How to detect the engineering structure,
Let me introduce you. The main contents of overall structure monitoring include settlement observation, displacement observation, deflection observation, crack observation and vibration observation. The observation content of each type of building should be comprehensively determined according to the specific conditions and actual requirements of the building. Health monitoring methods are closely related to the development of measuring instruments. At present, GPS positioning technology has been applied to regional deformation observation and large-scale engineering deformation monitoring, which has the advantages of immediate, continuous and automatic monitoring, and can even be combined with remote data transmission to realize intelligent monitoring and decision-making. The accuracy of monitoring depends on the scientificity of monitoring scheme, the rationality of monitoring point layout and the accuracy of measuring instruments.
Structural monitoring methods can be divided into four categories: (1) spatial domain method, (2) modal domain method, (3) time domain method and (4) frequency domain method. Among them, the spatial domain method detects and determines the damage location according to the changes of mass, damping and stiffness matrix, while the modal domain method detects the damage according to the changes of natural frequency, modal damping ratio and modal shape. In the time domain method.
The system parameters are directly determined by the data sampled in a certain period of time, which has high accuracy but takes a long time. Frequency domain method is used to determine natural frequency, damping ratio, vibration mode and other modal parameters, and spectrum analysis and frequency response function are widely used. Each of the above methods has its advantages and disadvantages. If the frequency domain method and the modal domain method use the converted data, there will be errors and noises in the data conversion. In the space domain method, there are still some problems in the modeling and correction of mass and stiffness matrix, so it is difficult to be accurate. Combining two or three methods to detect and evaluate structural damage has a strong development trend. For example, combining the data of static load test and modal test for damage diagnosis can overcome the shortcomings of various methods and check each other. Adapted to the complexity of damage detection. Structural performance testing is an important part of reliability appraisal, which generally includes the mechanical properties of structural materials, structural measures, structural member size, location and diameter of steel bars, cracking and deformation of structures and members.
After reading the above article, I hope this article can help you understand the engineering structure detection.