上，偏离平行于所述桥面下表面的参考平面的距离，作为本次检测时的所述桥梁的动挠度；according to the formula Calculating the distance of the point to be detected from a reference plane parallel to the lower surface of the bridge deck in a direction perpendicular to the lower surface of the bridge deck, as the dynamic deflection of the bridge during this detection;
其中，di表示本次检测时的所述桥梁的动挠度，Ri表示第i次检测得到的径向距离，Ri-1表示第i-1次检测得到的径向距离，n表示所述大气折射率，h表示微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离。Among them, d i represents the dynamic deflection of the bridge during this detection, R i represents the radial distance obtained from the ith detection, R i-1 represents the radial distance obtained from the i-1 detection, and n represents the The atmospheric refractive index, h represents the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located.
可选地，所述桥梁下表面平行于所述桥梁上的路面所在的平面。Optionally, the lower surface of the bridge is parallel to the plane where the road surface on the bridge is located.
可选地，所述参考平面平行于所述桥梁下表面，且与所述桥梁下表面的之间的距离等于其与所述路面所在平面之间的距离；Optionally, the reference plane is parallel to the lower surface of the bridge, and the distance from the lower surface of the bridge is equal to the distance from the plane where the road surface is located;
所述待检测点位于所述参考平面内。The points to be detected are located in the reference plane.
另一方面，本发明还提供了一种基于微波干涉的桥梁动挠度检测的装置，包括：On the other hand, the present invention also provides a device for detecting bridge dynamic deflection based on microwave interference, including:
获取模块，用于获取干涉检测系统对待检测的桥梁检测过程中的几何特征参数，以及本次检测时的大气干温、大气水蒸气分压力和大气干空气分压力；The obtaining module is used to obtain the geometric characteristic parameters of the bridge to be detected by the interference detection system, as well as the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure during this detection;
计算模块，用于根据所述大气干温、大气水蒸气分压力和大气干空气分压力计算本次检测时的大气折射率；Calculation module, for calculating the atmospheric refractive index during this detection according to the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure;
处理模块，用于根据所述大气折射率和所述几何特征参数，采用桥梁动挠度改正模型计算本次检测的所述桥梁的动挠度；The processing module is used to calculate the dynamic deflection of the bridge detected this time by using a bridge dynamic deflection correction model according to the atmospheric refractive index and the geometric characteristic parameters;
其中，所述几何特征参数包括所述微波干涉检测系统的雷达的中心点到所述桥梁下表面所在平面的距离、以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离。Wherein, the geometric characteristic parameters include the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained at least once to the The radial distance between the points to be detected on the bridge.
可选地，所述计算模块用于按照公式计算本次检测时的所述大气折射率；Optionally, the calculation module is used according to the formula Calculate the atmospheric refractive index during this detection;
其中，n表示所述大气折射率，t表示所述大气干温，pd表示所述大气干空气分压力，pw表示所述大气水蒸气分压力。Wherein, n represents the refractive index of the atmosphere, t represents the dry temperature of the atmosphere, p d represents the partial pressure of the dry air in the atmosphere, and p w represents the partial pressure of the water vapor in the atmosphere.
可选地，所述处理模块包括：Optionally, the processing module includes:
获取单元，用于获取所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离，以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离；An acquisition unit, configured to acquire the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained by at least one detection to the bridge The radial distance between the points to be detected on ;
计算单元，用于按照公式计算所述待检测点在垂直所述桥面下表面的方向上，偏离平行于所述桥面下表面的参考平面的距离，作为本次检测时的所述桥梁的动挠度；Calculation unit, used to follow the formula Calculating the distance of the point to be detected from a reference plane parallel to the lower surface of the bridge deck in a direction perpendicular to the lower surface of the bridge deck, as the dynamic deflection of the bridge during this detection;
其中，di表示本次检测时的所述桥梁的动挠度，Ri表示第i次检测得到的径向距离，Ri-1表示第i-1次检测得到的径向距离，n表示所述大气折射率，h表示所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离。Among them, d i represents the dynamic deflection of the bridge during this detection, R i represents the radial distance obtained from the ith detection, R i-1 represents the radial distance obtained from the i-1 detection, and n represents the The atmospheric refractive index, h represents the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located.
可选地，所述桥梁下表面平行于所述桥梁上的路面所在的平面。Optionally, the lower surface of the bridge is parallel to the plane where the road surface on the bridge is located.
