Bridge small target crack detection based on improved YOLOv8

Jinpei LI, Xiaolin MENG, Liangliang HU, Yan BAO, Shiyu ZHAO

Journal of Tsinghua University(Science and Technology) ›› 2025, Vol. 65 ›› Issue (7) : 1260-1271.

PDF(11644 KB)
PDF(11644 KB)
Journal of Tsinghua University(Science and Technology) ›› 2025, Vol. 65 ›› Issue (7) : 1260-1271. DOI: 10.16511/j.cnki.qhdxxb.2025.26.023
Intelligent Construction

Bridge small target crack detection based on improved YOLOv8

Author information +
History +

Abstract

Objective: The structural integrity of bridges is a critical concern as infrastructure ages, necessitating the development of reliable methods for detecting potential failures. Among these, the identification of small target cracks is particularly important, as these cracks often grow undetected until they result in severe damage. Traditional inspection methods, such as manual visual inspections, are hindered by their labor-intensive nature and susceptibility to human error, often resulting in the oversight of small but significant defects. Recent advancements in computer vision and deep learning technologies offer new opportunities to improve the accuracy and efficiency of bridge inspections. This study introduces an innovative approach for detecting small target cracks in bridge structures by employing an enhanced version of the You Only Look Once (YOLOv8) object detection model, a widely recognized algorithm known for its rapid processing capabilities and high detection accuracy. The enhanced YOLOv8 model is tailored to detect small-scale cracks on bridge surfaces that may not be easily identifiable by traditional inspection methods or earlier versions of computer vision models. Methods: The proposed algorithm modifies the standard YOLOv8 model to address the specific challenges associated with detecting small cracks on bridge surfaces. A key modification is the integration of efficient vision transformer (EfficientViT) into the backbone of the YOLOv8 model. EfficientViT is an advanced transformer-based architecture that reduces redundant parameters and optimizes the extraction of local features from high-resolution images, enabling more precise detection of subtle crack features. This enhancement is crucial, as small cracks often exhibit low contrast against their background and may be easily overlooked by less sophisticated models. In addition to EfficientViT, the proposed algorithm also incorporates large selective kernel network (LSKNet) within the C2f module of YOLOv8. LSKNet employs a dynamic kernel selection mechanism that allows the model to adaptively adjust the size of the convolutional kernels based on the input features, making it highly suitable for detecting cracks of varying sizes, orientations, and morphological characteristics. This adaptability ensures that the model can detect small cracks, regardless of their form. Furthermore, the model uses bidirectional feature pyramid network (BiFPN) to merge feature maps at different scales. Traditional models struggle with detecting small targets due to the loss of critical information during downsampling operations. BiFPN mitigates this issue by preserving high-resolution feature maps across multiple layers, enhancing the model's ability to detect small cracks that would otherwise be missed. The combined effect of these modifications improves the accuracy of small target crack detection while maintaining computational efficiency. Results: The effectiveness of the proposed model was validated using a dataset of crack images from a specific bridge, captured by unmanned aerial vehicles (UAVs). UAVs provided detailed images from areas that were often difficult or dangerous to access using traditional inspection methods. The experimental results demonstrated that the enhanced YOLOv8 model significantly outperformed the original version in terms of key performance metrics. Specifically, the modified model achieved improvements of 3.7%, 3.5%, 3.5%, 3.9%, and 7.4% in terms of the detection precision, recall, F1 score, mAP50, and mAP50-95, respectively. These results indicated a substantial improvement in the model's ability to detect small cracks that often had low contrast and irregular shapes, which were typical characteristics of cracks on bridge surfaces. Furthermore, compared to conventional methods, the proposed model was able to detect cracks with higher precision and fewer false positives, making it a promising tool for improving the efficiency of bridge inspections. Conclusions: In conclusion, the improved YOLOv8 algorithm introduced in this study represents a significant advancement in the detection of small target cracks in bridge structures. The modifications made to the original YOLOv8 model, including the integration of EfficientViT, LSKNet, and BiFPN, result in a more accurate and computationally efficient model for crack detection. This approach offers a practical and scalable solution for the widespread application of bridge health monitoring, particularly in areas that are difficult to inspect using traditional methods. By leveraging advanced surface data processing techniques, this research contributes to the development of modern methods for assessing the health of bridge structures, ultimately helping to ensure the safety and longevity of infrastructure systems.

Key words

bridge structure health monitoring / unmanned aerial vehicle / small target crack detection / YOLOv8 / image processing

Cite this article

Download Citations
Jinpei LI , Xiaolin MENG , Liangliang HU , et al . Bridge small target crack detection based on improved YOLOv8[J]. Journal of Tsinghua University(Science and Technology). 2025, 65(7): 1260-1271 https://doi.org/10.16511/j.cnki.qhdxxb.2025.26.023

