Hydraulic behavior and stability of the Xincheng North Gate wall under extreme climatic conditions

The rammed earth wall of Xincheng North Gate is an important carrier of Ankang’s historical memory and cultural heritage. However, increasingly frequent extreme weather events may alter its hydraulic behavior and weaken its strength and stability. This study investigates the hydraulic response of the gate wall under extreme climatic conditions using site investigation, laboratory testing, and numerical simulation. The results show that continuous long-duration rainfall produces greater infiltration volume and depth than short-duration heavy rainfall, and causes wider variations in pore water pressure and volumetric moisture content. Repeated wetting-drying cycles further change the hydraulic state of the wall, reducing shear strength and overall stability. The influence of traffic loads under rainfall conditions is also evaluated. This study provides a numerical framework for assessing the hydraulic behavior and stability of rammed-earth heritage walls exposed to extreme weather.