可选地，所述参考平面平行于所述桥梁下表面，且与所述桥梁下表面的之间的距离等于其与所述路面所在平面之间的距离；Optionally, the reference plane is parallel to the lower surface of the bridge, and the distance from the lower surface of the bridge is equal to the distance from the plane where the road surface is located;
所述待检测点位于所述参考平面内。The points to be detected are located in the reference plane.
本发明提供的了一种基于微波干涉的桥梁动挠度检测的方法及装置中，该方法考虑到微波在大气传播过程中会受到温度、湿度、大气压力等环境因素的影响，对大气干温、大气水蒸气分压力和大气干空气分压力分别进行检测，并由此确定大气折射率。根据由此确定的大气折射率，以及检测过程中微波干涉仪和桥梁之间的几何位置关系确定的几何特征参数，计算出桥梁的动挠度。这种方法避免了由于季节和时间的差异，温度、湿度、大气压力等环境因素对地面微波干涉检测精度的影响，提高了桥梁动挠度的检测精度。The present invention provides a method and device for detecting bridge dynamic deflection based on microwave interference. The method takes into account that microwaves will be affected by environmental factors such as temperature, humidity, and atmospheric pressure during the propagation of the atmosphere. Atmospheric water vapor partial pressure and atmospheric dry air partial pressure are detected separately, and the atmospheric refractive index is determined accordingly. The dynamic deflection of the bridge is calculated according to the determined atmospheric refractive index and the geometric characteristic parameters determined by the geometric positional relationship between the microwave interferometer and the bridge during the detection process. This method avoids the influence of environmental factors such as temperature, humidity, and atmospheric pressure on the accuracy of ground microwave interference detection due to differences in seasons and time, and improves the detection accuracy of bridge dynamic deflection.
附图说明Description of drawings
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作一简单地介绍，显而易见地，下面描述中的附图是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.
图1是本发明一个实施例提供的基于微波干涉的桥梁动挠度检测的方法的流程示意图；Fig. 1 is a schematic flow chart of a method for detecting bridge dynamic deflection based on microwave interference provided by an embodiment of the present invention;
图2是本发明一个实施例提供的桥梁的下表面、待检测点、参考平面所在位置的示意图；Fig. 2 is a schematic diagram of the lower surface of the bridge provided by one embodiment of the present invention, the points to be detected, and the position of the reference plane;
图3是本发明一个实施例提供的基于微波干涉的桥梁动挠度检测的装置的结构框图。Fig. 3 is a structural block diagram of a device for detecting bridge dynamic deflection based on microwave interference provided by an embodiment of the present invention.
具体实施方式detailed description
为使本发明实施例的目的、技术方案和优点更加清楚，下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.
图1是本实施例提供的基于微波干涉的桥梁动挠度检测的方法的流程示意图，参见图1，该方法包括：Fig. 1 is a schematic flow chart of a method for detecting bridge dynamic deflection based on microwave interference provided in this embodiment, referring to Fig. 1, the method includes:
S1：获取微波干涉检测系统对待检测的桥梁检测过程中的几何特征参数，以及本次检测时的大气干温、大气水蒸气分压力和大气干空气分压力；S1: Obtain the geometric characteristic parameters of the bridge to be detected by the microwave interference detection system, as well as the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure during this detection;
S2：根据所述大气干温、大气水蒸气分压力和大气干空气分压力计算本次检测时的大气折射率；S2: Calculate the atmospheric refractive index during this detection according to the atmospheric dry temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure;
S3：根据所述大气折射率和所述几何特征参数，采用桥梁动挠度改正模型计算本次检测的所述桥梁的动挠度；S3: Calculate the dynamic deflection of the bridge detected this time by using a bridge dynamic deflection correction model according to the atmospheric refractive index and the geometric characteristic parameters;
其中，所述几何特征参数包括所述微波干涉检测系统的雷达的中心点到所述桥梁下表面所在平面的距离、以及至少一次检测得到的微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离。Wherein, the geometric characteristic parameters include the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained by at least one detection to the bridge The radial distance between the points to be detected.
需要说明的是，微波干涉检测系统的雷达的中心点指的是雷达的天线上发射电磁波的发射点，或者是雷达上用于接收电磁波的接收盘的几何中心。It should be noted that the center point of the radar of the microwave interferometric detection system refers to the transmitting point on the antenna of the radar that emits electromagnetic waves, or the geometric center of the receiving dish on the radar for receiving electromagnetic waves.