References

1
《中国公路学报》编辑部. 中国桥梁工程学术研究综述·2021[J]. 中国公路学报, 2021, 34 (2): 1- 97.
China Journal of Highway and Transport . Review on China's bridge engineering research: 2021[J]. China Journal of Highway and Transport, 2021, 34 (2): 1- 97.
2
交通运输部. 2023年交通运输行业发展统计公报[N]. 中国交通报, 2024-06-18(2).
Ministry of Transport. 2023 statistical bulletin on the development of the transport industry[N]. China Transportation News, 2024-06-18(2).
3
KUŠTER MARIĆ M , MANDIĆ IVANKOVIĆ A , SRBIĆ M , et al. Assessment of performance indicators of a large-span reinforced concrete arch bridge in a multi-hazard environment[J]. Buildings, 2022, 12 (7): 1046.
4
岳清瑞, 徐刚, 刘晓刚. 桥梁裂缝智能识别与监测方法研究[J]. 中国公路学报, 2024, 37 (2): 16- 28.
YUE Q R , XU G , LIU X G . Crack intelligent recognition and bridge monitoring methods[J]. China Journal of Highway and Transport, 2024, 37 (2): 16- 28.
5
刘宇飞, 冯楚乔, 陈伟乐, 等. 基于机器视觉法的桥梁表观病害检测研究综述[J]. 中国公路学报, 2024, 37 (2): 1- 15.
LIU Y F , FENG C Q , CHEN W L , et al. Review of bridge apparent defect inspection based on machine vision[J]. China Journal of Highway and Transport, 2024, 37 (2): 1- 15.
6
余加勇, 李锋, 薛现凯, 等. 基于无人机及Mask R-CNN的桥梁结构裂缝智能识别[J]. 中国公路学报, 2021, 34 (12): 80- 90.
YU J Y , LI F , XUE X K , et al. Intelligent identification of bridge structural cracks based on unmanned aerial vehicle and Mask R-CNN[J]. China Journal of Highway and Transport, 2021, 34 (12): 80- 90.
7
余加勇, 刘宝麟, 尹东, 等. 基于YOLOv5和U-Net3+的桥梁裂缝智能识别与测量[J]. 湖南大学学报(自然科学版), 2023, 50 (5): 65- 73.
YU J Y , LIU B L , YIN D , et al. Intelligent identification and measurement of bridge cracks based on YOLOv5 and U-Net3 +[J]. Journal of Hunan University (Natural Sciences), 2023, 50 (5): 65- 73.
8
SHI Y , CUI L M , QI Z Q , et al. Automatic road crack detection using random structured forests[J]. IEEE Transactions on Intelligent Transportation Systems, 2016, 17 (12): 3434- 3445.
9
REN S Q , HE K M , GIRSHICK R , et al. Faster R-CNN: Towards real-time object detection with region proposal networks[J]. IEEE Transactions on Pattern Analysis and Machine Intelligence, 2017, 39 (6): 1137- 1149.
10
REDMON J, DIVVALA S, GIRSHICK R, et al. You Only Look Once: unified, real-time object detection[C]//Proceedings of the 2016 IEEE Conference on Computer Vision and Pattern Recognition. Las Vegas, USA: IEEE, 2016.
11
YU Z W , SHEN Y G , SHEN C K . A real-time detection approach for bridge cracks based on YOLOv4-FPM[J]. Automation in Construction, 2021, 122, 103514.
12
KUMAR P , BATCHU S , SWAMY S N , et al. Real-time concrete damage detection using deep learning for high rise structures[J]. IEEE Access, 2021, 9, 112312- 112331.
13
YANG Z , LI L , LUO W T . PDNet: Improved YOLOv5 nondeformable disease detection network for asphalt pavement[J]. Computational Intelligence and Neuroscience, 2022, 2022, 5133543.
14
TENG S , LIU Z C , LI X D . Improved YOLOv3-based bridge surface defect detection by combining high- and low-resolution feature images[J]. Buildings, 2022, 12 (8): 1225.
15
WU Y , HAN Q B , JIN Q L , et al. LCA-YOLOv8-Seg: An improved lightweight YOLOv8-Seg for real-time pixel-level crack detection of dams and bridges[J]. Applied Sciences, 2023, 13 (19): 10583.
16
REIS D, KUPEC J, HONG J, et al. Real-time flying object detection with YOLOv8[Z/OL]. (2023-05-17)[2024-03-15]. https://arxiv.org/abs/2305.09972.
17
FENG C J, ZHONG Y J, GAO Y, et al. TOOD: Task-aligned one-stage object detection[C]//Proceedings of the 2021 IEEE/CVF International Conference on Computer Vision. Montreal, Canada: IEEE, 2021.
18
CAI H, LI J Y, HU M Y, et al. EfficientViT: Lightweight multi-scale attention for high-resolution dense prediction[C]//Proceedings of the 2023 IEEE/CVF International Conference on Computer Vision. Paris, France: IEEE, 2023.
19
Alexey D. An image is worth 16×16 words: Transformers for image recognition at scale[Z/OL]. (2020-10-22)[2024-03-15]. https://arxiv.org/abs/2010.11929.
20
LI Y X, HOU Q B, ZHENG Z H, et al. Large selective kernel network for remote sensing object detection[C]//Proceedings of the 2023 IEEE/CVF International Conference on Computer Vision. Paris, France: IEEE, 2023.
21
ZHANG H L , DU Q F , QI Q Y , et al. A recursive attention-enhanced bidirectional feature pyramid network for small object detection[J]. Multimedia Tools and Applications, 2023, 82 (9): 13999- 14018.
22
CHEN L W , YANG J J . A lightweight YOLOv5-based model with feature fusion and dilation convolution for image segmentation[J]. Mathematics, 2023, 11 (16): 3538.
23
PATIL S , DAVE G , URMODE S . A comparative analysis of YOLOv8 and YOLOv5 for nut thread classification-deep learning approach[J]. International Journal for Research in Applied Science & Engineering Technology, 2024, 12 (2): 176- 182.

RIGHTS & PERMISSIONS

All rights reserved. Unauthorized reproduction is prohibited.
PDF(11644 KB)

Accesses

Citation

Detail

Sections
Recommended

/