Fine detection technology of rock mass structure based on borehole acousto-optic combined measurement

•Detection Equipment by acoustic scanning and optical image fusion.•A technology system of 3D imaging and feature parameter extraction.•A new method of rock mass structure fine detection. Aiming at the problem of rock mass structure fine detection, a solution idea of synchronous data acquisition based on acoustic scanning technology and borehole panoramic image technology is proposed. Based on the omni-directional acoustic pulse reflection sequence data and panoramic optical borehole image, the problem of difficult calculation of typical borehole structure scale and extended azimuth positioning is solved. A 3D modeling and data visualization optimization scheme of borehole rock mass structure based on full pulse acoustic scanning data and forward-looking borehole optical image is formed. By combining the acoustic scanning characteristics of section and the optical image characteristics of rock wall, the extraction technology of borehole rock mass structural characteristic parameters is formed. The 3D imaging and characteristic parameter extraction technology system of borehole rock mass structure is formed, which is applied to the actual borehole rock mass structure detection. The detection results are consistent with the actual characteristics.