Vehicle detection is essential for road traffic surveillance and active safety management. Deep learning methods have recently shown robust feature extraction capabilities and achieved improved detection results. However, vehicle detection models often perform poorly under abnormal lighting conditions, especially in highway tunnels. We proposed an adaptive vehicle detection model that accounts for varying luminance intensities to address this issue. The model categorizes the image data into abnormal and normal luminance scenarios. We employ an improved CycleGAN with edge loss as the adaptive luminance adjustment module for abnormal luminance scenarios. This module adjusts the brightness of the images to a normal level through a generative network. Finally, YOLOv7 is utilized for vehicle detection. The experimental results demonstrate that our adaptive vehicle detection model effectively detects vehicles under abnormal luminance scenarios in highway tunnels. The improved CycleGAN can effectively mitigate edge generation distortion. Under abnormal luminance scenarios, our model achieved a 16.3% improvement in precision, a 1.7% improvement in recall, and a 9.8% improvement in mAP_0.5 compared to the original YOLOv7. Additionally, our adaptive luminance adjustment module is transferable and can enhance the detection accuracy of other vehicle detection models.

Expansive soils undergo significant volumetric changes during wetting and drying, often leading to structural deterioration and engineering difficulties. Alkali-activated binders have been widely utilized to improve the mechanical performance and durability of such soils. This study examines the performance of γ-aminopropyltriethoxysilane (KH-550)-modified alkali-activated binder-stabilized expansive soils (AABS). As a result, the addition of KH-550 extended the setting times by up to 89% and enhanced fluidity by 6–27%, thereby improving the workability of AABS. The additive delayed early hydration while accelerating later-stage gel formation via hydrolysis and Si–O–Si bond generation, promoting the development of C-(A)-S-H. Microstructural observations indicated a refinement of pores and a reduction in capillary porosity, yielding a denser and more homogeneous matrix. Autogenous shrinkage was reduced by as much as 32.5%, and the unconfined compressive strength of 7 d AABS increased by 58.1% at an optimal KH-550 dosage of 1.0 wt.%, with mechanical performance remaining stable under wet–dry cycling. Overall, these results suggest that KH-550 serves as an effective organic–inorganic bridging agent, offering a viable strategy for the stabilization of expansive soils.

Expansive soil is prone to significant swelling and shrinkage deformation with changes in moisture conditions, posing serious safety hazards to engineering construction. This study focuses on alkali-activated self-compacting fluid-solidified soil (ASFS) and systematically explores the regulatory effect of expansive soil with different dosages (0–100%) on its properties. This study analyzes the influence of expansive soil on the setting time, hydration characteristics, autogenous shrinkage, and compressive strength of ASFS while verifying the feasibility of this method for solidifying expansive soil through microstructural analysis. The results show that, with the increase in content of expansive soil, the initial and final setting times of ASFS were prolonged by 0.08–1.58 times and 0.08–1.29 times, respectively. Although expansive soil inhibited the hydration of ASFS, it could compensate for autogenous shrinkage through the expansion effect of clay minerals, reducing the autogenous shrinkage by 13.4–51.2%. Furthermore, the optimal dosage of expansive soil in ASFS is 60%. Compared with the control group, the 7d compressive strength of ASFS increases by 52.4%, the strength after 3d water immersion rises by 62.6%, and the strength after eight wet–dry cycles still remains 10% higher. This optimal dosage achieves the best balance between mechanical properties, water stability, and shrinkage resistance of ASFS, providing a reliable technical reference for the efficient utilization of expansive soil in engineering.