待检测点位于桥梁上的路面所在平面和桥梁下表面所在平面之间。The point to be detected is located between the plane of the road surface on the bridge and the plane of the lower surface of the bridge.
动挠度指的是待检测点在垂直于路面所在平面的方向上偏移预先规定的一个参考平面或者参考点的偏移距离。对应一个待检测点，每次检测均能得到一个动挠度，因此，可以对待检测点进行多次检测，求出得到的所有动挠度的平均值作为该桥梁的动挠度，或者，也可以在桥梁上选取多个点作为待监测点，同时检测这些待监测点的动挠度，最后通过平均值的算法得到一个数值，作为该桥梁的动挠度。The dynamic deflection refers to the deviation distance of the point to be detected from a predetermined reference plane or reference point in the direction perpendicular to the plane where the road surface is located. Corresponding to a point to be detected, a dynamic deflection can be obtained for each detection. Therefore, multiple detections can be carried out on the point to be detected, and the average value of all the obtained dynamic deflections can be obtained as the dynamic deflection of the bridge, or it can be Select multiple points as the points to be monitored, and detect the dynamic deflection of these points to be monitored at the same time, and finally obtain a value through the average value algorithm as the dynamic deflection of the bridge.
在本实施例中，由于地面微波干涉检测的工作雷达发射的信号是一种位于Ku-波段的电磁波，其在大气传播过程中会受到温度、湿度、大气压力等环境因素的影响，引起电磁波信号的传播延迟和传播路径的弯曲，降低地面微波干涉检测的精度。而在长周期的铁路桥梁动挠度检测过程中，由于季节和时间的差异，温度、湿度、大气压力等环境因素对地面微波干涉检测精度的影响将进一步加大。通过本实施例的测量方法可以解决传统动挠度检测技术的检测范围小、检测距离短、精度低、受环境影响等诸多问题。In this embodiment, since the signal emitted by the working radar of ground microwave interference detection is an electromagnetic wave located in the Ku-band, it will be affected by environmental factors such as temperature, humidity, and atmospheric pressure during atmospheric propagation, causing electromagnetic wave signals The propagation delay and the bending of the propagation path reduce the accuracy of ground microwave interference detection. In the long-term dynamic deflection detection process of railway bridges, due to differences in seasons and time, environmental factors such as temperature, humidity, and atmospheric pressure will further increase the impact on the accuracy of ground microwave interference detection. Through the measurement method of this embodiment, many problems such as small detection range, short detection distance, low precision, and environmental influence of the traditional dynamic deflection detection technology can be solved.
本发明提供的了一种基于微波干涉的桥梁动挠度检测的方法，该方法考虑到微波在大气传播过程中会受到温度、湿度、大气压力等环境因素的影响，对大气干温、大气水蒸气分压力和大气干空气分压力分别进行检测，并由此确定大气折射率。根据由此确定的大气折射率，以及检测过程中微波干涉仪和桥梁之间的几何位置关系确定的几何特征参数，计算出桥梁的动挠度。这种方法避免了由于季节和时间的差异，温度、湿度、大气压力等环境因素对地面微波干涉检测精度的影响，提高了桥梁动挠度的检测精度。The invention provides a method for detecting bridge dynamic deflection based on microwave interference. The method takes into account that microwaves will be affected by environmental factors such as temperature, humidity, and atmospheric pressure during the propagation of the atmosphere. The partial pressure and atmospheric dry air partial pressure are detected separately, and the atmospheric refractive index is determined from this. The dynamic deflection of the bridge is calculated according to the determined atmospheric refractive index and the geometric characteristic parameters determined by the geometric positional relationship between the microwave interferometer and the bridge during the detection process. This method avoids the influence of environmental factors such as temperature, humidity, and atmospheric pressure on the accuracy of ground microwave interference detection due to differences in seasons and time, and improves the detection accuracy of bridge dynamic deflection.
进一步地，所述步骤S2包括：Further, the step S2 includes:
按照公式计算本次检测时的所述大气折射率；according to the formula Calculate the atmospheric refractive index during this detection;
其中，n表示所述大气折射率，t表示所述大气干温，pd表示所述大气干空气分压力，pw表示所述大气水蒸气分压力。Wherein, n represents the refractive index of the atmosphere, t represents the dry temperature of the atmosphere, p d represents the partial pressure of the dry air in the atmosphere, and p w represents the partial pressure of the water vapor in the atmosphere.
