A method for dynamic observation of flood discharge surface with prism-free total station

Abstract

The invention relates to a method for dynamically observing flood discharge surface lines with a prism-free total station, belonging to the field of water conservancy engineering measurement. The present invention first finds an easy observation point near the top of the water surface line to be observed as the working base point, and uses the total station to measure the elevation of the working base point and the distance between the station; Measure the point, and measure the horizontal angle and vertical angle between the point to be measured and the working base point in time; then use the triangular relationship between the point to be measured and the working base point to calculate the height difference between the point to be measured and the working base point, and obtain the water surface The elevation of the line. This method can overcome the problem of the weak return light signal of the total station, and because the point to be measured is located in the wave area, the waves fluctuate quickly and the exposure time is extremely short, so it is impossible to directly measure the elevation of the point to be measured, and realize the measurement of the wave in the area affected by the wave. The real-time and fast measurement of points provides a new method for dynamic and fast observation of dynamic water surface lines.

Description

technical field [0001] The invention relates to a method for dynamically observing flood discharge surface lines with a prism-free total station, belonging to the field of water conservancy engineering measurement. Background technique [0002] When the dam discharges floods, due to the large flow rate and high velocity of the discharged water, it will cause huge erosion, cavitation, and vibration to the downstream stilling pool, which will seriously test the safety of the stilling pool. Therefore, there is an urgent need in engineering to quickly and accurately measure the water surface line downstream of the dam during flood discharge to meet the hydraulic characteristics and stability and safety analysis of the stilling basin, determine a reasonable flood discharge plan, and reduce the impact of the discharged water on the safety of the stilling basin. influences. [0003] In the current water surface line measurement method, the traditional water level measurement needs...

AI Technical Summary

Problems solved by technology

Li Yi and others proposed the technology of detecting the water surface line through image recognition technology, but this method also needs to set up a scale at the point to be measured; in addition, if the scale is stained during the measurement process, it will have a greater impact on the measurement results; Bao Jiang By collecting video images, and then detecting the water level line through Haar features, but this method requires the water surface to be measured to be stable when collecting video images, and when the stilling pool is flooded, the water flow is relatively turbulent, the water surface fluctuates greatly, and the water surface is very high. It is difficult to keep calm, and at the same time, this method is prone to false detection when the sunlight is relatively strong, and the concrete on both sides of the stilling pool reflects the sunlight strongly, so this method is difficult to detect when the stilling pool is flooded. Effective observation of the water surface line; Li Dongfeng et al. measure the elevation of the water surface line through the tide gauge and GPS technology, but require the tide gauge to be stable, and at the same time require the GPS rover to be installed on the survey ship, and when the stilling pool discharges the flood, the water flow is turbulent and the waves roll Whether it is a tide gauge or a GPS survey ship, it is difficult to maintain stability during flood discharge, so it cannot be used for dynamic measurement of the stilling pool water surface; Three-dimensional reconstruction of the water surface, but this method cannot directly measure the elevation of the water surface line in real time

Although these methods have been improved, they still cannot meet the requirements for fast and efficient observation of the flood discharge surface.

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