大型工程结构沉降位移监测方法及监测预警系统研究

Deformation measurement for structures and materials is one of the basic tasks in experimental mechanics. The subsidence deformation measurement, especially long time surveillance of large structures such as tunnels, roadbeds, dams and high slide slopes, is a problem that needs solved imperiously nowadays in the fields of engineering applications and academic discipline development. Existing subsidence measuring methods such as water level and theodolite, have the disadvantages of long work time, low efficiency, large workloads, furthermore they cannot meet the demand of long time and real-time surveillance. Applications of GPS have certain limitation for the low accuracy in the vertical direction..In this plan, an innovative concept of “displacement-relay videometrics” is proposed to establish a kind of repalcable and high-accuracate measurement method and analysis computing system for structure subsidence in order to meet the demand of long-term surveillance of subsidences of large engineering constructions. With high-accurate digital image measurement techniques, this method invents two constrains between multi-heads cameras and cooperative markers, formulates the displacement-relay measurement model, and finally calculats the subsidence of each marker and the pitch angle, the roll angle and the subsidence of each multi-heads cameras. The method can not only monitor the relative subsidence between each marker, but also monitor the absolute subsidence of the structure by means of unmovable reference points. We have applied to be granted in the international patent of the displacement-relay videometric method, whose implementation will promote the progress of the videometric technique and expand its application fields.

结构和材料的变形测量是实验力学的一项基本任务，而对于大型建筑设施（如隧道、路基、大坝、高边坡等大型结构）的变形测量,特别是长期监测，更是工程应用和学科发展中迫切需要解决的问题。现有的测量方法，如水准仪、经纬仪、全站仪等不仅工作量大、效率低，而且难以满足长期监测的需要。GPS也因垂直精度低等因素，其应用还存在一定局限性。.本项目将首次提出“位移传递摄像测量”的概念和方法，旨在建立一种可以更换的高精度结构沉降测量方法和分析计算系统，以满足大型建筑设施沉降位移长期监测的需要。该方法将采用高精度数字图像测量技术，建立多头像机站和共有标志物间的两类约束，运用位移传递测量数学模型，计算各标志物的沉降量和各像机站的倾斜角、旋转角及沉降量；不仅可以长期监测各标志物间的相对沉降，借助不动参考点，还可以直接监测结构的绝对沉降。本方法已申请国际发明专利，其实施将进一步推动摄像测量技术的发展、拓展其工程应用领域

本项目在位移传递像机链摄像测量、多种新型串联相机网络的理论方面取得了创新性的突出研究成果，对大型工程结构沉降位移监测技术的发展和工程应用具有重要意义。主要表现在以下几个方面：1. 提出了多种新型串联像机网络，包括单头串联像机链，闭环像机串联网络和串并联像机网络等。2. 优化了双头像机路基沉降监测模型解算方法，提出了多种精确标定多头像机关系的方法，研究了标识点精确提取算法，提高了位姿估计精度。3. 研制开发了沉降位移监测系统，该系统基于无线网络，利用GPS授时实现了同步控制及图像传输，系统具有图像数据的实时计算和分析功能。4. 将所发明的沉降位移监测方法及监测系统首次应用于南京长江大桥火车通过时桥面挠曲变形测量，以及隧道冻土顶管施工过程中机头位置和方向的自动测量，取得了很好的应用成果。