本实施例综合考虑了大气干温、大气水蒸气分压力和大气干空气分压力对大气折射率的影响。In this embodiment, the effects of atmospheric dry temperature, atmospheric water vapor partial pressure, and atmospheric dry air partial pressure on the atmospheric refractive index are comprehensively considered.
进一步地，所述步骤S3包括：Further, the step S3 includes:
获取所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离，以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离；Obtain the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the center point of the radar of the microwave interference detection system obtained by at least one detection to the point to be detected on the bridge The radial distance between;
按照公式计算所述待检测点在垂直所述桥面下表面的方向上，偏离平行于所述桥面下表面的参考平面的距离，作为本次检测时的所述桥梁的动挠度；according to the formula Calculating the distance of the point to be detected from a reference plane parallel to the lower surface of the bridge deck in a direction perpendicular to the lower surface of the bridge deck, as the dynamic deflection of the bridge during this detection;
其中，di表示本次检测时的所述桥梁的动挠度，Ri表示第i次检测得到的径向距离，Ri-1表示第i-1次检测得到的径向距离，n表示所述大气折射率，h表示所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离。Among them, d i represents the dynamic deflection of the bridge during this detection, R i represents the radial distance obtained from the ith detection, R i-1 represents the radial distance obtained from the i-1 detection, and n represents the The atmospheric refractive index, h represents the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located.
需要说明的是，参考平面是用于表征待检测点偏移程度的平面，可以是如图2中所示的位于桥梁的路面所在平面202和桥梁下表面201中间，且距二者距离相等的位置，也可以是与路面所在平面202或者桥梁下表面201平行的其它平面，只要能够作为参考表征待检测点204的偏移距离即可。待检测点204位于桥梁上处于桥梁的路面所在平面202和桥梁下表面201之间的任意位置，例如，如图2所示，待检测点204位于参考平面203内。It should be noted that the reference plane is a plane used to characterize the offset degree of the point to be detected, which can be located between the plane 202 of the road surface of the bridge and the lower surface 201 of the bridge as shown in Figure 2, and the distance from the two is equal. The position may also be other planes parallel to the plane 202 where the road surface is located or the lower surface 201 of the bridge, as long as it can be used as a reference to represent the offset distance of the point 204 to be detected. The point 204 to be detected is located at any position on the bridge between the plane 202 of the road surface of the bridge and the lower surface 201 of the bridge. For example, as shown in FIG. 2 , the point 204 to be detected is located in the reference plane 203 .
进一步地，所述桥梁下表面平行于所述桥梁上的路面所在的平面。Further, the lower surface of the bridge is parallel to the plane where the road surface on the bridge is located.
进一步地，所述参考平面平行于所述桥梁下表面，且与所述桥梁下表面的之间的距离等于其与所述路面所在平面之间的距离；Further, the reference plane is parallel to the lower surface of the bridge, and the distance from the lower surface of the bridge is equal to the distance from the plane where the road surface is located;
所述待检测点位于所述参考平面内。The points to be detected are located in the reference plane.
参见图2，桥梁上的路面所在的平面为202，桥梁下表面指的是和路面所在的平面202平行的平面201，通常桥梁下表面201过桥柱或者桥台的上表面。参考平面203平行于桥梁下表面201，且与桥梁下表面201之间的距离等于其与路面所在平面202之间的距离。待检测测点204位于参考平面203内。Referring to FIG. 2 , the plane of the road on the bridge is 202 , and the lower surface of the bridge refers to a plane 201 parallel to the plane 202 of the road. Usually, the lower surface of the bridge 201 passes through the upper surface of the bridge column or abutment. The reference plane 203 is parallel to the lower surface of the bridge 201 , and the distance from the lower surface 201 of the bridge is equal to the distance from the plane 202 where the road surface is located. The measuring point 204 to be detected is located in the reference plane 203 .
