基于卷积神经网络的桥梁裂缝检测研究

为了实现桥梁裂缝自动化检测,将无人机技术与图像识别技术相结合,利用深度学习框架搭建卷积神经网络模型,识别无人机采集的桥梁外观图片,达到了精确检测桥梁裂缝的效果,具有一定实际应用价值。     

无人飞机在广西桥梁检测中的应用发展

针对目前传统的公路桥梁检测手段的局限性,创新性地引入无人机检测理念,将无人机技术、计算机技术、航空摄影技术、互联网技术结合起来,提出一种全新的公路桥梁检测思路,该方法可广泛应用于广西公路桥梁检测中,有效提高了广西公路桥梁检测效率、缩短检测周期、节省工程检测费用,并可向全区工程检测其他领域拓展。     

无人机在公路桥梁检测中的应用

随着我国桥梁建设体量及在役桥梁龄期的不断增长,桥梁管养已经成为1个重大研究课题。常规的桥梁检测手段,由于其自身的局限性,已经难以满足桥梁管养的要求。因而,在桥梁检测领域急需使用自动化作业设备来弥补现有检测方式的不足。其中,无人机因其小巧灵活的特点已经被成功应用于桥梁检测领域。文章基于吉林省某大桥和江西省某大桥的无人机检测应用实例,分别对无人机桥梁检测系统的组成、应用优势和检测关键技术进行了介绍,通过采用无人机对桥梁经常性检查部位进行检测,阐述了无人机检测的具体内容,为无人机桥梁检测提供参考经验。     

浅析3×20m连续梁桥检测技术

桥梁检测主要包括外观检测和荷载试验。桥梁外观技术状况主要依外观检查和无损检测数据进行评定;桥梁荷载试验分为静荷载和动荷载试验。本文针对连续梁检测技术,结合某3x20m钢筋混凝土连续箱梁工程,阐述了连续梁桥外观检查、荷载试验的主要程序,及等效荷载作用下桥梁结构的应力、挠度及动态效应。     

基于图像技术的无人机系统在桥梁检测的应用

论述如何将无人机技术和红外成像技术、高清成像技术结合,试探性的运用在桥梁检测领域,探讨基于图像处理技术的无人机系统在结构健康检测领域的实用性和局限性。     

浅谈人行桥的混凝土强度问题

人行桥经多年的运营出现了不同程度的破坏,桥梁混凝土的表面破坏更是严重,为正确反映该桥的使用性能及受力行为,对桥进行了外观检测和混凝土的强度检测,并对该桥的混凝土强度作出评价。     

单跨双曲拱桥检测及分析

通过对一座单跨双曲拱桥进行外观检测及静载试验,对该公路旧桥技术状况进行了评估,判断了桥梁的承载能力,以期为该类桥梁的维护使用和检测加固工作提供指导。     

无人机在沿海腐蚀环境桥梁病害巡检中的应用

无人机技术已逐步应用于桥梁的病害检测中,本文针对服役于沿海腐蚀环境中桥梁对混凝土耐久性较高的特点,特别是混凝土裂缝宽度限制、防腐涂料开裂等,采用无人机对上述病害进行了定量化检测的应用。特别是针对混凝土裂缝宽度量测,本文利用无人机进行了裂缝宽度量测尺的设置,实现了裂缝宽度的精确测量。研究表明,无人机检测技术相比传统方法可显著扩大巡检范围,同时便利性、安全性、经济性等方面也优势明显。     

基于BIM技术的桥梁拉索表面缺陷检测仿真

桥梁拉索表面缺陷检测是预防桥梁腐蚀、损伤、断裂、老化等病害的一个重要课题。为了解决当前人工检测方法存在检测精准度不高、查全率较低,获得的桥梁拉索表面缺陷图像拼接效果不佳,效率低下的问题,提出了基于BIM技术的桥梁拉索表面缺陷检测方法,该方法采用BIM技术实现了桥梁自动化三维建模,基于该模型,采用4个CCD摄像机组成的图像采集阵列获取桥梁拉索表面一周的图像,并设计了一个3×3窗口的快速中值滤波算法对该图像做预处理,同时采用灰度对比度增强方法有效减小了缺陷图像对光源光照强度的敏感性;在此基础上,采用高斯差分函数提取桥梁拉索表面缺陷特征点,计算每个特征点的梯度幅值和方向,生成特征描述符;采用加权平均融合法完成桥梁拉索表面缺陷图像完整拼接,实现缺陷检测。实验结果表明,所提方法能够实现桥梁拉索表面缺陷检测,提高了检测精准度和查全率,且得到的桥梁拉索表面缺陷图像拼接效果较好,拼接效率较高。     

