In the construction of infrastructures such as the large-scale water conservancy, hydropower, energy and transportation, it is important to find out the bad geological characteristics in rock mass structure to ensure the smooth construction of the project. However, conventional geophysical prospecting methods are difficult to detect the fine characteristics of the borehole surrounding rock structure, such as the range and trend of the abnormal area. Therefore, a new method was proposed based on the laboratory rock sample defect detection method. The method based on directional acoustic scanning of detecting borehole surrounding rock structure was realized by combining directional acoustic probe, rotating parts and positioning device in order to be suitable for detecting borehole surrounding rock structure characteristics. Firstly, the annular scanning matrix was established according to the scanning detection data, and the data processing method for constructing the annular scanning map was put forward. Then, the mapping relationship between the acoustic data and the annular scanning matrix was constructed, and the corresponding acoustic processing data were matched according to the mapping relationship, thus forming the structural sectional map of the surrounding rock of the borehole. After superimposing the depth information, the structure of the surrounding rock of the borehole was realized. Finally, aiming at the difficulty of determining the parameters of rock sound velocity and defect location in the defect area of borehole surrounding rocks, two-dimensional scanning vectors of sound velocity and distance dimension were constructed by using the phase characteristics of different frequency acoustic wave transmission in rocks, and numerical analysis method was used to solve the acoustic velocity of rock and the location of abnormal area, thus realizing the structural characteristics of borehole surrounding rocks. Signature stereo rendering and parameter extraction were applied to practical engineering, and the feasibility and accuracy of the method were verified.
