Simulating the impact of highway construction to landslides with creep deformation using DDA: a case study of Qinglong landslide in Guizhou Province, China

The present study numerically simulates the kinematic behavior of Qinglong landslide before the construction of National Highway 60 in Guizhou and the interaction between the landslide and anti-slide piles after construction using discontinuous deformation analysis (DDA). Due to the excessive workload in simulating a creeping landslide with a slower deformation, the original DDA method which is usually simulated in seconds may not apply to creeping landslide in the present study. Therefore, DDA is improved to apply to landslides with a creep deformation by optimizing the time-related parameters and improving the dynamic simulation analysis. Previous studies predicted the behavior of landslides and the anti-sliding performance of the anti-slide facility using the field investigation and real-time monitoring data which is more accurate but needs substantial costs. To consider the characteristics of landslides, the dynamic simulation of the landslide formation and prevention involves three issues, namely, (i) the movement of the landslide, (ii) the anti-sliding performance of anti-slide piles, and (iii) the stress and strain of the piles, which can be analyzed using DDA. The simulation results coincide well with the preliminarily observed failure modes, and it indicates that the improved DDA can intuitively reproduce the creep deformation process of landslides and the anti-sliding performance of piles. Meanwhile, the stress analysis in DDA can provide a reference for the safety design of anti-slide piles and highway excavation in highway engineering.