Abstract:Rock fractures exhibit complex geometric characteristics such as intricate shapes and blurred boundaries during natural formation, and their images are often severely affected by background factors such as mineral texture and uneven lighting. In response to the problem of feature information loss and insufficient fitting reliability that U-Net and other models are prone to when processing such complex images, this paper proposes a rock fracture detection method that integrates improved U-Net and dual attention mechanism. By constructing a compressed pyramid structure to perform multi-scale convolution on the input image and combining spatial and channel dual attention mechanisms, the response weight of the crack area is strengthened, the interference of non crack backgrounds is suppressed, and the problem of feature loss is overcome. Further embedding the dual attention module into the encoder decoder framework of U-Net, using Dice and Focal joint loss functions and L2 regularization constraint model training to enhance the recognition ability of small and fuzzy cracks, and implementing pixel level crack mapping through scale scaling. The experimental results show that the detection error of this method for crack length is basically stable within 1.5mm, and the detection error for the overall crack distribution spacing is less than 10.0mm.