本发明所述的一种用于地面微波干涉测量长周期铁路桥梁动挠度监测的大气参数改正方法还具有以下有益效果：简化的最佳加权平均系数的大气参数改正经验模型具有±1×10-7的精度，远远满足地面微波干涉测量桥梁动挠度监测大气参数改正的精度要求。本发明简化的最佳加权平均系数的大气参数改正经验模型(以上实施例中采用大气干温、大气水蒸气分压力和大气干空气分压力计算大气折射率的过程)，仅考虑影响大气折射率的三个重要因素，降低了大气数据采集时的难度，在保证测量精度的前提下，大大提高了铁路桥梁动挠度监测的效率。综合考虑大气折射率和仪器布设参数的影响，通过构建的铁路桥梁动挠度改正模型，可以大大消除地面微波干涉测量在不同季节和不同时间的大气参数和仪器布设参数(以上实施例中的几何特征参数)的影响，提高动挠度监测的精度，为铁路桥梁的健康状态和安全性分析和评估提供准确的数据支持。An atmospheric parameter correction method for ground microwave interferometry long-period railway bridge dynamic deflection monitoring also has the following beneficial effects: the simplified empirical model of atmospheric parameter correction with the best weighted average coefficient has ±1×10 - 7 , which far meets the accuracy requirements of ground microwave interferometry bridge dynamic deflection monitoring and atmospheric parameter correction. The atmospheric parameter correction empirical model of the optimal weighted average coefficient of the present invention (in the above embodiment adopts atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure to calculate the process of atmospheric refractive index), only considers influence atmospheric refractive index The three important factors reduce the difficulty of atmospheric data collection, and greatly improve the efficiency of railway bridge dynamic deflection monitoring under the premise of ensuring measurement accuracy. Comprehensively considering the influence of atmospheric refractivity and instrument layout parameters, the railway bridge dynamic deflection correction model constructed can greatly eliminate the atmospheric parameters and instrument layout parameters of ground microwave interferometry in different seasons and different times (geometric features in the above examples parameters), improve the accuracy of dynamic deflection monitoring, and provide accurate data support for the health status and safety analysis and evaluation of railway bridges.
图3是本实施例提供的基于微波干涉的桥梁动挠度检测的装置300的结构框图，参见图3，该基于微波干涉的桥梁动挠度检测的装置300包括获取模块301、计算模块302和处理模块303；Fig. 3 is a structural block diagram of a device 300 for detecting bridge dynamic deflection based on microwave interference provided in this embodiment. Referring to Fig. 3, the device 300 for detecting bridge dynamic deflection based on microwave interference includes an acquisition module 301, a calculation module 302 and a processing module 303;
获取模块301，用于获取干涉检测系统对待检测的桥梁检测过程中的几何特征参数，以及本次检测时的大气干温、大气水蒸气分压力和大气干空气分压力；The obtaining module 301 is used to obtain the geometric characteristic parameters of the bridge to be detected by the interference detection system during the detection process, as well as the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure during this detection;
计算模块302，用于根据所述大气干温、大气水蒸气分压力和大气干空气分压力计算本次检测时的大气折射率；Calculation module 302, for calculating the atmospheric refractive index during this detection according to the atmospheric dry temperature, atmospheric water vapor partial pressure and atmospheric dry air partial pressure;
处理模块303，用于根据所述大气折射率和所述几何特征参数，采用桥梁动挠度改正模型计算本次检测的所述桥梁的动挠度；The processing module 303 is used to calculate the dynamic deflection of the bridge detected this time by using a bridge dynamic deflection correction model according to the atmospheric refractive index and the geometric characteristic parameters;
其中，所述几何特征参数包括所述微波干涉检测系统的雷达的中心点到所述桥梁下表面所在平面的距离、以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离。Wherein, the geometric characteristic parameters include the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained at least once to the The radial distance between the points to be detected on the bridge.