基于BIM的无人机桥梁检测实施方案研究

近年来随着我国经济水平的不断提高,国家加大了对基础设施的投资建设力度。在桥梁工程建设方面,在役桥梁使用年限不断增长,桥梁结构及相应病害问题逐渐凸显,进而对桥梁的检测与维护工作提出了更高的要求。本文在分析了现阶段我国传统桥梁检测方法的诸多不足和局限后,提出了基于BIM的无人机桥梁检测实施方案,探讨了BIM技术与无人机这一辅助手段在桥梁检测方面的充分结合以及其应用可行性,为未来桥梁检测技术水平的提升提供参考依据。     

The development of a mobile manipulator imaging system for bridge crack inspection

A mobile manipulator imaging system is developed for the automation of bridge crack inspection. During bridge safety inspections, an eyesight inspection is made for preliminary evaluation and screening before a more precise inspection. The inspection for cracks is an important part of the preliminary evaluation. Currently, the inspectors must stand on the platform of a bridge inspection vehicle or a temporarily erected scaffolding to examine the underside of a bridge. However, such a procedure is risky. To help automate the bridge crack inspection process, we installed two CCD cameras and a four-axis manipulator system on a mobile vehicle. The parallel cameras are used to detect cracks. The manipulator system is equipped with binocular Charge Coupled Devices (CCD) for examining structures that may not be accessible to the eye. The system also reduces the danger of accidents to the human inspectors. The manipulator system consists of four arms. Balance weights are placed at the ends of Arms 2 and 4, respectively, to maintain the center of gravity during operation. Mechanically, Arms 2 and 4 can revolve smoothly. Experiments indicated that the system could be useful for bridge crack inspections.     

Use of gaming technology to bring bridge inspection to the office

Abstract

This paper proposes a novel method for bridge inspection that essentially digitises bridges using Light Detection and Ranging (LIDAR) so that they can be later inspected in a virtual reality (VR) environment. The work uses conventional terrestrial LIDAR together with affordable VR hardware and freely available software development kits originally intended for authoring computer games. The resulting VR app is evaluated for a case study involving a typical masonry bridge, comparing the proposed technique with traditional inspection methods. The new approach promises to be highly effective in terms of interpretation of results, accessibility to critical areas and safety of inspectors. The work represents an important step towards the creation of digital twins of important assets in the built environment. Recent bridge collapse incidents have affected local economies, traffic congestion, and in some extreme cases led to a loss of life. The work is timely as law making agencies are paying greater attention to structural rehabilitation. This paper will be of particular interest to bridge engineers, construction professionals and law makers and could lead to future revisions of bridge inspection processes and standards.     

Improving the reliability of a Bridge Management System (BMS) using an ANN-based Backward Prediction Model (BPM)

The slow adoption of Bridge Management Systems (BMSs) and its impractical future prediction of the condition rating of bridges are attributed to the inconsistency between BMS inputs and bridge agencies' existing data for a BMS in terms of compatibility and the enormous number of bridge datasets that include historical structural information. Among these, historical bridge element condition ratings are some of the key pieces of information required for bridge asset prioritisation but in most cases only limited data is available.

This study addresses the abovementioned difficulties faced by bridge management agencies by using limited historical bridge inspection records to model time-series element-level data. This paper presents an Artificial Neural Network (ANN) based prediction model, called the Backward Prediction Model (BPM), for generating historical bridge condition ratings using limited bridge inspection records. The BPM employs historical non-bridge datasets such as traffic volumes, populations and climates, to establish correlations with existing bridge condition ratings from very limited bridge inspection records. The resulting model predicts the missing historical condition ratings of individual bridge elements. The outcome of this study can contribute to reducing the uncertainty in predicting future bridge condition ratings and so improve the reliability of various BMS analysis outcomes.     

