声纳技术在排水方涵淤泥厚度检测中的应用研究

Application of Sonar Technology in the Measurement of Siltation Thickness of Drainage Culvert

涵底淤积问题是影响排水方涵过流、排放能力的主要因素,定期开展方涵淤积情况检测,进行有效的清淤疏通工作,是提升方涵通水能力、防止城市内涝、维护城市环境的重要举措。本文介绍了一种方涵淤泥厚度的测量和计算方法,并就实践环节中相应的的注意事项和经验步骤进行了说明。首先对影响检测和计算结果的主要因素如声纳探头姿态、测试水位、不规则截面等进行了探讨,然后对方涵声纳成像数据处理过程中界面识别、姿态(转角及倾角)校正、坡度角校正、等效淤泥厚度计算等诸多关键性问题的解决方法进行了研究分析。结果表明,方涵管道声纳淤泥检测过程中,数据采集时应同步测量水面到涵顶的距离,数据处理时若量取淤积深度,应提前换算方涵顶底边界位置;数据处理时,对淤泥的镜像界面、水面、方涵顶板应进行有效的信号甄别;探头的姿态(包括左右转角、前后倾角、圆周转角),对测量结果影响较大,需要进行有效的角度校正;方涵顶底板和水面坡度角非完全一致,当测段跨度较大时,应进行坡度角校正;当淤泥顶界面不齐整时,不能随意量取任意点淤泥厚度,可根据淤泥界面面积计算等效淤积厚度。本文成果是工程实践的经验总结,是对管道声纳技术的应用推广,所提供的测量、校正、识别和计算方法对非圆形管道内淤泥厚度的声纳检测具有实际的参考价值。

Culvert bottom sedimentation is a major factor affecting the overflow and discharge capacity of the drainage culvert.This paper introduces a method of measuring and calculating the thickness of culvert silt,and explains the corresponding precautions and empirical steps in practice.The main factors affecting the detection and calculation results,such as sonar probe attitude,irregularity sedimentation section and test water level are discussed.The solutions to many key problems such as interface recognition,attitude(angle and inclination) correction,slope angle correction and equivalent deposition thickness calculation in the process of sonar imaging data processing are found.The results indicate that,when conducting sonar silt detection for square culvert pipelines,the distance from the water surface to the top of the culvert should be synchronously measured and the depth of sedimentation should be converted in advance to the boundary position of the top and bottom of the square culvert during data collection.Effective signal screening should be carried out on the mirror interface,water surface,and top slab of the square culvert of the silt during data processing.Secondly,the attitude of the probe(including left and right angles,front and rear angles,and circumferential angles) has a significant impact on the measurement results and requires effective angle correction.Thirdly,the slope angle between the top and bottom plates of the square culvert and the water surface is not completely consistent.When the span of the measurement section is large,slope angle correction should be carried out.Fourthly,When the interface of the silt top is not neat,the thickness of the silt at any point cannot be measured arbitrarily.The equivalent sediment thickness can be calculated based on the area of the silt interface.The results of this paper are the summary of engineering practice and the application promotion of pipeline sonar technology.The measurement,correction,identification and calculation methods provided in this paper have practically reference value for the sonar detection of silt thickness in non-circular pipelines.