本实施例提供的基于微波干涉的桥梁动挠度检测的装置300适用于以上实施例中所述的基于微波干涉的桥梁动挠度检测的方法，在此不再赘述。、The device 300 for detecting bridge dynamic deflection based on microwave interference provided in this embodiment is applicable to the method for detecting bridge dynamic deflection based on microwave interference described in the above embodiments, and will not be repeated here. ,
本实施例提供的基于微波干涉的桥梁动挠度检测的装置300中，考虑到微波在大气传播过程中会受到温度、湿度、大气压力等环境因素的影响，获取模块301大气干温、大气水蒸气分压力和大气干空气分压力分别进行检测，计算模块302由此确定大气折射率。处理模块303根据由此确定的大气折射率，以及检测过程中微波干涉仪和桥梁之间的几何位置关系确定的几何特征参数，计算出桥梁的动挠度。这种方法避免了由于季节和时间的差异，温度、湿度、大气压力等环境因素对地面微波干涉检测精度的影响，提高了桥梁动挠度的检测精度。In the device 300 for detecting bridge dynamic deflection based on microwave interference provided in this embodiment, considering that microwaves will be affected by environmental factors such as temperature, humidity, and atmospheric pressure during the propagation of microwaves in the atmosphere, the acquisition module 301 of the atmospheric dry temperature, atmospheric water vapor The partial pressure and the atmospheric dry air partial pressure are detected respectively, and the calculation module 302 determines the atmospheric refractive index accordingly. The processing module 303 calculates the dynamic deflection of the bridge according to the determined atmospheric refractive index and the geometric characteristic parameters determined by the geometric positional relationship between the microwave interferometer and the bridge during the detection process. This method avoids the influence of environmental factors such as temperature, humidity, and atmospheric pressure on the accuracy of ground microwave interference detection due to differences in seasons and time, and improves the detection accuracy of bridge dynamic deflection.
进一步地，所述计算模块用于按照公式计算本次检测时的所述大气折射率；Further, the calculation module is used according to the formula Calculate the atmospheric refractive index during this detection;
其中，n表示所述大气折射率，t表示所述大气干温，pd表示所述大气干空气分压力，pw表示所述大气水蒸气分压力。Wherein, n represents the refractive index of the atmosphere, t represents the dry temperature of the atmosphere, p d represents the partial pressure of the dry air in the atmosphere, and p w represents the partial pressure of the water vapor in the atmosphere.
进一步地，所述处理模块包括：Further, the processing module includes:
获取单元，用于获取所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离，以及至少一次检测得到的所述微波干涉检测系统的雷达的中心点到所述桥梁上的待检测点之间的径向距离；An acquisition unit, configured to acquire the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located, and the distance from the center point of the radar of the microwave interference detection system obtained by at least one detection to the bridge The radial distance between the points to be detected on ;
计算单元，用于按照公式计算所述待检测点在垂直所述桥面下表面的方向上，偏离平行于所述桥面下表面的参考平面的距离，作为本次检测时的所述桥梁的动挠度；Calculation unit, used to follow the formula Calculating the distance of the point to be detected from a reference plane parallel to the lower surface of the bridge deck in a direction perpendicular to the lower surface of the bridge deck, as the dynamic deflection of the bridge during this detection;
其中，di表示本次检测时的所述桥梁的动挠度，Ri表示第i次检测得到的径向距离，Ri-1表示第i-1次检测得到的径向距离，n表示所述大气折射率，h表示所述微波干涉检测系统的雷达的中心点到所述桥梁的下表面所在平面的距离。Among them, d i represents the dynamic deflection of the bridge during this detection, R i represents the radial distance obtained from the ith detection, R i-1 represents the radial distance obtained from the i-1 detection, and n represents the The atmospheric refractive index, h represents the distance from the center point of the radar of the microwave interference detection system to the plane where the lower surface of the bridge is located.
进一步地，所述桥梁下表面平行于所述桥梁上的路面所在的平面。Further, the lower surface of the bridge is parallel to the plane where the road surface on the bridge is located.
进一步地，所述参考平面平行于所述桥梁下表面，且与所述桥梁下表面的之间的距离等于其与所述路面所在平面之间的距离；Further, the reference plane is parallel to the lower surface of the bridge, and the distance from the lower surface of the bridge is equal to the distance from the plane where the road surface is located;
所述待检测点位于所述参考平面内。The points to be detected are located in the reference plane.
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.
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| CN107271095A (en) * | 2017-07-24 | 2017-10-20 | 湖南镭氪信息科技有限公司 | A kind of Suo Li remote sensing survey methods based on microwave interference |
| CN107687924A (en) * | 2017-08-28 | 2018-02-13 | 广州大学 | The safe early warning method and system of a kind of bridge |
| CN107687924B (en) * | 2017-08-28 | 2019-05-03 | 广州大学 | A bridge safety early warning method and system |
| CN113701968A (en) * | 2021-07-12 | 2021-11-26 | 北京建筑大学 | Bridge dynamic deflection monitoring system |
| CN113701968B (en) * | 2021-07-12 | 2023-10-13 | 北京建筑大学 | Bridge dynamic deflection monitoring system |
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