结构表面裂缝数字图像法识别研究综述与前景展望

裂缝反映结构受力状态与安全性、耐久性,是结构现场安全性检测监测以及结构模型试验研究的重要指标之一.现有的人工裂缝识别技术难以满足工程现场与实验室需求,操作中存在测不准、高空多、效率低、记不全等缺点.相比之下,采用数字图像法进行结构表面裂缝识别,具有便捷、自动、定量、准确等优势.文章对结构表面裂缝数字图像法识别研究进行系...     

基于传统与创新理念的法国城市桥梁

本文系统地介绍了笔者前些年考察法国期间,对巴黎、里昂和尼斯等城市的城市桥梁建设的总体印象和分类考察情况。文中重点介绍了法国在城市桥梁建设上体现传统与创新的成功经验,为国内同行们提供有借鉴意义的资料和启示,以期促进我国城市桥梁建设的健康发展。     

Automatic multi-image stitching for concrete bridge inspection by combining point and line features

Most of the current techniques for concrete bridge inspection are based on human visual interpretation, which often is dangerous and time-consuming. To address this problem, we introduce in this paper a newly developed vehicle-based robot inspection system that can automatically capture thousands of bottom surface images with a group of high-resolution industrial cameras, which are then stitched into a single composite image. However, traditional image stitching methods generally fail with large drift due to the great number (more than 2000) and sparse texture of linearly distributed images in sequence. Therefore, a novel image stitching method was developed for our robot inspection system, which combines both the 2D image point features and the 3D line features to reduce the drift. First, the bottom surface images are arranged into different strips based on their acquisition order and rough poses, and images in a single strip are divided into several groups. Then, the proposed image stitching method is performed in a bottom-up way, as follows: 1) the images within a single group initially are aligned via their point and line features; 2) the groups within a single strip are then stitched together via a homographic refinement procedure; 3) the strips are aligned into a single composite image that completely covers the bottom surface of the bridge; and 4) after all the stitching procedure are complete, a multi-band blending algorithm is applied to generate the mosaicked panorama as seamlessly as possible. The experimental results on a set of representative images acquired from the bottom surfaces of a real bridge demonstrate the capabilities and the limitations of the proposed approach.     

台北捷運系統隧道檢測作業簡介

介绍目前台北捷運系統採用之DER結構檢查評估方法之應用情形,並針對結構安全評估與隧道影像掃描資料建立之作法加以說明。DER檢查方法目前已廣泛應用於橋梁結構檢查,台北捷運公司目前將其擴大應用至隧道結構例行檢查工作上,包括平時及定期之目視結構檢查作業,並建立專用之結構管理资訊系統,將結構之各項基本资料、執行檢测結果及維修紀錄等資訊加以管理應用。另外,針對隧道結構安全性之評估作業,則透過專業之工程顧問公司協助進行,針對隧道結構潛在性及隱藏性之瑕疵加以檢測評估,同時利用數位影像掃描技術,將隧道内之完整影像掃描儲存為數位檔案,作為影像紀錄及未來追蹤比對之依據。     

沥青面层施工时桥梁伸缩缝的临时处理

结合施工过程中的实际问题,从原材料及成品进场的检验工作和施工工艺等方面对沥青面层施工时桥梁伸缩缝的处理进行了探讨,以保证桥梁伸缩缝的安装质量和运营后的行车质量。     

尤溪县水东大桥多结构组合桥梁性能检测

尤溪县城关水东大桥是由三种体系的预应力混凝土结构组合而成的新建桥梁,为了解该桥的工作性能状态,交工前我们严格按规程标准对该桥外观和结构进行专项检测.通过特定车辆静止作用于桥梁的最不利荷载位置,以及脉动试验和行车动载试验测定该桥结构的静动力特性、动力效应和使用条件.设计不同的加载工况,检测桥梁最不利截面的变形和受力状态,...